Impeller for catheter pump

Information

  • Patent Grant
  • 11260213
  • Patent Number
    11,260,213
  • Date Filed
    Thursday, October 29, 2020
    4 years ago
  • Date Issued
    Tuesday, March 1, 2022
    2 years ago
Abstract
An impeller for a pump is disclosed herein. The impeller can include a hub having a fixed end and a free end. The impeller can also have a plurality of blades supported by the hub. Each blade can have a fixed end coupled to the hub and a free end. The impeller can have a stored configuration and a deployed configuration, the blades in the deployed configuration extending away from the hub, and the blades in the stored configuration being compressed against the hub.
Description
BACKGROUND OF THE INVENTION
Field of the Invention

This application is directed to pumps for mechanical circulatory support of a heart. In particular, this application is directed to various implementations of an impeller that can be used in a catheter pump.


Description of the Related Art

Heart disease is a major health problem that has high mortality rate. Physicians increasingly use mechanical circulatory support systems for treating heart failure. The treatment of acute heart failure requires a device that can provide support to the patient quickly. Physicians desire treatment options that can be deployed quickly and minimally-invasively.


Intra-aortic balloon pumps (IABP) are currently the most common type of circulatory support devices for treating acute heart failure. IABPs are commonly used to treat heart failure, such as to stabilize a patient after cardiogenic shock, during treatment of acute myocardial infarction (MI) or decompensated heart failure, or to support a patient during high risk percutaneous coronary intervention (PCI). Circulatory support systems may be used alone or with pharmacological treatment.


In a conventional approach, an IABP is positioned in the aorta and actuated in a counterpulsation fashion to provide partial support to the circulatory system. More recently minimally-invasive rotary blood pump have been developed in an attempt to increase the level of potential support (i.e. higher flow). A rotary blood pump is typically inserted into the body and connected to the cardiovascular system, for example, to the left ventricle and the ascending aorta to assist the pumping function of the heart. Other known applications pumping venous blood from the right ventricle to the pulmonary artery for support of the right side of the heart. An aim of acute circulatory support devices is to reduce the load on the heart muscle for a period of time, to stabilize the patient prior to heart transplant or for continuing support.


There is a need for improved mechanical circulatory support devices for treating acute heart failure. Fixed cross-section ventricular assist devices designed to provide near full heart flow rate are either too large to be advanced percutaneously (e.g., through the femoral artery without a cutdown) or provide insufficient flow.


There is a need for a pump with improved performance and clinical outcomes. There is a need for a pump that can provide elevated flow rates with reduced risk of hemolysis and thrombosis. There is a need for a pump that can be inserted minimally-invasively and provide sufficient flow rates for various indications while reducing the risk of major adverse events. In one aspect, there is a need for a heart pump that can be placed minimally-invasively, for example, through a 15 FR or 12 FR incision. In one aspect, there is a need for a heart pump that can provide an average flow rate of 4 Lpm or more during operation, for example, at 62 mmHg of head pressure. While the flow rate of a rotary pump can be increased by rotating the impeller faster, higher rotational speeds are known to increase the risk of hemolysis, which can lead to adverse outcomes and in some cases death. Accordingly, in one aspect, there is a need for a pump that can provide sufficient flow at significantly reduced rotational speeds. These and other problems are overcome by the inventions described herein.


SUMMARY

There is an urgent need for a pumping device that can be inserted percutaneously and also provide full cardiac rate flows of the left, right, or both the left and right sides of the heart when called for.


In one embodiment, an impeller for a pump is disclosed. The impeller can comprise a hub having a proximal end portion and a distal end portion. A blade can be supported by the hub. The blade can have a fixed end coupled to the hub and a free end. Further, the impeller can have a stored configuration when the impeller is at rest, a deployed configuration when the impeller is at rest, and an operational configuration when the impeller rotates. The blade in the deployed and operational configurations can extend away from the hub. The blade in the stored configuration can be compressed against the hub. The blade can include a curved surface having a radius of curvature. The radius of curvature can be larger in the operational configuration than when the impeller is in the deployed configuration.


In another embodiment, a percutaneous heart pump is disclosed. The pump can comprise a catheter body and an impeller coupled to a distal end portion of the catheter body. The impeller can comprise a hub. A blade can be supported by the hub and can have a front end portion and a back end portion. The blade can include a ramped surface at the back end portion. A sheath can be disposed about the catheter body and can have a proximal end and a distal end. The distal end of the sheath can be configured to compress the blade from an expanded configuration to a stored configuration when the distal end of the sheath is urged against the ramped surface of the blade.


In yet another embodiment, a method for storing an impeller is disclosed. The method can comprise urging a sheath against a ramped surface of a back end of a blade of an impeller. The impeller can have one or more blades. Further, the impeller can have a stored configuration and a deployed configuration. Each blade in the stored configuration can be compressed against a hub of the impeller. Each blade in the deployed configuration can extend away from the hub. The method can further comprise collapsing the blade against the hub to urge the impeller into the stored configuration.


In another embodiment, a percutaneous heart pump system is disclosed. The system can comprise an impeller disposed at a distal portion of the system. The impeller can be sized and shaped to be inserted through a vascular system of a patient. The impeller can be configured to pump blood through at least a portion of the vascular system at a flow rate of at least about 3.5 liters per minute when the impeller is rotated at a speed less than about 21,000 revolutions per minute.


In another embodiment, a method of pumping blood through the vascular system of a patient is disclosed. The method can comprise inserting an impeller through a portion of the vascular system of the patient to a heart chamber. The method can further include rotating the impeller at a speed less than about 21,000 revolutions per minute to pump blood through at least a portion of the vascular system at a flow rate of at least about 3.5 liters per minute.


In yet another embodiment, an impeller configured for use in a catheter pump is disclosed. The impeller can comprise a hub having a distal portion, a proximal portion, and a diameter. The impeller can also include a blade having a fixed end at the hub and a free end. The blade can have a height defined by a maximum distance between the hub and the free end. A value relating to a ratio of the blade height to the hub diameter can be in a range of about 0.7 to about 1.45.


In another embodiment, a percutaneous heart pump system is disclosed. The system can comprise an impeller disposed at a distal portion of the system, the impeller sized and shaped to be inserted into a vascular system of a patient through a percutaneous access site having a size less than about 21 FR. The impeller can be configured to pump blood in the vascular system at a flow rate of at least about 3.5 liters per minute.


In another embodiment, a percutaneous heart pump system is disclosed. The system can include an impeller comprising one or more blades in a single row. The impeller can be disposed at a distal portion of the system. The impeller can be sized and shaped to be inserted through a vascular system of a patient. The impeller can be configured to pump blood through at least a portion of the vascular system at a flow rate of at least about 2.0 liters per minute when the impeller is rotated at a speed less than about 21,000 revolutions per minute.





BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the subject matter of this application and the various advantages thereof can be realized by reference to the following detailed description, in which reference is made to the accompanying drawings in which:



FIG. 1 illustrates one embodiment of a catheter pump configured for percutaneous application and operation;



FIG. 2 is a plan view of one embodiment of a catheter adapted to be used with the catheter pump of FIG. 1;



FIGS. 3A-3C illustrate the relative position of an impeller blade and an inner surface of an impeller housing in an undeflected configuration;



FIG. 4 shows the catheter assembly similar to that of FIG. 2 in position within the anatomy;



FIGS. 5A-5F are three-dimensional (3D) perspective views of an impeller according to one embodiment;



FIG. 6 is a 3D perspective view of an impeller according to another embodiment;



FIG. 7 is a 3D perspective view of an impeller according to yet another embodiment;



FIG. 8 is a side view of an impeller according to another embodiment;



FIGS. 9A-9E are side views of impellers according to various embodiments;



FIG. 10A is a side view of an impeller according to yet another embodiment;



FIG. 10B is a 3D perspective view of the impeller of FIG. 10A;



FIG. 11 is a side view of an impeller according to another embodiment.



FIG. 12 is a schematic, side cross-sectional view of an impeller having a hub and one or more blades disposed within a housing.



FIG. 13 is a chart plotting flow rate versus motor speed for the impellers illustrated in FIGS. 10A-10B and 9E.



FIG. 14 is a chart plotting flow rate versus motor speed for an impeller similar to or the same as the impeller of FIGS. 10A-10B, as compared to various conventional microaxial, rotary pumps.





More detailed descriptions of various embodiments of components for heart pumps useful to treat patients experiencing cardiac stress, including acute heart failure, are set forth below.


DETAILED DESCRIPTION

This application is directed to apparatuses for inducing motion of a fluid relative to the apparatus. In particular, the disclosed embodiments generally relate to various configurations for an impeller disposed at a distal portion of a percutaneous catheter pump. For example, FIGS. 1-4 show aspects of an exemplary catheter pump 10 that can provide high performance flow rates. The exemplary pump 10 includes a motor driven by a controller 22. The controller 22 directs the operation of the motor 14 and an infusion system 26 that supplies a flow of infusant or infusate in the pump 10. A catheter system 80 that can be coupled with the motor 14 houses an impeller within a distal portion thereof. In various embodiments, the impeller is rotated remotely by the motor 14 when the pump 10 is operating. For example, the motor 14 can be disposed outside the patient. In some embodiments, the motor 14 is separate from the controller 22, e.g., to be placed closer to the patient. In other embodiments, the motor 14 is part of the controller 22. In still other embodiments, the motor is miniaturized to be insertable into the patient. Such embodiments allow the drive shaft to be much shorter, e.g., shorter than the distance from the aortic valve to the aortic arch (about 5 cm or less). Some examples of miniaturized motors catheter pumps and related components and methods are discussed in U.S. Pat. Nos. 5,964,694; 6,007,478; 6,178,922; and 6,176,848, all of which are hereby incorporated by reference herein in their entirety for all purposes.



FIG. 4 illustrates one use of the exemplary catheter pump 10. A distal portion of the pump 10, which can include an impeller assembly 92, is placed in the left ventricle (LV) of the heart to pump blood from the LV into the aorta. The pump 10 can be used in this way to treat patients with a wide range of conditions, including cardiogenic shock, myocardial infarction, and other cardiac conditions, and also to support a patient during a procedure such as percutaneous coronary intervention. One convenient manner of placement of the distal portion of the pump 10 in the heart is by percutaneous access and delivery using the Seldinger technique or other methods familiar to cardiologists. These approaches enable the pump 10 to be used in emergency medicine, a catheter lab and in other non-surgical settings. Modifications can also enable the pump 10 to support the right side of the heart. Example modifications that could be used for right side support include providing delivery features and/or shaping a distal portion that is to be placed through at least one heart valve from the venous side, such as is discussed in U.S. Pat. Nos. 6,544,216; 7,070,555; and US 2012-0203056A1, all of which are hereby incorporated by reference herein in their entirety for all purposes.



FIG. 2 shows features that facilitate small blood vessel percutaneous delivery and high performance, including up to and in some cases exceeding normal cardiac output in all phases of the cardiac cycle. In particular, the catheter system 80 includes a catheter body 84 and a sheath assembly 88. The impeller assembly 92 is coupled with the distal end of the catheter body 84. The exemplary impeller assembly 92 is expandable and collapsible. In the collapsed state, the distal end of the catheter system 80 can be advanced to the heart, for example, through an artery. In the expanded state, the impeller assembly 92 is able to pump blood at high flow rates. FIGS. 2-4 illustrate the expanded state. The collapsed state can be provided by advancing a distal end 94 of an elongate body 96 distally over the impeller assembly 92 to cause the impeller assembly 92 to collapse. This provides an outer profile throughout the catheter assembly 80 that is of small diameter, for example, to a catheter size of about 12.5 FR in various arrangements. Although various expandable impellers are disclosed herein (e.g., impellers having a stored configuration and a deployed configuration), it should be appreciated that the principles described below may also be applicable to impellers that may not be expandable or collapsible. For example, the impeller parameters described herein may also be applicable to fixed diameter impellers in some arrangements.


In some embodiments, the impeller assembly 92 includes a self-expanding material that facilitates expansion. The catheter body 84 on the other hand preferably is a polymeric body that has high flexibility. When the impeller assembly 92 is collapsed, as discussed above, high forces are applied to the impeller assembly 92. These forces are concentrated at a connection zone, where the impeller assembly 92 and the catheter body 84 are coupled together. These high forces, if not carefully managed can result in damage to the catheter assembly 80 and in some cases render the impeller within the impeller assembly 92 inoperable. Robust mechanical interface, are provided to assure high performance.


The mechanical components rotatably supporting the impeller within the impeller assembly 92 permit high rotational speeds while controlling heat and particle generation that can come with high speeds. The infusion system 26 delivers a cooling and lubricating solution to the distal portion of the catheter system 80 for these purposes. However, the space for delivery of this fluid is extremely limited. Some of the space is also used for return of the infusate. Providing secure connection and reliable routing of infusate into and out of the catheter assembly 80 is critical and challenging in view of the small profile of the catheter body 84.


When activated, the pump 10 can effectively increase the flow of blood out of the heart and through the patient's vascular system. In various embodiments disclosed herein, the pump 10 can be configured to produce a maximum flow rate (e.g. low mm Hg) of greater than 4 Lpm, greater than 4.5 Lpm, greater than 5 Lpm, greater than 5.5 Lpm, greater than 6 Lpm, greater than 6.5 Lpm, greater than 7 Lpm, greater than 7.5 Lpm, greater than 8 Lpm, greater than 9 Lpm, or greater than 10 Lpm. In various embodiments, the pump can be configured to produce an average flow rate at about 62 mmHg during operation of greater than 2 Lpm, greater than 2.5 Lpm, greater than 3 Lpm, greater than 3.5 Lpm, greater than 4 Lpm, greater than 4.5 Lpm, greater than 5 Lpm, greater than 5.5 Lpm, or greater than 6 Lpm. In various embodiments, the pump can be configured to produce an average flow rate of at least about 4.25 Lpm at 62 mmHg. In various embodiments, the pump can be configured to produce an average flow rate of at least about 4 Lpm at 62 mmHg. In various embodiments, the pump can be configured to produce an average flow rate of at least about 4.5 Lpm at 62 mmHg.


Various aspects of the pump and associated components are similar to those disclosed in U.S. Pat. Nos. 7,393,181, 8,376,707, 7,841,976, 7,022,100, and 7,998,054 and U.S. Pub. Nos. 2011/0004046, 2012/0178986, 2012/0172655, 2012/0178985, and 2012/0004495, the entire contents of which are incorporated herein for all purposes by reference. In addition, this application incorporates by reference in its entirety and for all purposes the subject matter disclosed in each of the following concurrently filed applications: U.S. patent application Ser. No. 13/802,556, entitled “DISTAL BEARING SUPPORT,” filed on Mar. 13, 2013; U.S. Patent Application No. 61/780,656, entitled “FLUID HANDLING SYSTEM,” filed on Mar. 13, 2013; U.S. patent application Ser. No. 13/801,833, entitled “SHEATH SYSTEM FOR CATHETER PUMP,” filed on Mar. 13, 2013; U.S. patent application Ser. No. 13/801,833, entitled “CATHETER PUMP,” filed on Mar. 13, 2013; and U.S. patent application Ser. No. 13/802,468, entitled “MOTOR ASSEMBLY FOR CATHETER PUMP,” filed on Mar. 13, 2013.


Blade & Impeller Configurations


With reference to FIGS. 3A-3C, an operative device of the pump can include an impeller 300 having one or more blades 303. The one or more blades 303 can extend from an impeller hub 301. It can be desirable to increase the flow rate of the heart pump while ensuring that the impeller 300 can be effectively deployed within a subject. For example, an impeller can include one or more blades 303 that are configured to be inserted into a subject in a stored, or compressed, configuration. When the impeller 300 is positioned in the desired location, e.g., a chamber of a subject's heart as shown in FIG. 4, the blade(s) 303 of the impeller 300 can self-expand into a deployed or expanded configuration, in which the blade(s) 303 extends radially from a hub 301.


As shown in FIGS. 3A-3B, the impeller 300 can be positioned within a cannula or housing 202. A free end of the blades 303 can be separated from the wall W of the housing 202 by a tip gap G. The housing 202 can also have a stored, or compressed configuration, and a deployed or expanded configuration. The housing 202 and impeller 300 may deploy from the stored configurations from within a sheath or sleeve (not shown) into the expanded configuration. In such implementations, the sheath or sleeve can keep the blade(s) 303 and the housing 202 compressed until the blade(s) 303 and housing 202 are urged from within a storage cavity of the sheath or sleeve. Once the blade(s) 303 are released from the storage cavity of the sheath, the blade(s) 303 can self-expand to a deployed configuration using strain energy stored in the blades 303 due to deformation of the blade(s) 303 within the sheath or sleeve. The expandable housing 202 may also self-deploy using stored strain energy after being urged from the sheath.


In the stored configuration, the impeller 300 and housing 202 have a diameter that is preferably small enough to be inserted percutaneously into a patient's vascular system. Thus, it can be advantageous to fold the impeller 300 and housing 202 into a small enough stored configuration such that the housing 202 and impeller 300 can fit within the patient's veins or arteries. In some embodiments, therefore, the impeller 300 can have a diameter in the stored configuration corresponding to a catheter size between about 8 FR and about 21 FR. In one implementation, the impeller 300 can have a diameter in the stored state corresponding to a catheter size of about 9 FR. In other embodiments, the impeller 300 can have a diameter in the stored configuration between about 12 FR and about 21 FR. For example, in one embodiment, the impeller 300 can have a diameter in the stored configuration corresponding to a catheter size of about 12 FR or about 12.5 FR.


When the impeller 300 is positioned within a chamber of the heart, however, it can be advantageous to expand the impeller 300 to have a diameter as large as possible in the expanded or deployed configuration. In general, increased diameter of the impeller 300 can advantageously increase flow rate through the pump. In some implementations, the impeller 300 can have a diameter corresponding to a catheter size greater than about 12 FR in the deployed configuration. In other embodiments, the impeller 300 can have a diameter corresponding to a catheter size greater than about 21 FR in the deployed or expanded configuration.


In various embodiments, it can be important to increase the flow rate of the heart pump while ensuring that the operation of the pump does not harm the subject. For example, increased flow rate of the heart pump can advantageously yield better outcomes for a patient by improving the circulation of blood within the patient. Furthermore, the pump should avoid damaging the subject. For example, if the pump induces excessive shear stresses on the blood and fluid flowing through the pump (e.g., flowing through the cannula), then the impeller can cause damage to blood cells, e.g., hemolysis. If the impeller damages a large number of blood cells, then hemolysis can lead to negative outcomes for the subject, or even death. As will be explained below, various blade parameters can affect the pump's flow rate as well as conditions within the subject's body.


Overview of Various Embodiments

Various embodiments of an impeller for use in a heart pump are disclosed herein. In particular, FIGS. 5A-11 illustrate different configurations for an impeller 300-300J. Each of the disclosed impellers 300-300J can be defined by several different characteristics or parameters that can advantageously improve flow rate while achieving healthy outcomes in a patient. Further, various properties or characteristics of the disclosed impellers may assist in storing and/or deploying the impeller into and/or out from an outer sleeve. Each figure may only illustrate a few of the characteristics of the impeller for ease of illustration. However, it should be appreciated that each illustrated impeller may be associated with all of the characteristics or properties disclosed herein. For example, some figures may illustrate only a few angles or other geometric or structural properties of the impeller, but it should be appreciated that all the impellers disclosed herein may be associated with the disclosed characteristics or properties (see, e.g., the example values given in Tables 1 and 2).


In order to improve patient outcomes, it can be advantageous to provide a heart pump capable of pumping blood at high flow rates while minimizing damage to the blood or the patient's anatomy. For example, it can be desirable to increase flow rate while reducing the motor speed, as higher motor speeds are known to increase the hemolysis risk. Furthermore, for percutaneous insertion heart pump systems, it can be advantageous to make the diameter of the impeller and the cannula as small as possible for insertion into the patient's vasculature. Accordingly, the various impeller embodiments disclosed herein can provide high flow rate while maintaining a diameter small enough for insertion into the patient's vasculature and while reducing the risk that the patient's anatomy and blood are damaged during operation of the pump.


For some or all of the impellers 300-300J illustrated in FIGS. 5A-11, for example, the blades 303 may be formed to have a curved profile with a radius of curvature, R. The radius of curvature R may be sized such that, when the impeller is in the stored or compressed configuration, the blades 303 conform closely to the hub 301. Indeed, in various arrangements, the blades 303 in the stored configuration can have a radius RS sized such that the blades 303 lie against the hub 301 in a low profile so that the insertion diameter of the catheter pump is small enough to be safely inserted through the patient's vasculature. In some embodiments, the radius of curvature R and/or the height h of the blade 303 are selected such that neighboring blades in a particular blade row do not overlap when the impeller is in the stored configuration. By reducing or eliminating blade overlap in the stored configuration, the insertion diameter of the catheter pump can be reduced. In other arrangements, however, neighboring blades may overlap in the stored configuration.


Furthermore, when the impeller is urged out of an external sleeve, the impeller can self-expand into a deployed configuration, in which the impeller is deployed from the sleeve and expanded into a deployed diameter larger than a stored diameter. In various embodiments, the self-expansion of the impeller can be induced by strain energy stored in the blades 303, such as strain or potential energy stored near the root of the blades 303. When the sleeve is urged away from the impeller, the blades 303 can be free to expand into the deployed configuration. It should be appreciated that when the blades 303 are in the deployed configuration, the blade(s) 303 can be in a relaxed state, such that there are no or minimal external forces (such as torque- or flow-induced loads) and internal forces (such as strain energy stored in the blades) applied to the impeller or blades. A radius of curvature RD of the blades 303 in the deployed configuration may be selected to improve flow characteristics of the pump while reducing the risk of hemolysis or other damage to the patient. For example, in some embodiments, the impeller can be molded to form blades 303 having the desired deployed radius of curvature RD, such that in a relaxed (e.g., deployed) state, the blades 303 have a radius of curvature RD that may be selected during manufacturing (e.g., molding). In some arrangements, the radius of curvature RD of the blades in the deployed configuration may be about the same as the radius of curvature RS of the blades in the stored configuration. In other arrangements, however, the radius of curvature of the blades 303 in the stored and deployed configurations may be different.


When the heart pump is activated to rotate the impeller, the impeller and blades 303 may be in an operational configuration. In the operational configuration, the impeller may rotate to drive blood through the housing 202. The rotation of the impeller and/or the flow of blood past the impeller can cause the blades 303 to deform such that an operational radius of curvature Ro may be induced when the impeller is in the operational configuration. For example, when the impeller rotates, the blades 303 may slightly elongate such that the free ends of the blades 303 extend further radially from the hub 301 relative to when the blades 303 are in the deployed configuration. As the blades 303 deform radially outward in the operational configuration, the operational radius of curvature Ro may therefore be larger than the deployed radius of curvature RD. For example, in some embodiments, in the operational configuration, the blades 303 may substantially flatten such that there is little curvature of the blades during operation of the pump. Indeed, in the operational configuration, the blades 303 may extend to an operational height ho that is larger than the height h of the blades 303 when in the deployed configuration (see h as illustrated in the impellers 300-300J of FIG. 5A-11, which are in a deployed or relaxed configuration). In some embodiments, because the blades 303 may be manufactured to be relaxed when in the deployed configuration, the radius of curvature RD and the height h of the blades 303 in the deployed configuration can be selected such that, in the operational configuration, the blades 303 extend radially outward from the hub 301 as far as possible without risking an overly small tip gap G (see FIG. 3C). Flow rate can be improved by enabling the blades 303 to extend radially outward to a greater extent in the operational configuration than in the deployed configuration.


It should be appreciated that the various parameters described herein may be selected to increase flow rate, even while reducing the rotational speed of the impeller. For example, even at relatively low impeller rotational rates of 21,000 revolutions per minute (RPM) or less (e.g., rates in a range of about 18,000 RPM to about 20,000 RPM, or more particularly, in a range of about 18,500 RPM to about 19,500 RPM in some arrangements), the blades 303 can be designed to yield relatively high flow rates in a range of about 4 liters/minute (LPM) to about 5 liters/minute. Conventional percutaneous rotary blood pumps have been found to deliver less than ideal flow rates even at rotational speeds in excess of 40,000 RPM. It should be appreciated that higher impeller rotational rates may be undesirable in some aspects, because the high rate of rotation, e.g., higher RPMs, lead to higher shear rates that generally increase hemolysis and lead to undesirable patient outcomes. By reducing the impeller rotational rate while maintaining or increasing flow rate, the pump in accordance with aspects of the invention can reduce the risk of hemolysis while significantly improving patient outcomes over conventional designs.


Furthermore, to enable percutaneous insertion of the operative device of the pump into the patient's vascular system, the impellers 300-300J disclosed herein in FIGS. 5A-11 may also include a ramped surface at a rearward or proximal end of the blade. As explained herein (see, e.g., FIG. 12), when the external sleeve is urged against the housing 202 (e.g., cannula), the external sleeve can press against the housing 202 and the ramped surface of the impeller to collapse the impeller and blades into the stored configuration. For example, the ramped surface can be used to store the blades and impeller after assembly of the pump for packaging purposes and/or after performing a heart pumping procedure for withdrawal of the pump from the anatomy.


The impellers disclosed herein may be formed of any suitable material and by any suitable process. For example, in preferred embodiments, the impeller is formed from a flexible material, e.g., an elastic material such as a polymer. Any suitable polymer can be used. In some embodiments, for example, Hapflex™ 598, Hapflex™ 798, or Steralloy™ or Thoralon™ may be used in various portions of the impeller body. In some arrangements, the impeller body can be molded to form a unitary body.


Various Impeller Designs


Turning to FIGS. 5A-5F, one embodiment of the impeller 300 is presented. It should be appreciated that FIGS. 5A-5F illustrate the same impeller 300, only showing different views and impeller parameters for ease of illustration. One or more blades 303 can extend from the hub 301, such that a fixed end of the blades 303 is integrally formed with or coupled to the hub 301. The blades 303 can also have a free end located at the tip of the blades 303. As used herein, therefore, it should be appreciated that the blades 303 can have a fixed end coupled to the hub 301 (e.g., at a blade root) and a free end at a tip of the blade 303. In the illustrated embodiments, the hub 301 and blades 303 form a single unitary, or monolithic, body. However, it should be appreciated that in other embodiments, the hub 301 and blades 303 may be formed from separate components or materials. In various implementations, the impeller 300 can include one or more blade rows extending along the hub 301.



FIGS. 5A-5F illustrate the impeller 300 having one blade row and two blades 303. The hub 301 can have a first diameter D1 at a distal end portion of the impeller 300 (e.g., near a leading edge of the blade(s) 303) and a second diameter D2 at a proximal end portion of the impeller 300 (e.g., near a trailing edge of the blade(s) 303). As used herein and as shown in FIG. 5A, for example, a distal end portion of the impeller 300 may be disposed nearer the distal end of the catheter pump, while a proximal end portion of the impeller 300 may be disposed nearer the motor and the insertion site. As explained below, in some implementations, D1 can be less than D2. The hub 301 can also have a length L, and the blades 303 can have a height h, which can be the distance between the hub and the free end of the blades. Further, each blade 303 can have a blade length Lb, which may or may not be the same as the hub length L. As shown in FIG. 5A, the height h may be measured from the hub 301 to the free end of a middle portion of the blades 303 when the impeller is in a deployed or relaxed configuration. The height h may vary along the length of the blades 303, e.g., increasing proximally from a forward or distal end of the blades 303 to a maximum in a middle portion of the blades and decreasing from the middle portion to a rearward or proximal portion of the blades. Furthermore, as explained above, when the impeller 300 rotates and is in an operational configuration, the operational height ho may be larger than the blade height h in the deployed or relaxed configuration, which is illustrated in FIGS. 5A-5F.


Furthermore, each blade 303 can include a suction side 305 and a pressure side 307. In general, fluid can flow from the suction side 305 of the blade 303 toward the pressure side 307 of the blade 303, e.g., from the distal end portion of the impeller 300 to the proximal end portion of the impeller 300. The pressure side 307 can be include a curved, concave surface having a predetermined radius of curvature R, as best seen in FIG. 5C, and as explained above. For example, in FIGS. 5A-5F, the illustrated radius of curvature R corresponds to a relaxed or deployed radius of curvature RD. As explained above, when the impeller 300 rotates, the impeller may be in an operational configuration having an operational radius of curvature Ro that may be larger than the deployed radius of curvature RD. Indeed, in some embodiments, the blades 303 may substantially flatten and elongate radially such that there is little curvature. The elongated blades 303 in the operational configuration may enable for increased flow rate through the pump.


Moreover, each blade 303 can have a thickness designed to improve impeller performance. As shown in FIG. 5B, the leading edge or distal end portion of the blade 303 can have a first thickness t1a at the fixed end of the blade 303, where the blade 303 joins the hub 301, and a second thickness t1b at the free end of the blade 303. Similarly, in FIG. 5C, the trailing edge of the blade 303 can also have a first thickness t2a at the fixed end of the blade 303 and a second thickness t2b at the free end of the blade 303. Example parameters for various blades in FIGS. 5A-11 will be disclosed in the description below and in Tables 1 and 2.


Each blade 303 can wrap around the hub 301 by a desired wrapping angle. The wrapping angle can be measured along the circumference of the hub 301. As shown in the illustrated embodiments, each blade 303 can separately track a helical pattern along the surface of the hub 301 as the blade 303 wraps around the hub 301 along the length L of the hub. Table 2 and the disclosure below illustrate example wrapping angles for blades 303 in various embodiments. The blades can wrap around the hub any suitable number of turns or fractions thereof. Further, a first fillet 311 can be formed at the fixed end of each blade on the suction side 305, and a second fillet 313 can be formed at the fixed end of each blade 303 on the pressure side 307. As shown each fillet 311, 313 can follow the fixed end of each blade 303 as it wraps around the hub 301. As explained below, the first fillet 311 can be sized and shaped to provide support to the blade 303 as the impeller 300 rotates. The second fillet 313 can be sized and shaped to assist in folding or compressing the blade 303 into the stored configuration.


In addition, each blade 303 can form various blade angles α, β, and γ. As shown in FIGS. 5D-F, the blade angles α (referred to herein as an “attack angle α” or a “distal blade angle α”), β (referred to herein as a “middle blade angle β”), and γ (referred to herein as a “proximal blade angle γ”) measure the angles between a blade centerline at various portions of the blade and a plane that is perpendicular to the hub 301. For example, the attack angle α can measure the angle between a plane formed perpendicular to the blade near the distal portion of the blade (e.g., distally along the impeller hub in FIG. 5D) and a plane formed perpendicular to the hub 301. The attack angle α can range between about 30 degrees and about 60 degrees. In some implementations, α can range between about 40 degrees and about 55 degrees. In the implementation of FIG. 5D, for example, α can be in a range of about 48 degrees and about 52 degrees, e.g., about 50 degrees. The middle blade angle β can measure the angle between a plane perpendicular to the blade in a middle portion of the blade and a plane perpendicular to the hub 301. In some implementations, β can range from about 30 degrees to about 45 degrees. In the implementations of FIGS. 5A-5F and 6, for example, β can be in a range of about 35 degrees and about 42 degrees, e.g., about 40 degrees. The proximal blade angle γ can correspond to the angle between a plane perpendicular to the blade in a proximal portion of the blade (e.g., proximal with respect to the hub 301) and a plane perpendicular to the hub 301. In some embodiments, γ can range between about 25 degrees and about 55 degrees. In the illustrated embodiment of FIG. 5F, γ can be in a range of about 30 degrees and about 40 degrees, or about 35 degrees, for example. In some embodiments, the attack angle α can be larger than the middle blade angle β. Further, in some embodiments, the middle blade angle can be larger than the proximal blade angle γ. In some embodiments, the attack angle α can be larger than both the middle blade angle β and the proximal blade angle γ. The blade angles α, β, and γ can be further designed using computational techniques to maintain desired flow characteristics, such as flow rate, pressure head, and rotational speed. For example, the disclosed blade angles can, in various impellers disclosed herein, enable flow rates in a range of about 4 liters/minute to about 5.5 liters/minute, when the impeller rotates at a speed below about 20,000 RPMs (e.g., in a range of about 19,000 RPMs to about 21,000 RPMs in some arrangements). By maintaining a high flow rate at relatively low rotational speeds, the disclosed impellers can achieve desirable patient outcomes while reducing the risk of hemolysis and increasing pump reliability.


Further, the trailing edge of each blade 303 can include a ramp 315 forming a ramp angle θ with the plane perpendicular to the hub 301, as best illustrated in FIG. 5C. The ramp 315 can be shaped such that when the sheath and housing 202 are urged against the ramp 315, or when the blades 303 and housing 202 are pulled proximally relative to and into the sheath, the axial force applied by the sheath can be transferred downward by the ramp 315 to assist in folding the blade 303 against the hub 301. The ramp angle θ can be configured to assist in folding the blade 303 against the hub 301. Further, the cross-sectional curvature and/or axial form of the blades can also be configured to reduce the force needed to collapse the impeller when used in conjunction with the ramp angle θ. For example, the angle that the blades twist around the hub may be configured to direct axial forces applied by the sheath to fold the blades against the hub 301. The radius of curvature R of the blades 303 can also be selected to enable the blades 303 to conform closely to the hub 301, as explained above.


Turning to FIGS. 6-11, other embodiments of the impeller 300 are illustrated. Reference numerals in FIGS. 6-11 generally represent components similar to those of FIGS. 5A-5F. In addition, it should be appreciated that the parameters and angles described above with reference to FIGS. 5A-5F are also present in the impellers disclosed in FIGS. 6-11, even where such parameters or angles are not specifically referenced for ease of illustration. For example, FIG. 6 illustrates an impeller 300A having two blades 303 in one blade row. On the other hand, FIG. 7 illustrates an impeller 300B having three blades 303 in a single blade row. FIG. 8 illustrates another example of an impeller 300C having two blades 303 in one blade row. FIGS. 9A-9C illustrate three impellers 300F-300H, respectively, each having two blades in one row. FIG. 9D illustrates an impeller 3001 having three blades in one row. By contrast, FIG. 9E shows an impeller 300J having four blades total, with two blade rows, each blade row having two blades. FIGS. 10A-10B illustrate yet another impeller 300D having three blades 303 in a single row, while FIG. 11 shows an impeller 300E having two blades 303 in a single row. Tables 1 and 2 include various properties for the impellers 300 shown in the embodiments of FIGS. 5A-5C and 6-11. The impellers 300-300J disclosed herein may have different values for the various parameters and characteristics disclosed herein, and some of the impellers may have improved performance relative to other of the disclosed impellers.


The impellers 300 illustrated in the disclosed embodiments may have other features. For example, for impellers with multiple blade rows, the blade(s) in one row may be angularly clocked relative to the blade(s) in another row. It should be appreciated that the blades may be configured in any suitable shape or may be wrapped around the impeller hub in any manner suitable for operation in a catheter pump system.


Impeller Parameters


As explained above, various impeller parameters can be important in increasing flow rate while ensuring that the pump operates safely within the subject. Further, various properties and parameters of the disclosed impellers 300-300J of FIGS. 5A-11 may enable the impellers to more easily collapse into the stored configuration.


Hub Diameter and Length


One impeller parameter is the size of the hub, e.g., the diameter and/or the length of the hub. As illustrated in FIGS. 5A-11, the hub can be tapered in various embodiments, such that the distal end portion of the hub has a first diameter, D1, and the proximal end portion of the hub has a second diameter, D2. The first and second diameters, D1 and D2 can determine the spacing between the wall W of the housing 202 and the hub 301. Since the housing 202 effectively bounds the area through which blood can flow, the spacing between the hub 301 and the housing wall W may determine the maximum flow rate through the pump. For example, if the hub 301 has a relatively small diameter, then the flow area between the inner wall W of the housing 202 and the hub 301 may be larger than in embodiments with a larger hub diameter. Because the flow area is larger, depending on other impeller parameters, the flow rate through the pump may advantageously be increased.


One of skill in the art will appreciate from the disclosure herein that the impeller parameters may be varied in accordance with the invention. The hub diameter can vary. In some embodiments, D1 can range between about 0.06 inches and about 0.11 inches. D2 can range between about 0.1 inches and about 0.15 inches. For example, in the impeller shown in FIGS. 5A-5F, D1 can be about 0.081 inches, and D2 can be about 0.125 inches. In the implementation of FIGS. 10A and 10B, D1 can be in a range of about 0.08 inches and about 0.09 inches (e.g., about 0.0836 inches in some arrangements), and D2 can be in a range of about 0.12 inches and about 0.13 inches (e.g., about 0.125 inches in some arrangements).


Moreover, the length, Lb, of each blade can be designed in various embodiments to achieve a desired flow rate and pressure head. In general, longer blades can have higher flow rates and pressure heads. Without being limited by theory, it is believed that longer blades can support more blade material and surface area to propel the blood through the cannula. Thus, both the length of the blades and the first and second diameters D1 and D2 can be varied to achieve optimal flow rates. For example, D1 can be made relatively small while Lb can be made relatively long to increase flow rate.


Blade Height


Another impeller parameter is the height h of the blades of the impeller in the deployed, or relaxed, configuration. The height h of the blades can be varied to achieve a stable flow field and to reduce turbulence, while ensuring adequate flow rate. For example, in some embodiments, the blade can be formed to have a height h large enough to induce adequate flow through the cannula. However, because the blades are preferably flexible so that they can fold against the hub in the stored configuration, rotation of the impeller may also cause the blades to flex radially outward due to centrifugal forces. As explained above with respect to FIGS. 3A-3C, the tip gap G between the wall W of the housing 202 and the free ends of the blades can be quite small. If the blades 303 flex outwardly by a substantial amount when the impeller 300 rotates, then the distal ends of the blades 303 may impact the housing wall W, which can damage blood cells passing by. Thus, the height h may also be formed to be sufficiently small such that, upon rotation of the impeller 300, deformation of the blades 300 still maintains adequate tip gap G.


On the other hand, as explained above, the height h of the blades 303 in the deployed configuration can be selected such that when the impeller rotates, the tip or free end of the blades 303 can extend or elongate to an operational height ho, which extends further radially than when in the deployed configuration, in order to increase flow rate. Thus, as explained herein, the height h and the radius of curvature RD of the blades 303 in the deployed configuration can be selected to both increase flow rate while reducing the risk of hemolysis caused by inadequate tip gap G.


In various implementations, the height of the blades near the middle of the impeller hub can range between about 0.06 inches and about 0.15 inches, for example, in a range of about 0.09 inches to about 0.11 inches. Of course, the height of the blades can be designed in conjunction with the design of the hub diameters and length, and with the radius of curvature R. As an example, for the impeller in FIGS. 5A-5C, the height h of the blade near the middle of the impeller hub can be in a range of about 0.09 inches and about 0.1 inches (e.g., about 0.0995 inches in some arrangements). In the impeller of FIGS. 10A-10B, the height h of the blade can be in a range of about 0.1 inches and about 0.11 inches (e.g., about 0.107 inches in some arrangements). Other example blade heights may be seen in Table 1.


Number of Blades


As mentioned above, impellers 300 can have any suitable number of blades 303. In general, in impellers with more blades 303, the flow rate of blood flowing through the cannula or housing 202 can be advantageously increased while reducing the required angular velocity of the drive shaft. Thus, absent other constraints, it can be advantageous to use as many blades as possible to maximize flow rate. However, because the impellers disclosed herein can be configured to fold against the hub 301 in the stored configuration for insertion into a patient's vasculature, using too many blades 303 can increase the overall volume of the impeller in the stored configuration. If the thickness of the impeller 300 in the stored configuration exceeds the diameter of the sheath or sleeve (or the diameter of the patient's artery or vein), then the impeller 300 may not collapse into the sheath for storing.


Moreover, increasing the number of blades 303 accordingly increases the number of shear regions at the free end of the blades 303. As the impeller 300 rotates, the free ends of the blades 303 induce shear stresses on the blood passing by the blades 303. In particular, the tip or free edge of the blades 303 can induce significant shear stresses. By increasing the overall number of blades 303, the number of regions with high shear stresses are accordingly increased, which can disadvantageously cause an increased risk of hemolysis in some situations. Thus, the number of blades can be selected such that there is adequate flow through the pump, while ensuring that the impeller 300 can still be stored within the sheath and that the blades 303 do not induce excessive shear stresses. In various arrangements, for example, an impeller having three blades (such as the impellers shown in FIGS. 7, 9D, and 10A-10B) can achieve an appropriate balance between increased flow rate and reduced risk of hemolysis.


Radius of Curvature


Yet another design parameter for the impeller is the radius of curvature, R, of the blades 303 on the pressure side 307 of the blades, as explained in detail above. As shown in FIGS. 5A-11, the illustrated impellers 300-300J are in the deployed configuration, such that the illustrated R corresponds to the deployed radius of curvature RD. The radius of curvature R can be designed to minimize turbulence, while increasing flow rate. Turbulence can disadvantageously dissipate energy as the impeller rotates, which can reduce the flow rate. In general, higher curvature on the pressure side 307 of the blades 303 can increase turbulence. Moreover, the radius of curvature R can be designed to conform to the hub 301 such that, when the impeller is compressed by the sheath or sleeve, the curved pressure side 307 of the blade 303 conforms to the curvature of the hub 301 when the blades 303 are folded against the hub. Thus, the radius of curvature R of the blades can be designed to both reduce turbulent flow and to assist in folding the blades against the hub to ensure that the impeller 300 fits within the sheath in the stored configuration.


In addition, as explained above, when the impeller rotates and is in the operational configuration, the free end of the blades 303 may extend radially outward such that the radius of curvature in the operational configuration, R0, may be higher than the radius of curvature in the operational configuration, RD, which is illustrated as R in FIGS. 5A-11. Indeed, the straightening and elongation of the blades 303 in the operational configuration may advantageously increase flow rate through the pump system.


The radius of curvature can range between about 0.06 inches and about 0.155 inches in various embodiments. In some embodiments, the radius of curvature can range between about 0.09 inches and about 0.14 inches. For example, in the implementation of FIGS. 5A-5C, the cross-sectional radius of curvature R at the leading edge of the blades can be in a range of about 0.11 inches and about 0.13 inches (e.g., about 0.12 inches in some arrangements). By comparison, the radius of curvature R of the leading edge of the blades in the impeller 300 shown in FIGS. 10A-10B (in the deployed configuration) can be in a range of about 0.13 inches to about 0.14 inches (e.g., about 0.133 inches in some arrangements). Other curvatures may be suitable in various embodiments. Table 2 illustrates example values for the radius of curvature R of various embodiments disclosed herein, when the impellers are in the deployed configuration.


Blade Thickness


In addition, the thickness of the blades 303 can be controlled in various implementations. In general, the thickness of the blades can range between about 0.005 inches and about 0.070 inches in some embodiments, for example in a range of about 0.01 inches to about 0.03 inches. It should be appreciated that the thickness can be any suitable thickness. The thickness of the blade 303 can affect how the blade 303 collapses against the hub 301 when compressed into the stored configuration and how the blade deforms when rotating in an operational configuration. For example, thin blades can deform more easily than thicker blades. Deformable blades can be advantageous when they elongate or deform by a suitable amount to increase flow rate, as explained above. However, as explained above, if the blade 303 deforms outward by an excessive amount, then the free end of the blade can disadvantageously contact the inner wall of the housing 202 when the impeller 300 rotates. On the other hand, it can be easier to fold thin blades against the hub 301 because a smaller force can sufficiently compress the blades 303. Thus, it can be important in some arrangements to design a blade sufficiently stiff such that the blade 303 does not outwardly deform into the cannula or housing 202, while still ensuring that the blade 303 is sufficiently flexible such that it can be easily compressed into the stored configuration and such that it deforms enough to achieve desired flow rates.


In some embodiments, the thickness of each blade can vary along the height h of the blade. For example, the blades can be thinner at the root of the blade 303, e.g., near the hub 301, and thicker at the free end of the blade 303, e.g., near the wall W of the cannula housing 202. As best seen in FIGS. 5B-5C, for example, the leading edge of the blade can have a first thickness t1a at the fixed end of the blade 303 and a second thickness t1b at the free end of the blade 303. Moreover, the trailing edge of the blade 303 can have a first thickness t2a at the fixed end of the blade 303 and a second thickness t2b at the free end of the blade 303. Because the blades 303 are relatively thin near the hub 301, the blades 303 can be easily folded into the stored configuration due to their increased flexibility near the hub 301. Because the blades 303 are relatively thick at the free end (e.g., near the cannula wall W), the blades 303 may deform a suitable amount when the impeller rotates, reducing the risk that the blades 303 will contact or impact the wall W, which can accordingly reduce the risk of hemolysis, while deforming enough to achieve desirable flow rates. Moreover, in some embodiments, the thickness may vary continuously, such that there are no steps or discontinuities in the thickness of the blade. For example, even though the free end of the blades may be thicker in some embodiments, the thickness can continuously increase along the height of the blade.


As an example, the first thickness t1a of the leading edge of the blade in FIGS. 5A-5C can be in a range of about 0.016 inches to about 0.023 inches near the hub (e.g., about 0.02 inches at the hub in some arrangements), while the second thickness t1b can be in a range of about 0.022 inches to about 0.028 inches at the free end (e.g., about 0.025 inches at the free end in some arrangements). Further, at the trailing edge of the blade of FIGS. 5A-5C, the first thickness t2a can be in a range of about 0.016 inches to about 0.023 inches near the hub (e.g., about 0.02 inches at the hub in some arrangements), and the second thickness t2b can be in a range of about 0.03 inches to about 0.04 inches at the free end (e.g., about 0.035 inches at the free end in some arrangements). As another example, for the blade of FIGS. 10A-10B, the first thickness t1a of the leading edge can be in a range of about 0.022 inches to about 0.028 inches at the hub (e.g., about 0.025 inches near the hub in some arrangements), and the second thickness t1b can be in a range of about 0.022 inches to about 0.028 inches at the free end (e.g., about 0.025 inches at the free end in some arrangements). At the trailing edge of the blade of FIGS. 10A-10B, the first thickness t2a can be in a range of about 0.016 inches to about 0.023 inches at the hub (e.g., about 0.02 inches in some arrangements), and the second thickness t2b can be in a range of about 0.016 inches to about 0.023 inches at the free end (e.g., about 0.02 inches in some arrangements).


Fillets at Root of Blades


As explained above, a first fillet 311 can extend along the suction side 305 of each blade 303 at the proximal end of the blade 303 (e.g., at the root of the blade), and a second fillet 313 can extend along the pressure side 307 of each blade at the proximal end of the blade 303. In general the first fillet 311 can have a larger radius than the second fillet 313. The larger fillet 311 can be configured to apply a restoring force when the impeller 300 rotates in the operational configuration. As the impeller 300 rotates, the blades 303 may tend to deform in the distal direction in some situations (e.g., toward the distal portion of the hub 301). By forming the fillet 311 at the suction side 305 of the blade, the curvature of the fillet can advantageously apply a restoring force to reduce the amount of deformation and to support the blade.


By contrast, the second fillet 313 formed on the pressure side 307 of the blade 303 can have a smaller radius than the first fillet 311. The second fillet 313 can be configured to enhance the folding of the blade against the impeller when the blades 303 are urged into the stored configuration.


The radius r of each fillet can be any suitable value. For example, the radius r1 of the first fillet 311 can range between about 0.006 inches and about 0.035 inches. The radius r2 of the second fillet 313 can range between about 0.001 inches and about 0.010 inches. Other fillet radiuses may be suitable. For the implementation of FIGS. 5A-5C, for example, the radius r1 of the first fillet 311 can be about 0.015 inches, and the radius r2 of the second fillet 313 can be about 0.005 inches. By contrast, for the impeller shown in FIGS. 10A-10B, the first fillet 311 can have a radius r1 of about 0.025 inches, and the second fillet 313 can have a radius r2 of about 0.005 inches.


Wrapping Angle


In some implementations, the wrapping angle of each blade can be designed to improve pump performance and to enhance folding of the impeller into the stored configuration. In general, the blades can wrap around the hub at any suitable angle. It has been found that wrapping angles of between about 150 degrees and about 220 degrees can be suitable for folding the blades into the stored configuration. Further, wrapping angles of between about 180 degrees and about 200 degrees can be particularly suitable for folding the blades into the stored configuration.


Ramping Surface


Furthermore, as explained above, the trailing edge or the proximal end of each blade can include a ramp or chamfer formed at an angle θ with a plane perpendicular to the hub 301, as illustrated above in, e.g., FIG. 5C. FIG. 12 is a schematic, side cross-sectional view of an impeller 1200 having a hub 1201 and one or more blades 1203 disposed within a housing 1202, similar to the housing 202 described above. As shown in FIG. 12, the impeller 1200 is in the expanded or deployed configuration. For example, the impeller 1200 may be in the deployed configuration before packaging and shipping to a customer. Alternatively, the impeller 1200 may be in the deployed configuration after pumping blood in a patient and before withdrawal of the pump from the vasculature. As explained above, it can be desirable to compress the impeller 1200 into the stored configuration for inserting or withdrawing the operative device of the pump from the patient. To assist in compressing the impeller 1200 into the stored configuration, the blade(s) 1203 can include a ramp 1215 forming a ramp angle θ with a plane perpendicular to the hub 1201.


An outer sheath or sleeve 1275 can be provided around an elongate body that extends between an operative device of the pump and the motor in the system. The sleeve 1275 can be used to deploy the impeller 1200 from the stored configuration to the deployed configuration and to compress the impeller 1200 from the deployed configuration back into the stored configuration. When compressing and storing the impeller 1200 and the housing 1202, for example, a user, such as a clinician, can advance the sleeve 1275 in the +x-direction, as shown in FIG. 12. When urged in the +x-direction, the sleeve 1275 can bear against a contact portion 1235 of the housing 1202. The contact portion 1235 of the housing 1202 can in turn bear against the ramp 1215. Advantageously, the ramp angle θ can be angled distally such that when the sheath or sleeve 1275 is urged over the impeller 1200 and housing 1202, the contact portion 1235 can contact the angled or ramped edge of the blades to compress the blades against the hub. The ramp angle θ can be any suitable angle. For example, in some embodiments, the ramp angle θ can be between about 30 degrees and about 50 degrees. In the implementation of FIGS. 5A-5C and 12, for example, the chamfer or ramp angle θ of the ramp 1215 can be in a range of about 40 degrees to 50 degrees (e.g., about 45 degrees in some arrangements). In the embodiment of FIGS. 10A-10B, the ramp angle θ of the trailing edge can be in a range of about 35 degrees to 45 degrees (e.g., about 40 degrees in some arrangements). Still other ramp angles θ may be suitable to assist in storing the impeller. In some embodiment, the ramp 1215 can comprise a solid, relatively stiff portion against which the housing 202 and sheath may be advanced.


Improving Patient Outcomes


As explained herein, it can be desirable to pump blood at relatively high flow rates in order to provide adequate cardiac assistance to the patient and to improve patient outcomes. It should be appreciated that, typically, higher impeller rotational speeds may increase flow rates because the impeller is driven at a higher speed. However, one potential disadvantage of high impeller speeds is that blood passing across or over the rotating components (e.g., the impeller and/or impeller shaft or hub) may be damaged by the shearing forces imparted by the relatively rotating components. Accordingly, it is generally desirable to increase flow rates for given rotational impeller speeds.


The various features disclosed herein can enable a skilled artisan to provide an impeller capable of increasing or maintaining flow rates at lower rotational impeller speeds. These improvements are not realized by mere increases in rotational speed or optimization of the impeller design. Rather, the improvements lead to a significant shift in the performance factor of the impeller, which reflect structural advantages of the disclosed impellers.



FIG. 13 is a chart plotting flow rate versus motor speed for the impellers illustrated in FIGS. 10A-10B and 9E. Note that, in the illustrated chart of FIG. 13, however, that the impeller speed is the same as the motor speed, e.g., no clutch is used between the motor and impeller shaft. Thus, the plotted values in FIG. 13 represent flow rates at various impeller rotational speeds. The flow rates were measured by running the impellers on a closed mock loop on the bench with a blood analog. The back pressure (e.g., head pressure or change in pressure across the pump) was at about 62 mmHg for the impellers 300D, 300J of FIGS. 10A-10B and 9E, respectively. The results on the bench top mirror those achieved in animal investigations.


As shown in FIG. 13, the impeller 300D provides for higher flow rates at lower speeds than the impeller 300J of, e.g., FIG. 9E. For example, the impeller 300J of FIG. 9E may be capable of pumping blood at flow rates in a range of about 4.5 liters per minute (LPM) to about 5.5 LPM when the impeller is operating at speeds in a range of about 25,000 revolutions per minute (RPMs) to about 28,000 RPMs. For example, the impeller of FIG. 9E may be capable of pumping blood at a flow rate of about 5.5 LPM when the impeller is operating at speeds in a range of about 26,000 RPMs to about 28,000 RPMs.


In FIG. 13, the flow rate of the impeller 300J can be plotted along a line X, in which flow rate increases with impeller rotational speed, which is the same as motor speed in FIG. 13. With prior designs, increased flow rate can only be achieved by increasing the rotational speed to move along the line X Prior, it was expected that optimization of the impeller design can only realize minor improvements to the flow versus RPM curve. At best, the impeller could be configured to achieve minor improvements at the extremes or with a slight change in the curve X, such that the line or curve X might have a slightly higher slope.


For example, with the impeller 300J of FIG. 9E, the impeller speed at data point X1 is about 21,000 RPM, which yields a flow rate of about 1.9 LPM. With the impeller 300J of FIG. 9E, flow rate can indeed be increased to above about 5 LPM, e.g., about 5.4 LPM, at data point X2, but the impeller rotational speed required to achieve such improvements in flow rate also increases to about 27,000 RPM. Thus, even though the impeller 300J of FIG. 9E can achieve relatively high flow rates, the high flow rates come at the expense of a higher impeller speed, which, as explained above, can cause hemolysis and undesirable patient outcomes.


By contrast, the impeller 300D of FIGS. 10A-10B achieves significant and unexpected performance improvements. The exemplary impeller has been found to achieve dramatically higher flow rates at all rotational speeds. For example, the impeller 300D of FIGS. 10A-10B can achieve flow rates above 4.25 LPM, indeed even above about 5 LPM, while maintaining a low impeller speed of less than about 21,000 RPM (which, by contrast, induced a flow rate of only about 1.9 LPM in the impeller 300J of FIG. 9E). Thus, the design of the impeller 300D of FIGS. 10A-10B can advantageously achieve structural advantages relative to the impeller 300J. Indeed, the curve labeled Yin FIG. 13 illustrates the dramatic shift of the flow rate curve to the left in FIG. 13, which indicates significantly increased flow rates at lower impeller speeds relative to prior impeller designs. The exemplary impeller has also been found to have a dramatically improved head pressure versus flow rate (HQ) performance versus conventional designs.


The exemplary impeller 300D of FIGS. 10A-10B has been found to be capable of pumping blood at flow rates in a range of about 4.5 LPM to about 5.5 LPM when the impeller is operating at speeds in a range of about 19,000 RPM to about 21,000 RPM, e.g., when the impeller is operating at speeds less than about 21,000 RPMs. For instance, the impeller 300D of FIGS. 10A-10B may be capable of pumping blood at a flow rate of about 5.5 LPM when the impeller is operating at speeds in a range of about 20,000 RPMs to about 21,000 RPMs. Further, the impeller 300D of FIGS. 10A-10B may be capable of pumping blood at a flow rate of about 5 LPM when the impeller is rotating at speeds in a range of about 19,000 RPMs to about 21,000 RPMs. In some arrangements, when the impeller is operating at a speed of about 19,500 RPMs, the flow rate may be in a range of about 4.5 LPM to about 5.1 LPM.


Further, the impeller 300D of FIGS. 10A-10B is capable of pumping blood at a flow rate of at least about 3.5 LPM, and/or at least about 4.25 LPM, when the impeller is operating at speeds less than about 21,000 RPMs. For example, the impeller 300D is capable of pumping blood at a flow rate of at least 4.25 LPM when the impeller is operating at speeds in a range of about 18,500 RPM to about 22,000 RPM, for example in a range of about 18,500 RPM to about 21,000 RPM. For example, the impeller 300D is capable of pumping blood at a flow rate in a range of about 4.25 LPM to about 5.5 LPM when the impeller is operating at speeds in a range of about 18,500 RPM to about 21,000 RPM. The flow rates achieved at these impeller speeds may be achieved at a back pressure or head pressure of at least 60 mmHg, e.g., at about 62 mmHg in some embodiments. Further the impeller 300D capable of achieving the performance of FIG. 13 may also be sized and shaped to be inserted into a vascular system of a patient through a percutaneous access site having a catheter size less than about 21 FR.


The impeller 300D of FIGS. 10A-10B may therefore provide a dramatic and unexpected jump in flow rates relative to the impeller 300J of FIG. 9E. The shift in performance allows the impeller 300D to achieve a maximum flow rate far exceeding conventional and/or previous designs and at a rotational speed a mere fraction of that for which conventional pumps are designs. Thus, FIG. 13 illustrates that the impeller 300D of FIGS. 10A-10B yields improved patient outcomes and reduced hemolysis relative to the impeller 300J of FIG. 9E.



FIG. 14 is a chart plotting flow rate versus motor speed (e.g., impeller speed) for an impeller similar to or the same as the impeller 300D of FIGS. 10A-10B, as compared to various conventional microaxial, rotary pumps. In particular, Curve A in FIG. 14 plots flow rate versus motor speed (again, the same as impeller speed in FIG. 14) for the impeller associated with Curve A, according to test data taken using a blood analog at about 62 mmHG back pressure.


Curve B plots approximate flow rate versus motor speed for the heart pump disclosed in the article of J. Stolinski, C. Rosenbaum, Willem Flameng, and Bart Meyns, “The heart-pump interaction: effects of a microaxial blood pump,” International Journal of Artificial Organs, vol: 25 issue: 11 pages: 1082-8, 2002, which is incorporated by reference herein in its entirety and for all purposes. The test data from Curve B was obtained under test conditions having a back pressure of about 60 mmHg.


Curve C plots approximate flow rate versus motor speed for the heart pump disclosed in the article of David M. Weber, Daniel H. Raess, Jose P. S. Henriques, and Thorsten Siess, “Principles of Impella Cardiac Support,” Supplement to Cardiac Interventions Today, August/September 2009, which is incorporated by reference herein in its entirety and for all purposes. The test data from Curve C was obtained under test conditions having a back pressure of about 60 mmHg.


Data point D plots approximate flow rate versus motor speed for the heart pump disclosed in Federal and Drug Administration 510(k) Summary for Predicate Device IMPELLA 2.5 (K112892), prepared on Sep. 5, 2012, which is incorporated by reference herein in its entirety and for all purposes. In particular, for data point D, the disclosed pump was capable of mean flow rates of up to 3.3 LPM at pump speeds of 46,000 RPM at a 60 mmHg differential pressure.


As shown in FIG. 14, the disclosed impeller associated with Curve A can achieve higher flow rate at all impeller speeds relative to the pumps of Curves B, C, and D. The data reflected in FIG. 14 was not all collected by precisely the same methodology in a head-to-head fashion, as noted above. However, the data are shown on a single chart for the convenience of the reader and are still compelling. For example, as discussed above, the back-pressure conditions under which the Curve A data was collected (for impellers disclosed herein) was higher than that collected for the other devices. Were this test condition the same, the results would be all the more impressive. Indeed, data points A1 and A2 of Curve A, for example, provide higher flow rates at significantly lower impeller rotation rates than any of the data points along Curves B-C or at point D (e.g., data points B1, B2, B3, C1, C2). In addition, as shown in FIG. 14, the impeller of Curve A can achieve flow rates of about 7 LPM at impeller speeds of only about 25,000 RPM, as shown by Curve A. By contrast, curves B-C and data point D do not even indicate that the conventional axial pumps can achieve 7 LPM flow rates at any impeller speed. Thus, the impeller associated with Curve A of FIG. 14 can achieve higher flow rates at lower rotational speeds than conventional catheter pumps, such as microaxial, rotary pumps, (e.g., Curves B-C and data point D of FIG. 14). In addition, the disclosed impellers can also be configured to achieve higher maximum flow rates than conventional pumps.


In addition, the data of Curves B-C and data point D of FIG. 14 represent another constraint on the design of conventional rotary pumps. For example, the pump plotted on Curve B has a diameter corresponding to a catheter size of about 21 FR. Flow rates may be increased for the pump of Curve B by increasing the diameter of the pump. However, further increases in pump diameter for the device of Curve B may disadvantageously increase the pump diameter requiring more invasive techniques to position the pump. Thus, increasing flow rate by increasing pump diameter may not be a feasible or desirable alternative for catheter pumps, and/or it may not be desirable for acute heart failure where fast implantation is critically important.


By contrast, as shown in Curve A of FIG. 14, the impeller (e.g., which can be the same as or similar to the impeller 300D disclosed herein) advantageously has an insertion diameter corresponding to a catheter size of less than about 13 FR, e.g., about 12.5 FR in some embodiments, which can enable minimally-invasive insertion techniques, even at higher flow rates and lower impeller rotation rates. Thus, the disclosed impeller of Curve A can provide higher flow rates at lower impeller speeds than conventional microaxial, rotary pumps, and can maintain lower insertion diameters for minimally invasive techniques.


Indeed, the impeller of Curve A may be configured to be inserted into vascular system of a patient through a percutaneous access site having a size less than 21 FR. The impeller of Curve A (e.g., which may be similar to or the same as impeller 300D) may include one or more blades in a single row. In some embodiments, the impeller can be configured to pump blood through at least a portion of the vascular system at a flow rate of at least about 2.0 liters per minute when the impeller is rotated at a speed less than about 21,000 revolutions per minute. In some embodiments, the blades are expandable.


Blade Height-to-Hub Diameter Ratio


In some embodiments, a ratio σ of blade height (h) to hub diameter (D) can be defined. As explained above, the hub 301 can have a first diameter D1 at a distal end portion of the impeller 300 (e.g., near a leading edge of the blade(s) 303) and a second diameter D2 at a proximal end portion of the impeller 300 (e.g., near a trailing edge of the blade(s) 303). As used herein, the ratio σ may be defined relative to a diameter D, which, in some embodiments, may correspond to the first diameter D1 or the second diameter D2, or to an average of D1 and D2. The blade height h may be identified relative to the deployed configuration in some embodiments. As shown in FIGS. 5A-11, the height h may be defined by a maximum distance between the hub 301 and the free end of the blade(s) 303.


The ratio σ may be relatively large compared to conventional impellers. For example, as explained herein, it can be advantageous to provide for an impeller 300 having a low profile suitable, for example, for percutaneous insertion into the patient's vascular system. One way to provide a low profile impeller 300 is to reduce the volume of impeller material that is compressed within the outer sheath, e.g., the sheath within which the impeller 300 is stored during percutaneous delivery and insertion. Impellers having relatively large blade height-to-hub diameter ratios σ may allow for such compact insertion, while maintaining high flow rates. For example, larger blade heights h can allow for the use of smaller hub diameters D, and the larger blade heights h are also capable of inducing high flow rates that are advantageous for catheter pump systems. For example, in some embodiments, the blade height-to-hub diameter ratio σ can be at least about 0.95, at least about 1, at least about 1.1, and/or at least about 1.2, in various arrangements. In some embodiments, for example, the ratio σ can be in a range of about 0.7 to about 1.45 in various embodiments. In particular, the ratio σ can be in a range of about 0.7 to about 1.1 in some embodiments (such as the embodiment of FIGS. 10A-10B, for example). In addition, in some arrangements, the ratio σ can be in a range of about 0.75 to about 1. In some embodiments, the ratio σ can be in a range of about 0.9 to about 1.1.


Example Impeller Parameters


It should be appreciated that the values for the disclosed impeller parameters are illustrative only. Skilled artisans will appreciate that the blade parameters can vary according to the particular design situation. However, in particular embodiments, the blade parameters can include parameter values similar to those disclosed in Tables 1-2 below. Note that length dimensions are in inches and angles are in degrees.

















TABLE 1





FIG.
No. of
D1
D2
h
t1a
t1b
t2a
t2b


Number
Blades
(in.)
(in.)
(in.)
(in.)
(in.)
(in.)
(in.)























5A-5F
2
0.081
0.125
0.0995
0.02
0.025
0.02
0.035


6
2
0.081
0.125
0.1
0.02
0.02
0.015
0.02


7
3
0.0844
0.125
0.1025
0.015
0.015
0.02
0.02


8
2
0.097
0.12
0.107
0.015
0.02
0.015
0.02


10A-10B
3
0.0836
0.125
0.107
0.025
0.025
0.02
0.02


11 
2
0.0798
0.125
0.109
0.03
0.025
0.015
0.02






















TABLE 2





FIG.
β
Wrap Angle
θ
r1
r2
R


Number
(deg)
(deg)
(deg)
(in.)
(in.)
(in.)





















5A-5F
40
210
45
0.015
0.005
0.12


6
40
210
45
0.015
0.005
0.07


7
40
270
46
0.015
0.005
0.133


8
40
200
40
0.015
0.005
0.12


10A-10B
40
220
40
0.025
0.005
0.133


11 
30
210
35
0.015
0.005
0.09









One will appreciate from the description herein that the configuration of the blades may be modified depending on the application. For example, the angle of attack of the blades may be modified to provide for mixed flow, axial flow, or a combination thereof. The exemplary blades of the illustrated figures are dimensioned and configured to improve axial flow and reduce hemolysis risk. The exemplary blades are shaped and dimensioned to achieve the desired pressure head and flow rate. In addition, the single blade row design is thought to reduce the turbulent flow between blade rows with other designs and thus may reduce hemolysis.


Although the inventions herein have been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present inventions. It is therefore to be understood that numerous modifications can be made to the illustrative embodiments and that other arrangements can be devised without departing from the spirit and scope of the present inventions as defined by the appended claims. Thus, it is intended that the present application cover the modifications and variations of these embodiments and their equivalents.

Claims
  • 1. An impeller for a catheter pump, the impeller comprising: a hub having a proximal end portion and a distal end portion; andat least one blade supported by the hub, the at least one blade transitionable between a stored position and a deployed position, the at least one blade having a fixed end coupled to the hub and a free end, wherein the at least one blade comprises: a distal blade angle defined between a plane perpendicular to the free end of the blade near a distal end of the blade and a plane perpendicular to the hub;a proximal blade angle defined between a plane perpendicular to the free end of the blade near a proximal end of the blade and a plane perpendicular to the hub; anda middle blade angle defined between a plane perpendicular to the free end of the blade at a middle portion of the blade and a plane perpendicular to the hub, wherein the distal blade angle is larger than the middle blade angle, and wherein the middle blade angle is larger than the proximal blade angle.
  • 2. The impeller of claim 1, wherein the distal blade angle is in a range from about 30 degrees to about 60 degrees.
  • 3. The impeller of claim 1, wherein the proximal blade angle is in a range from about 30 degrees to about 45 degrees.
  • 4. The impeller of claim 1, wherein the middle blade angle is in a range from about 25 degrees to about 55 degrees.
  • 5. The impeller of claim 1, wherein the distal, proximal, and middle blade angles are selected to achieve relatively high flow rates at relatively low rotational speeds.
  • 6. The impeller of claim 1, wherein the distal, proximal, and middle blade angles are selected to achieve flow rates greater than 3.5 liters/minute.
  • 7. The impeller of claim 1, wherein the distal blade angle is about 50 degrees, the middle blade angle is about 40 degrees, and the proximal blade angle is about 35 degrees.
  • 8. A catheter pump comprising: a catheter; andan impeller mounted at an end of the catheter, the impeller comprising: a hub having a proximal end portion and a distal end portion; andat least one blade supported by the hub, the at least one blade transitionable between a stored position and a deployed position, the at least one blade having a fixed end coupled to the hub and a free end, wherein the at least one blade comprises: a distal blade angle defined between a plane perpendicular to the free end of the blade near a distal end of the blade and a plane perpendicular to the hub;a proximal blade angle defined between a plane perpendicular to the free end of the blade near a proximal end of the blade and a plane perpendicular to the hub; anda middle blade angle defined between a plane perpendicular to the free end of the blade at a middle portion of the blade and a plane perpendicular to the hub, wherein the distal blade angle is larger than the middle blade angle, and wherein the middle blade angle is larger than the proximal blade angle.
  • 9. The catheter pump of claim 8, wherein the distal blade angle is in a range from about 30 degrees to about 60 degrees.
  • 10. The catheter pump of claim 8, wherein the proximal blade angle is in a range from about 30 degrees to about 45 degrees.
  • 11. The catheter pump of claim 8, wherein the middle blade angle is in a range from about 25 degrees to about 55 degrees.
  • 12. The catheter pump of claim 8, wherein the distal, proximal, and middle blade angles are selected to achieve relatively high flow rates at relatively low rotational speeds.
  • 13. The catheter pump of claim 8, wherein the distal, proximal, and middle blade angles are selected to achieve flow rates greater than 3.5 liters/minute.
  • 14. The catheter pump of claim 8, wherein the distal blade angle is about 50 degrees, the middle blade angle is about 40 degrees, and the proximal blade angle is about 35 degrees.
  • 15. A catheter pump comprising: an expandable cannula; andan impeller positioned within the expandable cannula, the impeller comprising: a hub having a proximal end portion and a distal end portion; andat least one blade supported by the hub, the at least one blade transitionable between a stored position and a deployed position, the at least one blade having a fixed end coupled to the hub and a free end, wherein the at least one blade comprises: a distal blade angle defined between a plane perpendicular to the free end of the blade near a distal end of the blade and a plane perpendicular to the hub;a proximal blade angle defined between a plane perpendicular to the free end of the blade near a proximal end of the blade and a plane perpendicular to the hub; anda middle blade angle defined between a plane perpendicular to the free end of the blade at a middle portion of the blade and a plane perpendicular to the hub, wherein the distal blade angle is larger than the middle blade angle, and wherein the middle blade angle is larger than the proximal blade angle.
  • 16. The catheter pump of claim 15, wherein the distal blade angle is in a range from about 30 degrees to about 60 degrees.
  • 17. The catheter pump of claim 15, wherein the proximal blade angle is in a range from about 30 degrees to about 45 degrees.
  • 18. The catheter pump of claim 15, wherein the middle blade angle is in a range from about 25 degrees to about 55 degrees.
  • 19. The catheter pump of claim 15, wherein the distal, proximal, and middle blade angles are selected to achieve relatively high flow rates at relatively low rotational speeds.
  • 20. The catheter pump of claim 15, wherein the distal, proximal, and middle blade angles are selected to achieve flow rates greater than 3.5 liters/minute.
INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS

The present application is a Continuation of U.S. patent application Ser. No. 17/013,066, filed on Sep. 4, 2020, which is a Continuation of U.S. patent application Ser. No. 16/026,995, filed on Jul. 3, 2018, and issued as U.S. Pat. No. 10,765,789, which is a Continuation of Ser. No. 15/589,366, filed on May 8, 2017, and issued as U.S. Pat. No. 10,039,872, which is a Continuation of U.S. patent application Ser. No. 15/142,522, filed on Apr. 29, 2016, and issued as U.S. Pat. No. 9,675,740, which is a Continuation of U.S. patent application Ser. No. 14/401,096, filed on Nov. 13, 2014 and issued as U.S. Pat. No. 9,327,067, which claims the benefit of priority to P.C.T. Application No. PCT/US2013/040809, filed on May 13, 2013, which claims the benefit of priority to U.S. patent application Ser. No. 13/802,570, filed on Mar. 13, 2013 and issued as U.S. Pat. No. 8,721,517, which claims the benefit of priority to U.S. Provisional Patent Application No. 61/667,875, filed on Jul. 3, 2012, and U.S. Provisional Patent Application No. 61/646,827, filed on May 14, 2012, all of which are hereby incorporated by reference herein. Any and all applications not listed above for which a foreign or domestic priority claim is identified in the Application Data Sheet as filed with the present application are hereby incorporated by reference under 37 CFR 1.57.

US Referenced Citations (596)
Number Name Date Kind
1002833 Giddings Sep 1911 A
1031629 De Los Rios Jul 1912 A
1814175 Miller Jul 1931 A
1902418 Pilgrim Mar 1933 A
2356659 Paiva Aug 1944 A
2649052 Weyer Aug 1953 A
2664050 Abresch Dec 1953 A
2684035 Kemp Jul 1954 A
2789511 Doble Apr 1957 A
2896926 Chapman Jul 1959 A
2935068 Shearman May 1960 A
3080824 Boyd Mar 1963 A
3455540 Marcmann Jul 1969 A
3510229 Smith May 1970 A
3812812 Hurwitz May 1974 A
3860968 Shapiro Jan 1975 A
3904901 Renard et al. Sep 1975 A
3995617 Watkins et al. Dec 1976 A
4115040 Knorr Sep 1978 A
4129129 Amrine Dec 1978 A
4135253 Reich et al. Jan 1979 A
4143425 Runge Mar 1979 A
4149535 Volder Apr 1979 A
4304524 Coxon Dec 1981 A
D264134 Xanthopoulos Apr 1982 S
4382199 Isaacson May 1983 A
4392836 Sugawara Jul 1983 A
4458366 MacGregor et al. Jul 1984 A
4537561 Xanthopoulos Aug 1985 A
4540402 Aigner Sep 1985 A
4560375 Schulte et al. Dec 1985 A
4589822 Clausen et al. May 1986 A
4625712 Wampler Dec 1986 A
4655745 Corbett et al. Apr 1987 A
4673334 Allington et al. Jun 1987 A
4686982 Nash Aug 1987 A
4696667 Masch Sep 1987 A
4704121 Moise Nov 1987 A
4728319 Masch et al. Mar 1988 A
4753221 Kensey et al. Jun 1988 A
4769006 Papantonakos Sep 1988 A
4817586 Wampler Apr 1989 A
4846152 Wampler et al. Jul 1989 A
4895557 Moise et al. Jan 1990 A
4900227 Trouplin Feb 1990 A
4902272 Milder et al. Feb 1990 A
4906229 Wampler Mar 1990 A
4908012 Moise et al. Mar 1990 A
4919647 Nash Apr 1990 A
4944722 Carriker et al. Jul 1990 A
4955856 Phillips Sep 1990 A
4957504 Chardack Sep 1990 A
4964864 Summers et al. Oct 1990 A
4969865 Hwang et al. Nov 1990 A
4976270 Parl et al. Dec 1990 A
4985014 Orejola Jan 1991 A
4994017 Yozu Feb 1991 A
4995857 Arnold Feb 1991 A
5000177 Hoffmann et al. Mar 1991 A
5021048 Buckholtz Jun 1991 A
5044902 Malbec Sep 1991 A
5045072 Castillo et al. Sep 1991 A
5049134 Golding et al. Sep 1991 A
5059174 Vaillancourt Oct 1991 A
5061256 Wampler Oct 1991 A
5089016 Millner et al. Feb 1992 A
5092844 Schwartz et al. Mar 1992 A
5098256 Smith Mar 1992 A
5106368 Uldall et al. Apr 1992 A
5112200 Isaacson et al. May 1992 A
5112292 Hwang et al. May 1992 A
5112349 Summers et al. May 1992 A
5129883 Black Jul 1992 A
5142155 Mauze et al. Aug 1992 A
5147186 Buckholtz Sep 1992 A
5163910 Schwartz et al. Nov 1992 A
5169378 Figuera Dec 1992 A
5171212 Buck et al. Dec 1992 A
5190528 Fonger et al. Mar 1993 A
5195960 Hossain et al. Mar 1993 A
5201679 Velte, Jr. et al. Apr 1993 A
5211546 Isaacson et al. May 1993 A
5221270 Parker Jun 1993 A
5234407 Teirstein et al. Aug 1993 A
5234416 Macaulay et al. Aug 1993 A
5290227 Pasque Mar 1994 A
5300112 Barr Apr 1994 A
5312341 Turi May 1994 A
5344443 Palma et al. Sep 1994 A
5346458 Affeld Sep 1994 A
5360317 Clausen et al. Nov 1994 A
5376114 Jarvik Dec 1994 A
5393197 Lemont et al. Feb 1995 A
5393207 Maher et al. Feb 1995 A
5405341 Martin Apr 1995 A
5405383 Barr Apr 1995 A
5415637 Khosravi May 1995 A
5437541 Vainrub Aug 1995 A
5449342 Hirose et al. Sep 1995 A
5458459 Hubbard et al. Oct 1995 A
5490763 Abrams et al. Feb 1996 A
5505701 Anaya Fernandez de Lomana et al. Apr 1996 A
5527159 Bozeman, Jr. et al. Jun 1996 A
5533957 Aldea Jul 1996 A
5534287 Lukic Jul 1996 A
5554114 Wallace et al. Sep 1996 A
5586868 Lawless et al. Dec 1996 A
5588812 Taylor et al. Dec 1996 A
5609574 Kaplan et al. Mar 1997 A
5613935 Jarvik Mar 1997 A
5643226 Cosgrove et al. Jul 1997 A
5678306 Bozeman, Jr. et al. Oct 1997 A
5692882 Bozeman, Jr. et al. Dec 1997 A
5702418 Ravenscroft Dec 1997 A
5704926 Sutton Jan 1998 A
5707218 Maher et al. Jan 1998 A
5722930 Larson, Jr. et al. Mar 1998 A
5725513 Ju et al. Mar 1998 A
5725570 Heath Mar 1998 A
5730628 Hawkins Mar 1998 A
5735897 Buirge Apr 1998 A
5738649 Macoviak Apr 1998 A
5741234 Aboul-Hosn Apr 1998 A
5741429 Donadio et al. Apr 1998 A
5746709 Rom et al. May 1998 A
5749855 Reitan May 1998 A
5755784 Jarvik May 1998 A
5776111 Tesio Jul 1998 A
5776161 Globerman Jul 1998 A
5776190 Jarvik Jul 1998 A
5779721 Nash Jul 1998 A
5807311 Palestrant Sep 1998 A
5814011 Corace Sep 1998 A
5824070 Jarvik Oct 1998 A
5851174 Jarvik et al. Dec 1998 A
5859482 Crowell et al. Jan 1999 A
5868702 Stevens et al. Feb 1999 A
5868703 Bertolero et al. Feb 1999 A
5888241 Jarvik Mar 1999 A
5888242 Antaki et al. Mar 1999 A
5911685 Siess et al. Jun 1999 A
5921913 Siess Jul 1999 A
5927956 Lim et al. Jul 1999 A
5941813 Sievers et al. Aug 1999 A
5951263 Taylor et al. Sep 1999 A
5957941 Ream Sep 1999 A
5964694 Siess et al. Oct 1999 A
5993420 Hyman et al. Nov 1999 A
6007478 Siess et al. Dec 1999 A
6007479 Rottenberg et al. Dec 1999 A
6015272 Antaki et al. Jan 2000 A
6015434 Yamane Jan 2000 A
6018208 Maher et al. Jan 2000 A
6027863 Donadio Feb 2000 A
6053705 Schoeb et al. Apr 2000 A
6056719 Mickley May 2000 A
6058593 Siess May 2000 A
6059760 Sandmore et al. May 2000 A
6068610 Ellis et al. May 2000 A
6071093 Hart Jun 2000 A
6083260 Aboul-Hosn Jul 2000 A
6086527 Talpade Jul 2000 A
6086570 Aboul-Hosn et al. Jul 2000 A
6106494 Saravia et al. Aug 2000 A
6109895 Ray et al. Aug 2000 A
6113536 Aboul-Hosn et al. Sep 2000 A
6123659 Le Blanc et al. Sep 2000 A
6123725 Aboul-Hosn Sep 2000 A
6132363 Freed et al. Oct 2000 A
6135729 Aber Oct 2000 A
6135943 Yu et al. Oct 2000 A
6136025 Barbut et al. Oct 2000 A
6139487 Siess Oct 2000 A
6152704 Aboul-Hosn et al. Nov 2000 A
6162194 Shipp Dec 2000 A
6176822 Nix et al. Jan 2001 B1
6176848 Rau et al. Jan 2001 B1
6178922 Denesuk et al. Jan 2001 B1
6186665 Maher et al. Feb 2001 B1
6190304 Downey et al. Feb 2001 B1
6190357 Ferrari et al. Feb 2001 B1
6200260 Bolling Mar 2001 B1
6203528 Deckert et al. Mar 2001 B1
6210133 Aboul-Hosn et al. Apr 2001 B1
6210318 Lederman Apr 2001 B1
6210397 Aboul-Hosn et al. Apr 2001 B1
6214846 Elliott Apr 2001 B1
6217541 Yu Apr 2001 B1
6227797 Watterson et al. May 2001 B1
6228063 Aboul Hosn May 2001 B1
6234960 Aboul-Hosn et al. May 2001 B1
6234995 Peacock, III May 2001 B1
6245007 Bedingham et al. Jun 2001 B1
6245026 Campbell et al. Jun 2001 B1
6247892 Kazatchkov et al. Jun 2001 B1
6248091 Voelker Jun 2001 B1
6254359 Aber Jul 2001 B1
6254564 Wilk et al. Jul 2001 B1
6287319 Aboul-Hosn et al. Sep 2001 B1
6287336 Globerman et al. Sep 2001 B1
6295877 Aboul-Hosn et al. Oct 2001 B1
6299635 Frantzen Oct 2001 B1
6305962 Maher et al. Oct 2001 B1
6387037 Bolling et al. May 2002 B1
6395026 Aboul-Hosn et al. May 2002 B1
6413222 Pantages et al. Jul 2002 B1
6422990 Prem Jul 2002 B1
6425007 Messinger Jul 2002 B1
6428464 Bolling Aug 2002 B1
6447441 Yu et al. Sep 2002 B1
6454775 Demarais et al. Sep 2002 B1
6468298 Pelton Oct 2002 B1
6494694 Lawless et al. Dec 2002 B2
6503224 Forman et al. Jan 2003 B1
6508777 Macoviak et al. Jan 2003 B1
6508787 Erbel et al. Jan 2003 B2
6517315 Belady Feb 2003 B2
6517528 Pantages et al. Feb 2003 B1
6527699 Goldowsky Mar 2003 B1
6532964 Aboul-Hosn et al. Mar 2003 B2
6533716 Schmitz-Rode et al. Mar 2003 B1
6544216 Sammler et al. Apr 2003 B1
6547519 DeBlanc et al. Apr 2003 B2
6565598 Lootz May 2003 B1
6572349 Sorensen et al. Jun 2003 B2
6609883 Woodard et al. Aug 2003 B2
6610004 Viole et al. Aug 2003 B2
6613008 Aboul-Hosn et al. Sep 2003 B2
6616323 McGill Sep 2003 B2
6623420 Reich et al. Sep 2003 B2
6623475 Siess Sep 2003 B1
6641093 Coudrais Nov 2003 B2
6641558 Aboul-Hosn et al. Nov 2003 B1
6645241 Strecker Nov 2003 B1
6652548 Evans et al. Nov 2003 B2
6660014 Demarais et al. Dec 2003 B2
6673105 Chen Jan 2004 B1
6692318 McBride Feb 2004 B2
6709418 Aboul-Hosn et al. Mar 2004 B1
6716189 Jarvik et al. Apr 2004 B1
6749598 Keren et al. Jun 2004 B1
6776578 Belady Aug 2004 B2
6776794 Hong et al. Aug 2004 B1
6783328 Lucke et al. Aug 2004 B2
6790171 Gruendeman et al. Sep 2004 B1
6794784 Takahashi et al. Sep 2004 B2
6794789 Siess et al. Sep 2004 B2
6814713 Aboul Hosn et al. Nov 2004 B2
6817836 Nose et al. Nov 2004 B2
6818001 Wulfman et al. Nov 2004 B2
6835049 Ray Dec 2004 B2
6860713 Hoover Mar 2005 B2
6866625 Ayre et al. Mar 2005 B1
6866805 Hong et al. Mar 2005 B2
6887215 McWeeney May 2005 B2
6889082 Bolling et al. May 2005 B2
6901289 Dahl et al. May 2005 B2
6926662 Aboul-Hosn et al. Aug 2005 B1
6935344 Aboul-Hosn et al. Aug 2005 B1
6942611 Siess Sep 2005 B2
6949066 Bearnson et al. Sep 2005 B2
6962488 Davis et al. Nov 2005 B2
6966748 Woodard et al. Nov 2005 B2
6972956 Franz et al. Dec 2005 B2
6974436 Aboul-Hosn et al. Dec 2005 B1
6981942 Khaw et al. Jan 2006 B2
6984392 Bechert et al. Jan 2006 B2
7010954 Siess et al. Mar 2006 B2
7011620 Siess Mar 2006 B1
7014417 Salomon Mar 2006 B2
7018182 O'Mahony et al. Mar 2006 B2
7022100 Aboul-Hosn et al. Apr 2006 B1
7027875 Siess et al. Apr 2006 B2
7037069 Arnold et al. May 2006 B2
7070555 Siess Jul 2006 B2
7122019 Kesten et al. Oct 2006 B1
7125376 Viole et al. Oct 2006 B2
7144365 Bolling et al. Dec 2006 B2
7150711 Nusser et al. Dec 2006 B2
7160243 Medvedev Jan 2007 B2
7172551 Leasure Feb 2007 B2
7175588 Morello Feb 2007 B2
7214038 Saxer et al. May 2007 B2
7229258 Wood et al. Jun 2007 B2
7238010 Hershberger et al. Jul 2007 B2
7241257 Ainsworth et al. Jul 2007 B1
7262531 Li et al. Aug 2007 B2
7264606 Jarvik et al. Sep 2007 B2
7267667 Houde et al. Sep 2007 B2
7284956 Nose et al. Oct 2007 B2
7284958 Dundas et al. Oct 2007 B2
7288111 Holloway et al. Oct 2007 B1
7290929 Smith et al. Nov 2007 B2
7329236 Kesten et al. Feb 2008 B2
7331921 Viole et al. Feb 2008 B2
7335192 Keren et al. Feb 2008 B2
7341570 Keren et al. Mar 2008 B2
7381179 Aboul-Hosn et al. Jun 2008 B2
7393181 McBride et al. Jul 2008 B2
7455497 Lee Nov 2008 B2
7469716 Parrino et al. Dec 2008 B2
7478999 Limoges Jan 2009 B2
7491163 Viole et al. Feb 2009 B2
7534258 Gomez et al. May 2009 B2
7605298 Bechert et al. Oct 2009 B2
7619560 Penna et al. Nov 2009 B2
7633193 Masoudipour et al. Dec 2009 B2
7645225 Medvedev et al. Jan 2010 B2
7657324 Westlund et al. Feb 2010 B2
7682673 Houston et al. Mar 2010 B2
7722568 Lenker et al. May 2010 B2
7731675 Aboul-Hosn et al. Jun 2010 B2
7736296 Siess et al. Jun 2010 B2
7758521 Morris et al. Jul 2010 B2
7766892 Keren et al. Aug 2010 B2
7780628 Keren et al. Aug 2010 B1
7785246 Aboul-Hosn et al. Aug 2010 B2
7811279 John Oct 2010 B2
7819833 Ainsworth et al. Oct 2010 B2
7820205 Takakusagi et al. Oct 2010 B2
7828710 Shifflette Nov 2010 B2
7841976 McBride et al. Nov 2010 B2
7878967 Khanal Feb 2011 B1
7918828 Lundgaard et al. Apr 2011 B2
7927068 McBride et al. Apr 2011 B2
7934912 Voltenburg, Jr. et al. May 2011 B2
7935102 Breznock et al. May 2011 B2
7942804 Khaw May 2011 B2
7942844 Moberg et al. May 2011 B2
7955365 Doty Jun 2011 B2
7993259 Kang et al. Aug 2011 B2
7998054 Bolling Aug 2011 B2
7998190 Gharib et al. Aug 2011 B2
8012079 Delgado Sep 2011 B2
8025647 Siess et al. Sep 2011 B2
8052399 Stemple et al. Nov 2011 B2
8062008 Voltenburg, Jr. et al. Nov 2011 B2
8079948 Shifflette Dec 2011 B2
8110267 Houston et al. Feb 2012 B2
8114008 Hidaka et al. Feb 2012 B2
8123669 Siess et al. Feb 2012 B2
8142400 Rotem et al. Mar 2012 B2
8177703 Smith et al. May 2012 B2
8206350 Mann et al. Jun 2012 B2
8209015 Glenn Jun 2012 B2
8216122 Kung et al. Jul 2012 B2
8235943 Breznock et al. Aug 2012 B2
8236040 Mayberry et al. Aug 2012 B2
8236044 Robaina Aug 2012 B2
8255050 Mohl Aug 2012 B2
8257312 Duffy Sep 2012 B2
8262619 Chebator et al. Sep 2012 B2
8277470 Demarais et al. Oct 2012 B2
8317715 Belleville et al. Nov 2012 B2
8329913 Murata et al. Dec 2012 B2
8333687 Farnan et al. Dec 2012 B2
8348991 Weber et al. Jan 2013 B2
8364278 Pianca et al. Jan 2013 B2
8376707 McBride et al. Feb 2013 B2
8382818 Davis et al. Feb 2013 B2
8388565 Shifflette Mar 2013 B2
8409128 Ferrari Apr 2013 B2
8414645 Dwork et al. Apr 2013 B2
8439859 Pfeffer et al. May 2013 B2
8449443 Rodefeld et al. May 2013 B2
8485961 Campbell et al. Jul 2013 B2
8489190 Pfeffer et al. Jul 2013 B2
8535211 Campbell et al. Sep 2013 B2
8540615 Aboul-Hosn et al. Sep 2013 B2
8545379 Marseille et al. Oct 2013 B2
8545380 Farnan et al. Oct 2013 B2
8579858 Reitan et al. Nov 2013 B2
8585572 Mehmanesh Nov 2013 B2
8591393 Walters et al. Nov 2013 B2
8597170 Walters et al. Dec 2013 B2
8608635 Yomtov et al. Dec 2013 B2
8617239 Reitan Dec 2013 B2
8684904 Campbell et al. Apr 2014 B2
8690749 Nunez Apr 2014 B1
8721516 Scheckel May 2014 B2
8721517 Zeng et al. May 2014 B2
8727959 Reitan et al. May 2014 B2
8734331 Evans et al. May 2014 B2
8784441 Rosenbluth et al. Jul 2014 B2
8790236 LaRose et al. Jul 2014 B2
8795576 Tao et al. Aug 2014 B2
8801590 Mohl Aug 2014 B2
8814776 Hastie et al. Aug 2014 B2
8814933 Siess Aug 2014 B2
8849398 Evans Sep 2014 B2
8944748 Liebing Feb 2015 B2
8992406 Corbett Mar 2015 B2
8998792 Scheckel Apr 2015 B2
9028216 Schumacher et al. May 2015 B2
9089634 Schumacher et al. Jul 2015 B2
9089670 Scheckel Jul 2015 B2
9162017 Evans et al. Oct 2015 B2
9217442 Wiessler et al. Dec 2015 B2
9308302 Zeng Apr 2016 B2
9314558 Er Apr 2016 B2
9327067 Zeng et al. May 2016 B2
9328741 Liebing May 2016 B2
9358330 Schumacher Jun 2016 B2
9381288 Schenck et al. Jul 2016 B2
9421311 Tanner et al. Aug 2016 B2
9446179 Keenan et al. Sep 2016 B2
20020010487 Evans et al. Jan 2002 A1
20020047435 Takahashi et al. Apr 2002 A1
20020094287 Davis Jul 2002 A1
20020107506 McGuckin et al. Aug 2002 A1
20020111663 Dahl et al. Aug 2002 A1
20020151761 Viole et al. Oct 2002 A1
20030018380 Craig et al. Jan 2003 A1
20030023201 Aboul-Hosn et al. Jan 2003 A1
20030100816 Siess May 2003 A1
20030135086 Khaw et al. Jul 2003 A1
20030187322 Siess Oct 2003 A1
20030205233 Aboul-Hosn et al. Nov 2003 A1
20030208097 Aboul-Hosn et al. Nov 2003 A1
20030231959 Snider Dec 2003 A1
20040010229 Houde et al. Jan 2004 A1
20040044266 Siess et al. Mar 2004 A1
20040101406 Hoover May 2004 A1
20040113502 Li et al. Jun 2004 A1
20040116862 Ray Jun 2004 A1
20040152944 Medvedev et al. Aug 2004 A1
20040253129 Sorensen et al. Dec 2004 A1
20050049696 Siess et al. Mar 2005 A1
20050085683 Bolling et al. Apr 2005 A1
20050090883 Westlund et al. Apr 2005 A1
20050095124 Arnold et al. May 2005 A1
20050113631 Bolling et al. May 2005 A1
20050135942 Wood et al. Jun 2005 A1
20050137680 Ortiz et al. Jun 2005 A1
20050165269 Aboul et al. Jul 2005 A9
20050165466 Morris et al. Jul 2005 A1
20050250975 Carrier et al. Nov 2005 A1
20050277912 John Dec 2005 A1
20060005886 Parrino et al. Jan 2006 A1
20060008349 Khaw Jan 2006 A1
20060018943 Bechert et al. Jan 2006 A1
20060036127 Delgado, III et al. Feb 2006 A1
20060058869 Olson et al. Mar 2006 A1
20060062672 McBride Mar 2006 A1
20060063965 Aboul-Hosn et al. Mar 2006 A1
20060089521 Chang Apr 2006 A1
20060155158 Aboul-Hosn Jul 2006 A1
20060167404 Pirovano et al. Jul 2006 A1
20060264695 Viole et al. Nov 2006 A1
20060270894 Viole et al. Nov 2006 A1
20070100314 Keren et al. May 2007 A1
20070142785 Lundgaard et al. Jun 2007 A1
20070156006 Smith et al. Jul 2007 A1
20070203442 Bechert et al. Aug 2007 A1
20070212240 Voyeux et al. Sep 2007 A1
20070217932 Voyeux et al. Sep 2007 A1
20070217933 Haser et al. Sep 2007 A1
20070233270 Weber et al. Oct 2007 A1
20070237739 Doty Oct 2007 A1
20070248477 Nazarifar et al. Oct 2007 A1
20080004645 To et al. Jan 2008 A1
20080004690 Robaina Jan 2008 A1
20080031953 Takakusagi et al. Feb 2008 A1
20080103442 Kesten et al. May 2008 A1
20080103516 Wulfman et al. May 2008 A1
20080103591 Siess May 2008 A1
20080114339 McBride et al. May 2008 A1
20080119943 Armstrong et al. May 2008 A1
20080132748 Shifflette Jun 2008 A1
20080167679 Papp Jul 2008 A1
20080275290 Viole et al. Nov 2008 A1
20080306327 Shifflette Dec 2008 A1
20090018567 Escudero et al. Jan 2009 A1
20090023975 Marseille et al. Jan 2009 A1
20090024085 To et al. Jan 2009 A1
20090053085 Thompson et al. Feb 2009 A1
20090062597 Shifflette Mar 2009 A1
20090073037 Penna et al. Mar 2009 A1
20090087325 Voltenburg, Jr. et al. Apr 2009 A1
20090093764 Pfeffer et al. Apr 2009 A1
20090093765 Glenn Apr 2009 A1
20090093796 Pfeffer et al. Apr 2009 A1
20090099638 Grewe Apr 2009 A1
20090112312 LaRose et al. Apr 2009 A1
20090118567 Siess May 2009 A1
20090163864 Breznock et al. Jun 2009 A1
20090171137 Farnan et al. Jul 2009 A1
20090182188 Marseille et al. Jul 2009 A1
20090234378 Escudero et al. Sep 2009 A1
20100030161 Duffy Feb 2010 A1
20100030186 Stivland Feb 2010 A1
20100041939 Siess Feb 2010 A1
20100047099 Miyazaki et al. Feb 2010 A1
20100087773 Ferrari Apr 2010 A1
20100094089 Litscher et al. Apr 2010 A1
20100127871 Pontin May 2010 A1
20100137802 Yodfat et al. Jun 2010 A1
20100174239 Yodfat et al. Jul 2010 A1
20100191035 Kang et al. Jul 2010 A1
20100197994 Mehmanesh Aug 2010 A1
20100210895 Aboul-Hosn et al. Aug 2010 A1
20100268017 Siess et al. Oct 2010 A1
20100274330 Burwell et al. Oct 2010 A1
20100286210 Murata et al. Nov 2010 A1
20100286791 Goldsmith Nov 2010 A1
20110004046 Campbell et al. Jan 2011 A1
20110004291 Davis et al. Jan 2011 A1
20110009687 Mohl Jan 2011 A1
20110015610 Plahey et al. Jan 2011 A1
20110034874 Reitan et al. Feb 2011 A1
20110071338 McBride et al. Mar 2011 A1
20110076439 Zeilon Mar 2011 A1
20110098805 Dwork et al. Apr 2011 A1
20110106004 Eubanks et al. May 2011 A1
20110152831 Rotem et al. Jun 2011 A1
20110152906 Escudero et al. Jun 2011 A1
20110152907 Escudero et al. Jun 2011 A1
20110218516 Grigorov Sep 2011 A1
20110237863 Ricci et al. Sep 2011 A1
20110257462 Rodefeld Oct 2011 A1
20110270182 Breznock et al. Nov 2011 A1
20110275884 Scheckel Nov 2011 A1
20110300010 Jarnagin et al. Dec 2011 A1
20120004495 Bolling et al. Jan 2012 A1
20120029265 LaRose et al. Feb 2012 A1
20120059213 Spence et al. Mar 2012 A1
20120059460 Reitan Mar 2012 A1
20120083740 Chebator et al. Apr 2012 A1
20120142994 Toellner Jun 2012 A1
20120172654 Bates Jul 2012 A1
20120172655 Campbell et al. Jul 2012 A1
20120172656 Walters et al. Jul 2012 A1
20120178985 Walters et al. Jul 2012 A1
20120178986 Campbell et al. Jul 2012 A1
20120184803 Simon et al. Jul 2012 A1
20120203056 Corbett Aug 2012 A1
20120220854 Messerly et al. Aug 2012 A1
20120224970 Schumacher et al. Sep 2012 A1
20120226097 Smith et al. Sep 2012 A1
20120234411 Scheckel et al. Sep 2012 A1
20120237357 Schumacher et al. Sep 2012 A1
20120245404 Smith et al. Sep 2012 A1
20120265002 Roehn et al. Oct 2012 A1
20130041202 Toellner Feb 2013 A1
20130053622 Corbett Feb 2013 A1
20130053623 Evans et al. Feb 2013 A1
20130066140 McBride et al. Mar 2013 A1
20130085318 Toellner et al. Apr 2013 A1
20130085319 Evans et al. Apr 2013 A1
20130096364 Reichenbach et al. Apr 2013 A1
20130103063 Escudero et al. Apr 2013 A1
20130106212 Nakazumi et al. May 2013 A1
20130129503 McBride et al. May 2013 A1
20130138205 Kushwaha et al. May 2013 A1
20130177409 Schumacher Jul 2013 A1
20130204362 Toellner et al. Aug 2013 A1
20130209292 Baykut et al. Aug 2013 A1
20130237744 Pfeffer et al. Sep 2013 A1
20130245360 Schumacher et al. Sep 2013 A1
20130303831 Evans et al. Nov 2013 A1
20130303969 Keenan et al. Nov 2013 A1
20130303970 Keenan et al. Nov 2013 A1
20130331639 Campbell et al. Dec 2013 A1
20130345492 Pfeffer et al. Dec 2013 A1
20140005467 Farnan et al. Jan 2014 A1
20140010686 Tanner et al. Jan 2014 A1
20140012065 Fitzgerald et al. Jan 2014 A1
20140039465 Schulz et al. Feb 2014 A1
20140051908 Khanal et al. Feb 2014 A1
20140067057 Callaway et al. Mar 2014 A1
20140088455 Christensen et al. Mar 2014 A1
20140148638 LaRose et al. May 2014 A1
20140163664 Goldsmith Jun 2014 A1
20140255176 Bredenbreuker et al. Sep 2014 A1
20140275725 Schenck et al. Sep 2014 A1
20140275726 Zeng Sep 2014 A1
20140301822 Scheckel Oct 2014 A1
20140303596 Schumacher et al. Oct 2014 A1
20150025558 Wulfman et al. Jan 2015 A1
20150031936 LaRose et al. Jan 2015 A1
20150051435 Siess et al. Feb 2015 A1
20150051436 Spanier et al. Feb 2015 A1
20150080743 Siess et al. Mar 2015 A1
20150087890 Spanier et al. Mar 2015 A1
20150141738 Toellner et al. May 2015 A1
20150141739 Hsu May 2015 A1
20150151032 Voskoboynikov et al. Jun 2015 A1
20150209498 Franano et al. Jul 2015 A1
20150250935 Anderson et al. Sep 2015 A1
20150290372 Muller et al. Oct 2015 A1
20150343179 Schumacher et al. Dec 2015 A1
20160184500 Zeng Jun 2016 A1
20160250399 Tiller et al. Sep 2016 A1
20160250400 Schumacher Sep 2016 A1
20160256620 Schekel et al. Sep 2016 A1
20210038788 Zeng Feb 2021 A1
Foreign Referenced Citations (52)
Number Date Country
2701810 Apr 2009 CA
0453234 Oct 1991 EP
0533432 Mar 1993 EP
1207934 May 2002 EP
1393762 Mar 2004 EP
1591079 Nov 2005 EP
2263732 Dec 2010 EP
2298374 Mar 2011 EP
2267800 Nov 1975 FR
2239675 Jul 1991 GB
S48-23295 Mar 1973 JP
S4823295 Mar 1973 JP
S58190448 Nov 1983 JP
H02211169 Aug 1990 JP
H06114101 Apr 1994 JP
H08196624 Aug 1996 JP
H1099447 Apr 1998 JP
H10099447 Apr 1998 JP
3208454 Sep 2001 JP
500877 Sep 2002 TW
8905164 Jun 1989 WO
9526695 Oct 1995 WO
9737697 Apr 1996 WO
9715228 May 1997 WO
12148 Mar 2000 WO
0019097 Apr 2000 WO
0043062 Jul 2000 WO
61207 Oct 2000 WO
0069489 Nov 2000 WO
117581 Mar 2001 WO
0124867 Apr 2001 WO
02070039 Sep 2002 WO
03103745 Dec 2003 WO
2005089674 Sep 2005 WO
2005123158 Dec 2005 WO
2009073037 Jun 2009 WO
2009076460 Jun 2009 WO
2010127871 Nov 2010 WO
2010133567 Nov 2010 WO
2010149393 Dec 2010 WO
2011035926 Mar 2011 WO
2011035929 Mar 2011 WO
2011039091 Apr 2011 WO
2011076439 Jun 2011 WO
2011076441 Jun 2011 WO
2011089022 Jul 2011 WO
2012007140 Jan 2012 WO
2012007141 Jan 2012 WO
2013148697 Oct 2013 WO
2013160407 Oct 2013 WO
2014019274 Feb 2014 WO
2015063277 May 2015 WO
Non-Patent Literature Citations (101)
Entry
Schmitz-Rode et al., “Axial flow catheter pump for circulatory support,” Biomedizinische Technik, 2002, Band 4 7, Erganzungsband 1, Tei I 1, pp. 142-143.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2015/026025, dated Oct. 22, 2015, in 12 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2015/045370, dated Feb. 25, 2016, in 10 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2016/014371, dated Jul. 28, 2016, in 16 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2016/014379, dated Jul. 29, 2016, in 17 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2016/014391, dated Jul. 28, 2016, in 15 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2016/051553, dated Mar. 23, 2017, in 11 pages.
International Search Report received in International Patent Application No. PCT/US2003/004401, dated Jan. 22, 2004, in 7 pages.
International Search Report received in International Patent Application No. PCT/US2003/004853, dated Nov. 10, 2003, in 5 pages.
JOMED Reitan Catheter Pump RCP, Feb. 18, 2003, in 4 pages.
JOMED Reitan Catheter Pump RCP, Percutaneous Circulatory Support, in 10 pages, believed to be published prior to Oct. 15, 2003.
Krishnamani et al., “Emerging Ventricular Assist Devices for Long-Term Cardiac Support,” National Review, Cardiology, Feb. 2010, pp. 71-76, vol. 7.
Kunst et al., “Integrated unit for programmable control of the 21F Hemopump and registration of physiological signals,” Medical & Biological Engineering & Computing, Nov. 1994, pp. 694-696.
Mihaylov et al., “Development of a New Introduction Technique for the Pulsatile Catheter Pump,” Artificial Organs, 1997, pp. 425-427; vol. 21(5).
Mihaylov et al., “Evaluation of the Optimal Driving Mode During Left Ventricular Assist with Pulsatile Catheter Pump in Calves,” Artificial Organs, 1999, pp. 1117-1122; vol. 23(12).
Minimally Invasive Cardiac Assist JOMED Catheter PumpTM, in 6 pages, believed to be published prior to Jun. 16, 1999.
Morgan, “Medical Shape Memory Alloy Applications—The Market and its Products,” Materials Science and Engineering, 2004, pp. 16-23, vol. A 378.
Morsink et al., “Numerical Modelling of Blood Flow Behaviour in the Valved Catheter of the PUCA-Pump, a LVAD,”The International Journal of Artificial Organs, 1997, pp. 277-284; vol. 20(5).
Nishimura et al., “The Enabler Cannula Pump: A Novel Circulatory Support System,” The International Journal of Artificial Organs, 1999, pp. 317-323; vol. 22(5).
Nullity Action against the owner of the German part DE 50 2007 005 015.6 of European patent EP 2 047 872 B1, dated Jul. 13, 2015, in 61 pages.
Petrini et al., “Biomedical Applications of Shape Memory Alloys,” Journal of Metallurgy, 2011, pp. 1-15.
Raess et al., “Impella 2.5,” J. Cardiovasc. Transl. Res., 2009, pp. 168-172, vol. 2(2).
Reitan et al., “Hemodynamic Effects of a New Percutaneous Circulatory Support Device in a Left Ventricular Failure Model,” ASAIO Journal, 2003, pp. 731-736, vol. 49.
Reitan et al., “Hydrodynamic Properties of a New Percutaneous Intra-Aortic Axial Flow Pump,” ASAIO Journal 2000, pp. 323-328.
Reitan, Evaluation of a New Percutaneous Cardiac Assist Device, Department of Cardiology, Faculty of Medicine, Lund University, Sweden, 2002, in 172 pages.
Rothman, “The Reitan Catheter Pump: A New Versatile Approach for Hemodynamic Support”, London Chest Hospital Barts & The London NHS Trust, Oct. 22-27, 2006 (TCT 2006: Transcatheter Cardiovascular Therapeutics 18th Annual Scientific Symposium, Final Program), in 48 pages.
Schmitz-Rode et al., “An Expandable Percutaneous Catheter Pump for Left Ventricular Support,” Journal of the American College of Cardiology, 2005, pp. 1856-1861, vol. 45(11).
Shabari et al., “Improved Hemodynamics with a Novel Miniaturized Intra-Aortic Axial Flow Pump in a Porcine Model of Acute Left Ventricular Dysfunction,” ASAIO Journal, 2013, pp. 240-245; vol. 59.
Sharony et al., “Cardiopulmonary Support and Physiology—The Intra-Aortic Cannula Pump: A Novel Assist Device for the Acutely Failing Heart,” The Journal of Thoracic and Cardiovascular Surgery, Nov. 1992, pp. 924-929, vol. 118(5).
Sharony et al., “Right Heart Support During Off-Pump Coronary Artery Surgery—A Multi-Center Study,” The Heart Surgery Forum, 2002, pp. 13-16, vol. 5(1).
Siess et al., “Basic design criteria for rotary blood pumps,” H. Masuda, Rotary Blood Pumps, Springer, Japan, 2000, pp. 69-83.
Siess et al., “Concept, realization, and first in vitro testing of an intraarterial microaxial blood pump,” Artificial Organs, 1995, pp. 644-652, vol. 19, No. 7, Blackwell Science, Inc., Boston, International Society for Artificial Organs.
Siess et al., “From a lab type to a product: A retrospective view on Impella's assist technology,” Artificial Organs, 2001, pp. 414-421, vol. 25, No. 5, Blackwell Science, Inc., International Society for Artificial Organs.
Siess et al., “System analysis and development of intravascular rotation pumps for cardiac assist,” Dissertation, Shaker Verlag, Aachen, 1999, 39 pages.
Sieß et al., “Hydraulic refinement of an intraarterial microaxial blood pump”, The International Journal of Artificial Organs, 1995, vol. 18, No. 5, pp. 273-285.
Sieß, “Systemanalyse und Entwicklung intravasaler Rotationspumpen zur Herzunterstützung”, Helmholtz-Institut fur Blomedixinische Technik an der RWTH Aachen, Jun. 24, 1998, in 105 pages.
Smith et al., “First-In-Man Study of the Reitan Catheter Pump for Circulatory Support in Patients Undergoing High-Risk Percutaneous Coronary Intervention,” Catheterization and Cardiovascular Interventions, 2009, pp. 859-865, vol. 73(7).
Sokolowski et al., “Medical Applications of Shape Memory Polymers,” Biomed. Mater. 2007, pp. S23-S27, vol. 2.
Stoeckel et al., “Self-Expanding Nitinol Stents—Material and Design Considerations,” European Radiology, 2003, in 13 sheets.
Stolinski et al., “The heart-pump interaction: effects of a microaxial blood pump,” International Journal of Artificial Organs, 2002, pp. 1082-1088, vol. 25, Issue 11.
Supplemental European Search Report received from the European Patent Office in EP Application No. EP 05799883 dated Mar. 19, 2010, 3 pages.
Takagaki et al., “A Novel Miniature Ventricular Assist Device for Hemodynamic Support,” ASAIO Journal, 2001, pp. 412-416, vol. 47.
Throckmorton et al., “Flexible Impeller Blades in an Axial Flow Pump for Intravascular Cavopulmonary Assistance of the Fontan Physiology,” Cardiovascular Engineering and Technology, Dec. 2010, pp. 244-255, vol. 1(4).
Throckmorton et al., “Uniquely shaped cardiovascular stents enhance the pressure generation of intravascular blood pumps,” The Journal of Thoracic and Cardiovascular Surgery, Sep. 2012, pp. 704-709, vol. 133, No. 3.
Verkerke et al., “Numerical Simulation of the PUCA Pump, A Left Ventricular Assist Device,” Abstracts of the XIXth ESAO Congress, The International Journal of Artificial Organs, 1992, p. 543, vol. 15(9).
Verkerke et al., “Numerical Simulation of the Pulsating Catheter Pump: A Left Ventricular Assist Device,” Artificial Organs, 1999, pp. 924-931, vol. 23(10).
Verkerke et al., “The PUCA Pump: A Left Ventricular Assist Device,” Artificial Organs, 1993, pp. 365-368, vol. 17(5).
Wampler et al., “The Sternotomy Hemopump, A Second Generation Intraarterial Ventricular Assist Device,” ASAIO Journal, 1993, pp. M218-M223, vol. 39.
Weber et al., “Principles of Impella Cardiac Support,” Supplemental to Cardiac Interventions Today, Aug./Sep. 2009.
Written Opinion received in International Patent Application No. PCT/US2003/04853, dated Feb. 25, 2004, 5 pages.
“Statistical Analysis and Clinical Experience with the Recover® Pump Systems”, Impella CardioSystems GmbH, Sep. 2005, 2 sheets.
Abiomed—Recovering Hearts. Saving Lives., Impella 2.5 System, Instructions for Use, Jul. 2007, in 86 sheets.
Abiomed, “Impella 5.0 with the Impella Console, Circulatory Support System, Instructions for Use & Clinical Reference Manual,” Jun. 2010, in 122 pages.
Aboul-Hosn et al., “The Hemopump: Clinical Results and Future Applications”, Assisted Circulation 4, 1995, in 14 pages.
Barras et al., “Nitinol—Its Use in Vascular Surgery and Other Applications,” Eur. J. Vase. Endovasc. Surg., 2000, pp. 564-569; vol. 19.
Biscarini et al., “Enhanced Nitinol Properties for Biomedical Applications,” Recent Patents on Biomedical Engineering, 2008, pp. 180-196, vol. 1(3).
Cardiovascular Diseases (CVDs) Fact Sheet No. 317; World Health Organization [Online], Sep. 2011. http://www.who.int/mediacentre/factsheets/fs317/en/index.html, accessed on Aug. 29, 2012.
Compendium of Technical and Scientific Information for the HEMOPUMP Temporary Cardiac Assist System, Johnson & Johnson Interventional Systems, 1988, in 15 pages.
Dekker et al., “Efficacy of a New Intraaortic Propeller Pump vs the Intraaortic Balloon Pump, An Animal Study”, Chest, Jun. 2003, vol. 123, No. 6, pp. 2089-2095.
Duerig et al., “An Overview of Nitinol Medical Applications,” Materials Science Engineering, 1999, pp. 149-160; vol. A273.
European Search Report received in European Patent Application No. 05799883.3, dated May 10, 2011, in 4 pages.
Extended EP Search Report, dated Mar. 15, 2018, for related EP patent application No. EP 15833166.0, in 7 pages.
Extended European Search Report received in European Patent Application No. 07753903.9, dated Oct. 8, 2012, in 7 pages.
Extended European Search Report received in European Patent Application No. 13790890.1, dated Jan. 7, 2016, in 6 pages.
Extended European Search Report received in European Patent Application No. 13791118.6, dated Jan. 7, 2016, in 6 pages.
Extended European Search Report received in European Patent Application No. 13813687.4, dated Feb. 24, 2016, in 6 pages.
Extended European Search Report received in European Patent Application No. 13813867.2, dated Feb. 26, 2016, in 7 pages.
Extended European Search Report received in European Patent Application No. 14764392.8, dated Oct. 27, 2016, in 7 pages.
Extended European Search Report received in European Patent Application No. 14779928.2, dated Oct. 7, 2016, in 7 pages.
Federal and Drug Administration 510(k) Summary for Predicate Device IMPELLA 2.5 (K112892), prepared Sep. 5, 2012.
Grech, “Percutaneous Coronary Intervention. I: History and Development,” BMJ., May 17, 2003, pp. 1080-1082, vol. 326.
Hsu et al., “Review of Recent Patents on Foldable Ventricular Assist Devices,” Recent Patents on Biomedical Engineering, 2012, pp. 208-222, vol. 5.
Ide et al., “Evaluation of the Pulsatility of a New Pulsatile Left Ventricular Assist Device—the Integrated Cardioassist Catheter—in Dogs,” J. of Thorac and Cardiovasc Sur, Feb. 1994, pp. 569-0575, vol. 107(2).
Ide et al., “Hemodynamic Evaluation of a New Left Ventricular Assist Device: An Integrated Cardioassist Catheter as a Pulsatile Left Ventricle—Femoral Artery Bypass,” Blackwell Scientific Publications, Inc., 1992, pp. 286-290, vol. 16(3).
Impella CP®—Instructions for Use & Clinical Reference Manual (United States only), Abiomed, Inc., Jul. 2014, 148 pages, www.abiomed.com.
Impella LD® with the Impella® Controller—Circulatory Support System—Instructions for Use & Clinical Reference Manual (United States only), Abiomed, Inc., Sep. 2010, 132 pages, www.abiomed.com.
International Preliminary Examination Report received in International Patent Application No. PCT/US2003/04401, dated May 18, 2004, in 4 pages.
International Preliminary Examination Report received in International Patent Application No. PCT/US2003/04853, dated Jul. 26, 2004, in 5 pages.
International Preliminary Report on Patentability and Written Opinion of the International Searching Authority received in International Patent Application No. PCT/US2005/033416, dated Mar. 20, 2007, in 7 pages.
International Preliminary Report on Patentability and Written Opinion of the International Searching Authority received in International Patent Application No. PCT/US2007/007313, dated Sep. 23, 2008, in 6 pages.
International Preliminary Report on Patentability and Written Opinion received in International Patent Application No. PCT/US2014/020878, dated Sep. 15, 2015, in 8 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2005/033416, dated Dec. 11, 2006, in 8 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2007/007313, dated Mar. 4, 2008, in 6 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2010/040847, dated Jan. 6, 2011, in 15 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2012/020369, dated Jul. 30, 2012, in 10 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2012/020382, dated Jul. 31, 2012, in 11 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2012/020383, dated Aug. 17, 2012; in 9 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2012/020553, dated Aug. 17, 2012, in 8 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2013/040798, dated Aug. 21, 2013, in 16 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2013/040799, dated Aug. 21, 2013, in 19 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2013/040809, dated Sep. 2, 2013, in 25 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2013/048332, dated Oct. 16, 2013, in 14 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2013/048343, dated Oct. 11, 2013, in 15 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2014/020790, dated Oct. 9, 2014, in 9 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2014/020878, dated May 7, 2014, in 11 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2015/025959, dated Oct. 22, 2015, in 9 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2015/025960, dated Oct. 22, 2015, in 11 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2015/026013, dated Oct. 22, 2015, in 8 pages.
International Search Report and Written Opinion received in International Patent Application No. PCT/US2015/026014, dated Oct. 22, 2015, in 8 pages.
Extended European Search report in EP Patent Application No. 20204760.1, dated Feb. 10, 2021, 8 pages.
Extended European Search report in EP Patent Application No. 20204761.9, dated Feb. 11, 2021, 8 pages.
Related Publications (1)
Number Date Country
20210038788 A1 Feb 2021 US
Provisional Applications (2)
Number Date Country
61667875 Jul 2012 US
61646827 May 2012 US
Continuations (6)
Number Date Country
Parent 17013066 Sep 2020 US
Child 17083503 US
Parent 16026995 Jul 2018 US
Child 17013066 US
Parent 15589366 May 2017 US
Child 16026995 US
Parent 15142522 Apr 2016 US
Child 15589366 US
Parent 14401096 US
Child 15142522 US
Parent 13802570 Mar 2013 US
Child 14401096 US