Patent Application
20140243953
1. Field
Certain embodiments of the present invention are related to medical device delivery systems and methods of using the system.
2. Background Art
Existing medical device delivery systems, such as those for use in percutaneous medical procedures, can allow a medical device to be delivered through a patient's vasculature to a delivery site where it can be implanted within a patient. In some procedures a medical device in the form of a valve prosthesis can be compacted and loaded onto a delivery device for advancement through a patient's vasculature in a transfemoral, transapical, and/or transatrial procedure. There is a continuous need for improved delivery systems for use in percutaneous and other delivery techniques.
In some situations, it can be desirable to improve consistency and predictability of delivery systems. These improvements can, for example, result in decreased operation time as well as more accurate positioning. Due to the tortuosity of a given patient's native anatomy, the process of tracking a delivery system therethrough can often result in an undesirable rotation of the system. In some delivery procedures, the rotation of the delivery system can be especially important.
In some embodiments, a delivery system can include an indicator at a distal end of the delivery system that can allow confirmation of the correct orientation of the medical device (such as the correct orientation of a valve with respect to native leaflets) without first deploying the medical device. For example, the orientation of the medical device can be determined during tracking up to the aorta via a fluoroscopic view of the marker band. If the medical device is in an undesired orientation, the delivery system can be retracted and/or adjusted to a desired orientation.
In some embodiments, a delivery system for delivering a medical device through a vasculature can include a capsule for housing the medical device during delivery and a marker band rotatably fixed to the capsule. The marker band can include a band portion and a single indicator protruding from the band portion. The indicator can be configured to allow the rotational orientation of the marker band to be determined while the medical device is in the vasculature. The rotational orientation, can for example be relative to a central axis of the vasculature.
A method for determining a rotational orientation of a delivery system for a medical device through a vasculature can include providing a delivery system including a capsule and a marker band rotatably fixed to the capsule, the marker band including an indicator configured to allow rotational orientation of the marker band to be determined while the capsule is in the vasculature. The method can further include delivering the medical device through the vasculature and determining a rotational orientation of the marker band while the capsule is in the vasculature.
In some embodiments, a delivery system for delivering a medical device through a vasculature includes a capsule for housing the medical device during delivery and a marker band attached to a proximal end of the capsule. In some embodiments, the marker band is attached to a distal end or an intermediate portion of the capsule. The marker band can include a base portion and a protrusion that can be configured to extend from the base portion towards a distal end of the capsule. In some embodiments, the protrusion can protrude towards a proximal end of the capsule.
The accompanying figures, which are incorporated herein, form part of the specification and illustrate embodiments of relevant delivery systems and related methods. Together with the description, the figures further serve to explain the principles of and to enable a person skilled in the relevant art(s) to make and use the systems described herein.
The following detailed description refers to the accompanying figures which illustrate several embodiments. Other embodiments are possible. Modifications can be made to the embodiments described herein without departing from the spirit and scope of the present invention. Therefore, the following detailed description is not meant to be limiting.
Suitable medical devices for use in system 10 are not limited to prosthetic heart valves. In some embodiments, medical device 20 can be a device configured to be transported via a delivery catheter. In some embodiments, medical device 20 can be an expandable device, such as, for example, a percutaneously delivered device configured to be compacted and loaded onto a delivery catheter for advancement through a natural or artificial body lumen, such as for example through a patient's vasculature. In some embodiments, medical device 20 is not expandable. In some embodiments, medical device 20 is not designed to be implanted within the patient's body. For example, medical device 20 can be an embolic filter or a tool for retrieving an item from inside a patient.
In some embodiments, system 10 can be used in one or more percutaneous delivery procedures. For example, in some percutaneous procedures, a valve prosthesis can be compacted and loaded onto a delivery device, such as for example a catheter, for advancement through a patient's vasculature. System 10 can be configured for use in illiofemoral, apical, radial, direct aortic, and subclavian/axillary entry locations. System 10 can be configured to allow access from multiple locations per procedure (e.g. bilateral femoral access). In some embodiments, system 10 can be configured to deliver medical device 20 through an artery or vein, a femoral artery, a femoral vein, a jugular vein, a subclavian artery, an axillary artery, an aorta, an atrium, and/or a ventricle. System 10 can be configured to deliver medical device 20 via a transfemoral, transapical, transseptal, transatrial, transventrical, or transaortic procedure. In some embodiments, one or more components or portion of components of system 10 can be configured to flex to facilitate the traversal of system 10 through a body lumen during a delivery procedure. In some embodiments, one or more components of system 10 or portions thereof can include a curved outer surface and/or shape to facilitate movement through a curved body lumen.
As described above, in some embodiments, system 10 can be configured for use in a transfemoral delivery procedure. In one example of such a procedure, a delivery device including a prosthetic heart valve can be advanced in a retrograde manner through a patient's femoral artery and into the patient's descending aorta. A catheter can then be advanced under fluoroscopic guidance over the simulated aortic arch, through the ascending aorta, into the left ventricle, and mid-way across the defective aortic valve. Once positioning of the catheter is confirmed, the valve prosthesis can be deployed within the valve annulus. The valve prosthesis can then expand against the simulated annulus. In some embodiments, as the valve prosthesis is expanded, it can trap leaflets against the annulus, which can retain the native valve in a permanently open state.
As described above, in some embodiments, system 10 can be configured for use in a transapical delivery procedure. In one example of such a procedure, a trocar or overtube can be inserted into a patient's left ventricle through an incision created in the apex of the patient's heart. A dilator can be used to aid in the insertion of the trocar. In this approach, the native valve (for example, the mitral valve) can be approached downstream relative to blood flow. The trocar can be retracted sufficiently to release the self-expanding valve prosthesis. The dilator can be presented between the leaflets. The trocar can be rotated and adjusted to align the valve prosthesis in a desired alignment. The dilator can be advanced into the left atrium to begin disengaging the proximal section of the valve prosthesis from the dilator.
In some embodiments, system 10 can be configured for use in a transatrial delivery procedure. In one example of such a procedure, a dilator and trocar can be inserted through an incision made in the wall of the left atrium of the heart. The dilator and trocar can then be advanced through the native valve and into the left ventricle of the heart. The dilator can then be withdrawn from the trocar. A guide wire can be advanced through the trocar to the point where the valve prosthesis comes to the end of the trocar. The valve prosthesis can be advanced sufficiently to release a self-expanding valve prosthesis from the trocar. The trocar can be rotated and adjusted to align the valve prosthesis in a desired alignment. The trocar can be withdrawn completely from the heart such that the valve prosthesis self-expands into position and can assume the function of the native valve.
The few example procedures described above are not intended to be exhaustive. It is understood that not every act need be performed and additional acts can be included as would be apparent to one of ordinary skill in the art. In addition, the acts can be reordered as desired. Other medical devices and delivery techniques can be used with any of the parts described herein. It is further understood that the above delivery routes are merely exemplary and that other suitable delivery routes can be employed. The terms “delivery” and “delivery system” as used herein is intended to refer broadly to positioning a medical device at a desired location and related systems. Such terms do not necessitate a system that actually deposits a medical device at a site, such as for example a device that can be used to implant a prosthetic heart valve. The term “delivery system” can cover, for example, a system that temporarily positions a medical device at a desired location. For example, the delivery system can be used to position an embolic filter at a desired location within a patient's vasculature for a period of time before removing the embolic filter.
As described above, delivery system 10 can include dilator 18. In some embodiments, dilator 18 can be configured to dilate a tube, cavity, and/or opening in the body to facilitate introduction of system 10 for a delivery procedure. In some embodiments, dilator 18 can be configured to facilitate removal of system 10 following delivery of medical device 20.
Capsule 14 can be configured to house medical device 20 for delivery via system 10. For example, capsule 14 can include a lumen that is configured to receive the entirety of medical device 20 or a portion thereof. Capsule 14 can be in the form of a tube or another suitable shape. In some embodiments, capsule 14 can be in the form of a sheath. In some embodiments, a portion of capsule 14 can be tapered. For example, one or both of a proximal and a distal end of capsule 14 can be tapered. In some embodiments, capsule 14 can be a split sheath, such as one or more of the split sheath configurations described for example in U.S. Publication Appl. No. 2010/0100167, the disclosure of which is incorporated in its entirety by reference thereto.
Capsule 14 can include a marker band 24. Marker band 24 can, for example, be rotatably fixed to capsule 14. As described further herein, marker band 24 can include an indicator 30 that allows rotational orientation of the marker band to be determined while the medical device is in the vasculature. In some embodiments, an axial rotation of system 10 can additionally or alternatively be determined using marker band 24. For example, as shown in
Marker band 24 can, for example, be attached to a proximal end of capsule 14. When marker band 24 is positioned at a proximal end of capsule 14, the configuration can allow a user to determine when capsule 14 has been deployed far enough to get full release of medical device 20. Alternatively or additionally, marker band 24 can be positioned at a distal end of capsule 14. When marker band 24 is positioned at a distal end of capsule 14, the configuration can allow a user to know where the leading edge of capsule 14 is located. In some embodiments, marker band 24 can be positioned between a distal end and a proximal end of capsule 14.
As described above, due to the tortuosity of a given patient's native anatomy (such as within vasculature 12), the process of tracking delivery system 10 therethrough can often result in an undesirable rotation of medical device 20, capsule 14, and/or other components of system 10. In some delivery procedures, maintaining a desired rotation of these components can be especially important. A desired orientation of medical device 20 can be determined based on a number of factors. For example, in a tricuspid transcather aortic valve delivery procedure, it may be advantageous to deploy the valve with the same orientation as native leaflets. Further, when medical device 20 is in the form of a prosthetic heart valve, the following factors can be considered, alone or in combination, to verify that the valve is properly placed in an implantation site: (1) lack of paravalvular leakage around the replacement valve while blood is flowing through the valve; (2) orientation of the replacement valve relative to the coronary arteries; (3) the presence of coronary flow with the replacement valve in place; (4) longitudinal alignment of the replacement valve annulus with respect to the native patient anatomy; (5) verification that the position of the sinus region of the replacement valve does not interfere with native coronary flow; (6) verification that a sealing skirt is aligned with anatomical features to reduce and/or minimize paravalvular leakage; (7) verification that the replacement valve does not induce arrhythmias prior to final release; (8) verification that the replacement valve does not interfere with function of an adjacent valve, such as the mitral valve; (9) verification that engagement arms of the valve correspond to one or more sinus regions of the native anatomy; and (10) verification of desired rotational orientation for medical devices having asymmetrical profiles. By maintaining a desired rotation of medical device 20 relative to capsule 14 and/or other components of system 10, one or more of the above benefits can be achieved.
As shown for example in
In some embodiments, capsule 14 can be configured to move relative to medical device 20 to partially or fully release medical device 20 for delivery by system 10. In some embodiments, system 10 is configured to move capsule 14 relative to medical device 20 by moving capsule 14 from a first position to a second position while medical device 20 is relatively stationary. For example, in some embodiments, capsule 14 can be configured to move in a proximal direction relative to medical device 20 to partially or fully expose medical device 20 to allow for delivery medical device 20. In some embodiments, system 10 is configured to move capsule 14 relative to medical device 20 by moving medical device 20 from a first position to a second position while capsule 14 is relatively stationary. For example, medical device 20 can be pushed relative to capsule 14 in a distal direction to partially or fully expose medical device 20 for delivery in system 10. In some embodiments, movement of capsule 14 can be automatically or manually actuated.
Marker band 24 can include corners 32, 33, 34, and 35 between indicator 30 and band portion 28. These corners can be substantially rounded, for example with a fillet of approximately 0.02 inches. In some embodiments, one or all of corners 32, 33, 34, and 35 can be squared, chamfered, or another desired shape.
Marker band 24 can include a substantially smooth inner sidewall 36 and a substantially smooth outer sidewall 38. Marker band 24 can include a substantially flat first surface 40, a substantially flat second surface 42, and a substantially flat third surface 44. In some embodiments, the length from first surface 40 to second surface 42 can range from about 0.020 inches to about 0.030 inches. In some embodiments, the length from second surface 42 to third surface 44 can range from about 0.045 inches to about 0.060 inches. Suitable larger or smaller dimensions can be used.
In some embodiments, indicator 30 protrudes from band portion 28. The indicator can protrude from band portion 28 a distance ranging from about 1.0 mm to about 10 mm or longer. In some embodiments, indicator 30 can protrude a distance ranging from about 1.0 mm to about 4.3 mm.
A method for determining a rotational orientation of delivery system 10 for delivering medical device 20 through vasculature 12 can include providing delivery system 10 including capsule 14 and marker band 24 rotatably fixed to capsule 14. Marker band 24 can include indicator 30 configured to allow rotational orientation of marker band 24 to be determined while capsule 14 is in vasculature 12.
The method can further include delivering medical device 20 through vasculature 12 and determining a rotational orientation of marker band 24 while capsule 14 is in vasculature 12. The rotational orientation can be determined with respect to a central axis of vasculature 12. In some embodiments, the act of determining the rotational orientation of marker band 24 while medical device 20 is in vasculature 12 includes using a fluoroscope to view indicator 30 of marker band 24. In some embodiments, the method further includes adjusting the rotational orientation of marker band 24 in response to the determined rotational orientation.
As described further herein, other configurations for indicators may be suitable. Indicators can, for example, be in the form of suitable extensions, protrusions, asymmetrical feature, and/or cut-out pattern, which can provide the user a sense of directionality or orientation within the body. For example, an indicator can protrude from a band portion and can be in the form of a long and narrow protrusion. A marker band can include a plurality of asymmetrical indicators that can, for example, allow the rotational orientation of the marker band to be determined while the medical device is delivered through a vasculature.
For example,
Base portion 90 can be in the form of a ring, such as for example, a non-expandable solid ring. In some embodiments, base portion 90 can be configured to attach to capsule 84 of delivery system 80. Base portion 90 can be positioned at the distal end of capsule 84. Like other marker bands described herein, marker band 86 can include an indicator that allows a rotational orientation of marker band 86 to be determined while the medical device is in the vasculature. In some embodiments, one or more of protrusions 92 and 94 can be configured to function as such an indicator.
As described above, marker band 86 can include protrusions 92 and 94 that extend distally from the base portion. The protrusions can, for example, be in the form of narrow fingers that are laser cut into the marker band. Protrusions 92 and 94 can be configured to expand with the flare portion of the capsule. The protrusions can be the same or different lengths. In some embodiments, marker band 86 can include two sets of protrusions having two distinct lengths. For example, one set of protrusions 92 can correspond to the distal end of capsule 84 and another set of protrusions 94 can correspond to the distal end of medical device 88.
The choice of materials for the various valve prostheses described herein can be informed by the requirements of mechanical properties, temperature sensitivity, biocompatibility, moldability properties, or other factors apparent to a person having ordinary skill in the art. For example, one more of the parts (or a portion of one of the parts) can be made from suitable plastics, such as a suitable thermoplastic, suitable metals, and/or other suitable materials. One or more components or portions of components can be made of the same or similar material as any other component. One or more components or portions of components can be configured such that they are more flexible than another component or portion of a component. In some embodiments, one or more components can include radiopaque materials.
In some embodiments, one or more components can include additional and/or embedded structure configured to provide increased mechanical strength while allowing for increased flexibility. In some embodiments, one or more components, such as for example the capsule can include a metal laser cut tube, a wound coil, braid, or other suitable structure for increasing mechanical strength. The marker band can be made of 0.007 inch WT Ni-Ti flare tubing, for example.
In some embodiments, one or more components can be entirely or partially constructed using a single material or a composite material and/or a multi-layer material. In some embodiments, one or more of the components can include a material with a low coefficient of friction. For example, one or more portions of the systems, such as an exterior of a capsule can be coated with a biocompatible lubricant. In some embodiments, such a material can, for example, assist in the delivery system, delivering a medical device and/or withdrawing the system from a body lumen. In some embodiments, one or more components can include a multi-layer design, including for example one or more layers can be made entirely or partially of polymer. In some embodiments, one or more layers can be made entirely or partially of high-density polyethylene (HDPE). In some embodiments, one or more layers can be made entirely or partially of polytetrafluoroethylene (PTFE).
The foregoing description of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Other modifications and variations can be possible in light of the above teachings. The embodiments and examples were chosen and described in order to best explain the principles of the invention and its practical application and to thereby enable others skilled in the art to best utilize the invention in various embodiments with modifications as are suited to the particular use contemplated. It is intended that the appended claims be construed to include other alternative embodiments of the invention.
