The disclosure relates to a surgical perforation device, configured to deliver energy and an electrical current to a living tissue wherein the delivery of energy is controlled by change in electrical current properties. More specifically, the invention relates to a device and method for creating a perforation in the atrial septum or the parietal pericardium while using the change in electrical current properties as the device moves into the left atrium (in the case of puncturing the atrial septum) or the pericardial cavity (in the case of puncturing the parietal pericardium) to automatically stop the delivery of energy to the tissue being punctured upon completion of the puncture.
During the transseptal puncture procedure, there is a risk of inadvertent puncture of other tissues of the heart after the perforation has been created, resulting in general tissue damage within the left atrium, ancillary device damage (i.e., damage to pacemaker leads located in atrium) or potentially critical complications such as cardiac tamponade or inadvertent aortic puncture. A similar challenge is faced with procedures requiring access to the epicardium wherein accidental damage to the myocardium may occur if the puncture to the parietal pericardium is extended further than is desired. These problems could be addressed by a novel radiofrequency puncturing device wherein the delivery of radiofrequency energy is deactivated automatically after the puncture device has completed the perforation of the target tissue and entered the desired anatomical space (e.g. the left atrium or the pericardial cavity). As used herein, the parietal pericardium refers to the two outer layers of the pericardium, including both the fibrous pericardium as well as the parietal layer.
The disclosed device, system, and method could be used in other procedures. For example, the disclosed system and method could be used for TIPS procedures wherein the tissue being punctured is liver tissue between the inflow portal vein and the outflow hepatic vein of the liver, the anatomical space the device enters into after puncturing is the inflow portal vein, and the material (fluid or tissue) the device enters into after puncturing is blood. The delivery of radiofrequency energy is deactivated automatically after the puncture device has completed the perforation of the target tissue (liver tissue between the inflow portal vein and the outflow hepatic vein) and entered the desired anatomical space (the inflow portal vein).
Other examples wherein the disclosed and system may be used are listed below. In the following examples, the delivery of radiofrequency energy is deactivated automatically after the puncture device has completed the perforation of the target tissue and entered the desired anatomical space. In a Potts Shunt procedure, the tissue being punctured is tissue between the left pulmonary artery and the descending aorta, the anatomical space the device enters into after puncturing is descending aorta, and the material (fluid or tissue) the device enters into after puncturing is blood. For a procedure which includes accessing a blood vessel, the tissue being punctured is a blood vessel wall, the anatomical space the device enters into after puncturing is the blood vessel (or the target vessel), and the material (fluid or tissue) the device enters into after puncturing is blood. In a general procedure for creating a shunt, the tissue being punctured is material between two parts (or anatomical structures) of a body, the anatomical space the device enters into after puncturing is a destination anatomical structure, and the material (fluid or tissue) the device enters into after puncturing is material contained inside of the destination anatomical structure. For a procedure for Transcaval access in TAVR, the tissue being punctured is the tissue between the abdominal aorta and the adjacent inferior vena cava (IVC), the anatomical space the device enters into after puncturing is the abdominal aorta, and the material (fluid or tissue) the device enters into after puncturing is blood.
In a first broad aspect, embodiments of the present invention comprise a puncturing device for use with a generator which is capable of supplying energy for puncturing a tissue and an electrical current of known voltage, wherein the electrical current of known voltage can pass through the tissue without damaging the tissue. The puncturing device comprises an elongate member comprising a proximal portion and a distal portion; wherein the proximal portion is configured for being connected to the generator such that the energy for puncturing the tissue and the electrical current of known voltage are supplied to the elongate member. The distal portion ends in a distal tip, wherein the distal tip comprises an energy delivery device and two electrodes, wherein the energy delivery device is configured for delivering the energy for puncturing, and the two electrodes are configured for delivering the electrical current of a known voltage through a material which is in contact with the distal tip wherein a first of the two electrodes delivers the electrical current to the material and the electrical current returns to the puncturing device through a second of the two electrodes. In typical embodiments of the first broad aspect, the proximal portion of the elongate member comprises a hub through which the proximal portion is connected to the generator.
With some embodiments of the first broad aspect, the puncturing device further comprises a sensor which is capable of detecting a value of the electrical current between the two electrodes associated with the electrical current traveling through the material in contact with the distal tip, and the puncturing device has means to communicate to the generator the value which is associated with the electrical current between the two electrodes. With some other embodiments of the first broad aspect, the puncturing device further comprises means to communicate a first electrode current parameter and a second electrode current parameter to the generator.
As a feature of the first broad aspect, some embodiments comprise the sensor being configured to detect impedance. Some embodiments of the puncturing device comprise the sensor being configured to detect dielectricity. In some embodiments, the elongate member is a flexible wire. In some other embodiments, the elongate member is a needle.
In some embodiments of the first broad aspect, the two electrodes are located on a distal face of the puncture device. Typical embodiments further comprise an insulating material which electrically isolates the two electrodes from the energy delivery device. In some examples, the two electrodes are located laterally opposite to each other on a side of the distal tip.
In a second broad aspect, embodiments of the present invention include a system comprising a generator which is capable of supplying energy for puncturing a tissue and an electrical current of known voltage, wherein the electrical current of known voltage can pass through the tissue without damaging the tissue. The system also includes a puncturing device comprising an elongate member comprising a proximal portion and a distal portion. The proximal portion of the elongate member is configured for connecting to the generator such that the energy for puncturing the tissue and the electrical current of a known voltage are supplied to the elongate member. The distal portion of the elongate member ends in a distal tip, wherein the distal tip comprises an energy delivery device which is configured for delivering the energy for puncturing and two electrodes are configured for delivering the electrical current of known voltage through a material which is in contact with the distal tip, wherein a first of the two electrodes delivers the electrical current to the material and the electrical current returns to the puncturing device through a second of the two electrodes. The system further includes a sensor which is capable of detecting a value of the electrical current between the two electrodes associated with the electrical current traveling through the material in contact with the distal tip. The generator comprises a generator switch for disabling the supplying of the energy for puncturing to the energy delivery device of the distal tip based on the value of the electric current detected by the sensor. In typical embodiments of the second broad aspect, the proximal portion of the elongate member comprises a hub through which the proximal portion is connected to the generator.
In some embodiments of the second broad aspect, the puncturing device comprises a sensor which is capable of detecting a value of the electrical current between the two electrodes associated with the electrical current traveling through the material in contact with the distal tip, and the puncturing device has means to communicate to the generator switch the value which is associated with the electrical current between the two electrodes. In some other embodiments of the second broad aspect, the generator includes the sensor and the puncturing device comprises means to communicate to the sensor a first electrode current parameter and a second electrode current parameter.
As a feature of the second broad aspect, in some embodiments, the generator switch is a hardware switch. In some other embodiments, the generator switch is a software algorithm. Typical embodiments of the second broad aspect include the generator delivering energy for puncturing the tissue in pulses and the electrical current of known voltage is delivered to the two electrodes between pulses of energy for puncturing.
In some embodiments of the second broad aspect, the generator switch disables the delivery of energy for puncturing when the value detected by the sensor is a value associated with blood. In some other embodiments, the generator switch disables the delivery of energy for puncturing when the value detected by the sensor is less than a threshold value, and the threshold value is between a value associated with blood and a value associated with the tissue.
In a third broad aspect, embodiments of the present invention are for a method of accessing the left atrium which comprises the steps of: (i) gaining access to the vasculature through the groin to the femoral vein; (ii) inserting a guidewire into the femoral vein; (iii) advancing the guidewire up the inferior vena cava to the right atrium and into the superior vena cava; (iv) using the guidewire as a guide rail, advancing an assembly of a puncturing device, a dilator, and a sheath, wherein the puncturing device comprises a needle, and removing the guidewire; (v) with a distal tip of the puncturing device slightly protruding from a distal tip of the dilator and the sheath, maneuvering the assembly such that the distal tip of the puncturing device is located on the fossa ovalis of the septum wherein an energy delivery device and two electrodes on the distal tip of the puncturing device contact a tissue of the fossa ovalis; (vi) turning on a generator and delivering pulses of energy for puncturing tissue through the energy delivery device to the tissue of the fossa ovalis; (vii) between the pulses of energy of step (vi), delivering an electrical current of known voltage between the two electrodes at the distal tip of the puncturing device via the tissue of the fossa ovalis wherein the electrical current exits the puncturing device through a first of two electrodes and returns to the puncturing through a second of the two electrodes; (viii) upon completing the puncture, advancing the puncture device from the right atrium to the left atrium whereby the distal tip of the puncturing device is no longer in contact with the tissue of the fossa ovalis and there is a change in value of an electrical property of the electrical current between the electrodes at the distal tip of the puncturing device wherein the change in the electrical property indicates the distal tip of the puncturing device is no longer in contact with the tissue of the fossa ovalis; (ix) detecting the change in value of the electrical property via a sensor and stopping the delivery of energy for puncturing tissue by the generator.
As a feature of the third broad aspect, typical embodiments include the electrical property being impedance or dielectricity. Some embodiments of the method further comprise the step (x) of advancing the dilator and the sheath over the puncturing device into the left atrium, removing the dilator and the puncturing device, and delivering an ancillary device through the sheath into the left atrium.
In a fourth broad aspect, embodiments of the present invention are for a method of accessing the left atrium comprises the steps of: (i) gaining access to the vasculature through the groin to the femoral vein; (ii) inserting the puncturing device into the femoral vein wherein the puncturing device comprises a flexible wire; (iii) advancing the puncturing device up the inferior vena cava to the right atrium and into the superior vena cava; (iv) using the puncturing device as a guide rail, advancing an assembly of a dilator and a sheath; (v) with a distal tip of the puncturing device slightly protruding from a distal tip of the dilator and the sheath, maneuvering the assembly such that the distal tip of the puncturing device is located on the fossa ovalis of the septum wherein an energy delivery device and two electrodes on the distal tip of the puncturing device contact a tissue of the fossa ovalis; (vi) turning on a generator and delivering pulses of energy for puncturing tissue through the energy delivery device to the tissue of the fossa ovalis; (vii) between the pulses of energy of step (vi), delivering an electrical current of known voltage between the two electrodes at the distal tip of the puncturing device via the tissue of the fossa ovalis wherein the electrical current exits the puncturing device through a first of two electrodes and returns to the puncturing through a second of the two electrodes; (viii) upon completing the puncture, advancing the puncture device from the right atrium to the left atrium whereby the distal tip of the puncturing device is no longer in contact with the tissue of the fossa ovalis and there is a change in value of an electrical property of the electrical current between the electrodes at the distal tip of the puncturing device wherein the change in the electrical property indicates the distal tip of the puncturing device is no longer in contact with the tissue of the fossa ovalis; (ix) detecting the change in value of the electrical property via a sensor and stopping the delivery of energy for puncturing tissue by the generator. For typical embodiments, the electrical property is impedance or dielectricity.
Some embodiments of the fourth broad aspect further comprise the step (x) of advancing the dilator and the sheath over the puncturing device into the left atrium, removing the dilator and the puncturing device, and delivering an ancillary device through the sheath into the left atrium.
In order that the invention may be readily understood, embodiments of the invention are illustrated by way of examples in the accompanying drawings.
Certain medical procedures require the use of a medical device that can create punctures or channels through tissues. Specifically, puncturing the septum of a heart creates a direct route to the left atrium where numerous cardiology procedures take place. One such device that gains access to the left atrium is a transseptal puncturing device which, in some devices, delivers radiofrequency energy from a generator into the tissue to create the perforation. The user positions the puncturing device at a target location on the fossa ovalis located on the septum of the heart and turns on the generator to begin delivering energy to the target location. The delivery of radiofrequency energy to a tissue results in vaporization of the intracellular fluid of the cells which are in contact with the energy delivery device. Ultimately, this results in a void, hole, or channel at the target tissue site.
During the transseptal puncture procedure, there is a risk of inadvertent puncture of other tissues of the heart after the perforation of the septum has been created, resulting in general tissue damage within the left atrium, ancillary device damage (i.e., damage to pacemaker leads located in atrium) or potentially critical complications such as cardiac tamponade or inadvertent aortic puncture. A cardiac tamponade is a life-threatening complication of transseptal punctures which occurs when a perforation is created at the left atrial wall, left atrial roof, or left atrial appendage. This perforation of the atrial wall leads to an accumulation of fluid within the pericardial cavity around your heart. This buildup of fluid compresses your heart which in turn reduces the amount of blood able to enter your heart. An inadvertent aortic puncture is a rare life-threatening complication where the puncturing device enters and punctures the aorta which may require surgical repair.
A similar challenge is faced with procedures requiring access to the epicardium wherein accidental damage to the myocardium may occur if the puncture to the parietal pericardium is extended further than is desired. In such procedures damage to the myocardium can be prevented by the delivery of radiofrequency energy being stopped after the puncture device has entered the pericardial cavity.
In light of these complications associated with inadvertent puncturing, the present inventors have conceived of and reduced to practice embodiments of an electrosurgical device wherein the delivery of radiofrequency energy is deactivated automatically after the puncture device has completed the perforation and entered the left atrium or pericardial cavity. In some cases, a radiofrequency (RF) energy source is used to selectively apply RF energy to tissue. Typical embodiments of the device include insulation to protect the user and the patient, and are configured to avoid creating emboli.
With specific reference now to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of embodiments of the present invention only. In this regard, no attempt is made to show structural details of the invention in more detail than is necessary for a fundamental understanding of the invention. The description taken with the drawings will make apparent to those skilled in the art how the several aspects of the invention may be embodied in practice.
Before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments or of being practiced or carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein is for the purpose of description and should not be regarded as limiting.
As used herein, the terms ‘proximal’ and ‘distal’ are defined with respect to the user. That is, the term ‘proximal’ refers to a part or portion closer to the user, and the term ‘distal’ refers to a part or portion further away from the user when the device is in use. Also, it should be noted that while, for clarity of explanation, the term tubular or tubular member is used to describe the members that enclose the disclosed medical devices, the term tubular member is intended to describe both circular and non-circular embodiments of the enclosing member. The term tubular member is used in this disclosure to describe dilators, sheaths, and other members that define a lumen for containing a medical device.
Referring to
The force transmitting portion 114 defines a force transmitting portion length, the force transmitting portion length being larger than the distal portion length. In some embodiments of the invention, the force transmitting portion 114 has a force transmitting portion flexural rigidity of at least about 0.016 Nm2, for example about 0.017 Nm2. The force transmitting portion 114 has a force transmitting portion flexural rigidity allowing the transmission to the handle 110 of contact forces exerted on the distal portion 112 when the distal portion 112 contacts the target location to provide tactile feedback to the intended user. In addition, the force transmitting portion flexural rigidity allows for the transmission of force from the handle 110 to the distal portion 112 in order to, for example, advance the distal portion 112 within the body of the patient or to orient the distal portion 112 by applying torque to the handle 110.
Therefore, the proposed medical device 100 is structured such that it provides the intended user with a similar, or better, ‘feel’ as some prior art devices. That is, although the structure and function of the medical device 100 differs significantly from prior art devices.
In some embodiments of the invention, the distal portion 112 has a distal portion flexural rigidity of at least about 0.0019 Nm2, for example 0.0021 Nm2. Such values of flexural rigidity enhance the cognitive ergonomics of the proposed medical device 100 by providing tactile feedback to the intended user and allowing for the transmission of radial (torque) and longitudinal forces from the handle to the distal portion.
In typical embodiments of the invention, the medical device 100 includes an electrically conductive elongate member 102 having an electrical insulation 104 disposed thereon. The electrical insulation 104 substantially covers the entire outer surface of the elongate member 102 such that elongate member 102 is able to deliver energy from its proximal region to the electrode 106 at its distal region, without substantial leakage of energy along the length of the elongate member 102. The elongate member 102 defines a lumen 208 and at least one side-port 600 (shown, for example, in
The one or more side-ports 600 are particularly useful in typical embodiments of medical device 100 wherein a lumen 208 of the elongate member 102 is not open to the surrounding environment via the distal end of the medical device 100 (i.e. wherein medical device 100 is a close-ended device), for example, in the embodiments of
In embodiments comprising side-port(s) 600, the side-port(s) 600 allow for fluids to be injected into the surrounding environment from the lumen 208, and/or allow for pressure to be measured by providing a pressure transmitting lumen through medical device 100. In some examples, the side-port(s) 600 are formed radially through elongate member 102 and electrical insulation 104, thereby allowing for fluid communication between the surrounding environment and the lumen 208. In alternative embodiments, a side-port 600 is formed radially through a portion of the electrode 106.
The size and shape of the side-port(s) 600 may vary depending on the intended application of the medical device 100, and the invention is not limited in this regard. For example, in one embodiment, the side-port(s) 600 is between about 0.25 mm and about 0.45 mm in diameter. Some embodiments include side-ports of more than one size. In addition, the number of side-ports 600 may vary, and they may be located anywhere along the medical device 100 that does not interfere with the functioning of the device. For example, as shown in
When a medical device that relies on side-ports to provide fluid communication between its lumen and the surrounding environment is inside a lumen of a close-fitting member, the side-ports may be partially or completely occluded or blocked. The embodiments of
Tubular member 800 may comprise a dilator, a sheath, or some other member defining a lumen configured to receive a medical device 100.
Referring to
In the embodiment of
In the embodiment of
In the embodiment of
The side-port(s) 600 and the device lumen 809 together provide a pressure transmitting lumen. The pressure transmitting lumen is operable to be coupled to a pressure transducer, for example, external pressure transducer 708 (to be described with respect to
Distal tip 403 of medical device 100 is shown in the example of
Typical embodiments of medical device 100 comprise a conductive member (elongate member 102, or main member 210 joined to end member 212), which is typically comprised of a metallic material. The conductive member is in electrical communication with distal electrode 106, and a layer of insulation (electrical insulation 104) covers the metallic material. In other words, the elongate member 102 comprises an electrically conductive material, and a layer of insulation covers the electrically conductive material, the electrically conductive material being electrically coupled to the electrode 106. For some single piece embodiments, elongate member 102 has an on outer diameter proximal of change in diameter 831 of about 0.7 mm to about 0.8 mm at distal end 206, and an outer diameter for reduced diameter distal portion 830 of about 0.4 mm to about 0.62 mm. For some two piece embodiments, end member 212 has an outer diameter proximal of change in diameter 831 of about 0.40 mm to about 0.80 mm, and an outer diameter for distal portion 830 of about 0.22 mm to about 0.62 mm. The above described embodiments are typically used with a tubular member defining a corresponding lumen about 0.01 mm (0.0005 inches) to about 0.04 mm (0.0015 inches) larger than the outer diameter of medical device 100 proximal of change in diameter 831.
In the embodiment of
Making reference again to
Some embodiments of electrode 106 typically create a puncture in tissue with a diameter 10 to 20 percent larger than the electrode. Such a puncture diameter is typically large enough to facilitate passage of the part of medical device proximal of change of diameter 831 (i.e. the larger diameter portion of medical device) through the tissue puncture, and to start advancing a dilator over medical device 100 and through the tissue.
The embodiment of conduit 808 in
The embodiment of
The embodiment of
One embodiment is a dilator comprising a tubular member defining a lumen in fluid communication with a distal end aperture, a proximal region having a first inner diameter, and a distal region having an increased diameter portion. The increased diameter portion extends proximally from a distal end of the dilator and defines a substantially longitudinally constant second inner diameter that is greater than the first inner diameter.
The embodiment of
The apparatus of
Some embodiments of the medical device and the tubular member further comprise corresponding markers for aligning the side-port of the medical device within the tubular member lumen to form said conduit. In the example of
In some embodiments of the kit, the corresponding markers are configured for rotationally aligning the side-port within the tubular member lumen. In the example of
An embodiment of a kit comprises a tubular member defining a tubular member lumen in fluid communication with a distal end aperture, and a medical device having a closed distal end. The medical device comprises a device lumen in fluid communication with at least one side-port, and a distal portion extending from the at least one side-port to a distal end of the medical device. Medical device and tubular member are configured to cooperatively form a conduit between an outer surface of the distal portion and an inner surface of the tubular member when the medical device is inserted within the tubular member lumen. The conduit extends at least between the side-port and the distal end aperture for enabling fluid communication between the side-port and an environment external to the distal end aperture.
In a specific embodiment of a kit, end member 212 has an on outer diameter proximal of change in diameter 831 of about 0.032 inches (about 0.81 mm), and an outer diameter at reduced diameter distal portion 830 of about 0.020 inches (about 0.51 mm) to about 0.025 inches (about 0.64 mm). End member 212 is used with a tubular member defining a lumen about 0.0325 inches (0.82 mm) to about 0.0335 inches (0.85 mm).
Referring to
Referring to
The external pressure transducer 708 produces a signal that varies as a function of the pressure it senses. The external pressure transducer 708 is electrically coupled to a pressure monitoring system 710 that is operative to convert the signal provided by the transducer 708 and display, for example, a pressure contour as a function of time. Thus, pressure is optionally measured and/or recorded and, in accordance with one embodiment of a method aspect as described further herein below, used to determine a position of the distal region 202. In those embodiments of the medical device 100 that do not comprise a lumen in fluid communication with the outside environment, a pressure transducer may be mounted at or proximate to the distal portion 112 of the medical device 100 and coupled to a pressure monitoring system, for example, via an electrical connection.
As previously mentioned, for some embodiments the medical device 100 is operatively coupled to a source of fluid 712 for delivering various fluids to the medical device 100 and thereby to a surrounding environment. The source of fluid 712 may be, for example, an IV bag or a syringe. The source of fluid 712 may be operatively coupled to the lumen 208 via the tubing 508 and the adapter 704, as mentioned herein above. Alternatively, or in addition, some embodiments include the medical device 100 being operatively coupled to an aspiration device for removing material from the patient's body through one or more of the side-ports 600.
In one broad aspect, the medical apparatus is used in a method of establishing a conduit for fluid communication for a medical device 100, the medical device defining a device lumen 809 in fluid communication with a side-port 600. Making reference to
In some embodiments of the broad aspect, the medical device comprises a medical device proximal marker 810 proximal of the side-port, and a medical device distal marker 812 distal of the side-port, and step (b) includes visualizing at least one of the proximal marker and the distal marker to position the medical device. In some such embodiments, step (b) comprises positioning side-port 600 within tubular member lumen 802, for example, by using a medical device proximal marker 810 and a medical device distal marker 812. In such embodiments of the method, it is not necessary for distal tip 403 to be inside of tubular member lumen 802. In some embodiments of the method, the medical device further comprises a side-port marker wherein the side-port marker and the side-port are equidistant from a tip of the medical device, and wherein step (b) includes visualizing the side-port marker to position the medical device. In some other embodiments, step (b) comprises positioning distal portion 830 of distal portion 112 within tubular member lumen 802, which inherently positions the side-port in the tubular member lumen. In some embodiments of the method, step (b) includes aligning a distal tip 403 of the medical device with the tubular member distal end 801.
Some embodiments of the broad aspect further comprise a step (c) of delivering fluid through the side-port 600, wherein the fluid is a contrast fluid 814 and wherein step (c) includes delivering the contrast fluid distally through the distal end of the tubular member. Some such embodiments further comprise a step of delivering electrical energy to puncture tissue before the contrast fluid is delivered. Some embodiments comprise a step (d) of delivering electrical energy through the medical device to create a puncture through a tissue after the contrast fluid is delivered.
In some embodiments, the tissue comprises a septum of a heart, and step (c) comprises staining the septum by delivering contrast fluid through the side-port.
In some embodiments of the broad aspect, the side-port 600 and the device lumen 809 together comprise a pressure transmitting lumen, and the method further comprises a step (c) of measuring a pressure of an environment external to the distal end using the side-port and the conduit. Some such embodiments further comprise a step (d) of delivering fluid through the side-port.
Some embodiments of the broad aspect further comprise a step (c) of withdrawing fluid through the side-port 600. In some such embodiments, the fluid is blood.
In one example of a method of use, illustrated in
The example of the method includes a user advancing sheath 820 and a dilator (i.e. tubular member 800) through inferior vena cava 824, and introducing the sheath and tubular member 800 into the right atrium 826 of the heart. An electrosurgical device, for example medical device 100 described herein above, is then introduced into tubular member lumen 802, and advanced toward the heart. In typical embodiments of the method, these steps are performed with the aid of fluoroscopic imaging.
After inserting medical device 100 into tubular member 800, the user positions the distal end of tubular member 800 against the atrial septum 822 (
Once medical device 100 and tubular member 800 have been positioned, additional steps can be performed, including taking a pressure measurement and/or delivering material to the target site, for example, a contrast agent, through side-port(s) 600. The
Starting from the position illustrated by the
Referring now to
The elongate member 102 is typically sized such that the handle 110 remains outside of the patient when the distal end 206 is within the body, for example, adjacent the target site. That is, the proximal end 204 is at a location outside of the body, while the distal end 206 is located within the heart of the patient. Thus, in some embodiments of the invention, the length of the elongate member 102, i.e., the sum of the force transmitting length and the distal portion length, is between about 30 cm and about 100 cm, depending, for example, on the specific application and/or target site.
The transverse cross-sectional shape of the elongate member 102 may take any suitable configuration, and the invention is not limited in this regard. For example, the transverse cross-sectional shape of the elongate member 102 is substantially circular, ovoid, oblong, or polygonal, among other possibilities. Furthermore, in some embodiments, the cross-sectional shape varies along the length of the elongate member 102. For example, in one embodiment, the cross-sectional shape of the proximal region 200 is substantially circular, while the cross-sectional shape of the distal region 202 is substantially ovoid.
In typical embodiments, the outer diameter of the elongate member 102 is sized such that it fits within vessels of the patient's body. For example, in some embodiments, the outer diameter of the elongate member 102 is between about 0.40 mm and about 1.5 mm (i.e. between about 27 Gauge and about 17 Gauge). In some embodiments, the outer diameter of the elongate member 102 varies along the length of the elongate member 102. For example, in some embodiments, the outer diameter of the elongate member 102 tapers from the proximal end 204 towards the distal end 206. In one specific embodiment, the outer diameter of the proximal region 200 of the elongate member 102 is about 1.5 mm. In this embodiment, at a point about 4 cm from the distal end 206, the outer diameter begins to decrease such that the distal end 206 of the elongate member 102 is about 0.7 mm in outer diameter. In a further embodiment, the outer diameter of the elongate member 102 tapers from about 1.3 mm to about 0.8 mm at a distance of about 1.5 mm from the distal end 206.
In a further embodiment, the elongate member 102 is manufactured from two pieces of material, each having a different diameter, which are joined together. For example, as shown in
In embodiments of the invention wherein the elongate member 102 defines a lumen 208, the wall thickness of the elongate member 102 may vary depending on the application, and the invention is not limited in this regard. For example, if a stiffer device is desirable, the wall thickness is typically greater than if more flexibility is desired. In some embodiments, the wall thickness in the force transmitting region is from about 0.05 mm to about 0.40 mm, and remains constant along the length of the elongate member 102. In other embodiments, wherein the elongate member 102 is tapered, the wall thickness of the elongate member 102 varies along the elongate member 102. For example, in some embodiments, the wall thickness in the proximal region 200 is from about 0.1 mm to about 0.4 mm, tapering to a thickness of from about 0.05 mm to about 0.20 mm in the distal region 202. In some embodiments, the wall tapers from inside to outside, thereby maintaining a consistent outer diameter and having a changing inner diameter. Alternative embodiments include the wall tapering from outside to inside, thereby maintaining a consistent inner diameter and having a changing outer diameter. Further alternative embodiments include the wall of the elongate member 102 tapering from both the inside and the outside, for example, by having both diameters decrease such that the wall thickness remains constant. For example, in some embodiments the lumen 208 has a diameter of from about 0.4 mm to about 0.8 mm at the proximal region 200, and tapers to a diameter of from about 0.3 mm to about 0.5 mm at the distal region 202. In other alternative embodiments, the outer diameter decreases while the inner diameter increases, such that the wall tapers from both the inside and the outside.
In some embodiments, the elongate member 102, and therefore the medical device 100, are curved or bent, as shown in
The curved section 300 may be applied to the elongate member 102 by a variety of methods. For example, in one embodiment, the elongate member 102 is manufactured in a curved mold. In another embodiment, the elongate member 102 is manufactured in a substantially straight shape then placed in a heated mold to force the elongate member 102 to adopt a curved shape. Alternatively, the elongate member 102 is manufactured in a substantially straight shape and is forcibly bent by gripping the elongate member 102 just proximal to the region to be curved and applying force to curve the distal region 202. In an alternative embodiment, the elongate member 102 includes a main member 210 and an end member 212, as described with respect to
As mentioned herein above, in some embodiments the proximal region 200 of the elongate member 102 is structured to be coupled to an energy source. To facilitate this coupling, the proximal region 200 may comprise a hub 108 that allows for the energy source to be electrically connected to the elongate member 102. Further details regarding the hub 108 are described herein below. In other embodiments, the proximal region 200 is coupled to an energy source by other methods known to those of skill in the art, and the invention is not limited in this regard.
In typical embodiments, the elongate member 102 is made from an electrically conductive material that is biocompatible. As used herein, ‘biocompatible’ refers to a material that is suitable for use within the body during the course of a surgical procedure. Such materials include stainless steels, copper, titanium and nickel-titanium alloys (for example, NITINOL®), amongst others. Furthermore, in some embodiments, different regions of the elongate member 102 are made from different materials. In an example of the embodiment of
As mentioned herein above, an electrical insulation 104 is disposed on at least a portion of the outer surface of the elongate member 102. In some embodiments, for example as shown in
In embodiments as illustrated in
The electrical insulation 104 may be one of many biocompatible dielectric materials, including but not limited to, polytetrafluoroethylene (PTFE, Teflon®), parylene, polyimides, polyethylene terepthalate (PET), polyether block amide (PEBAX®), and polyetheretherketone (PEEK™), as well as combinations thereof. The thickness of the electrical insulation 104 may vary depending on the material used. Typically, the thickness of the electrical insulation 104 is from about 0.02 mm to about 0.12 mm.
In some embodiments, the electrical insulation 104 comprises a plurality of dielectric materials. This is useful, for example, in cases where different properties are required for different portions of the electrical insulation 104. In certain applications, for example, substantial heat is generated at the electrode 106. In such applications, a material with a sufficiently high melting point is required for the distal-most portion of the electrical insulation 104, so that this portion of the electrical insulation 104, located adjacent to electrode 106, doesn't melt. Furthermore, in some embodiments, a material with a high dielectric strength is desired for all of, or a portion of, the electrical insulation 104. In some particular embodiments, electrical insulation 104 has a combination of both of the aforementioned features.
With reference now to
In further embodiments as shown in
The electrical insulation 104 may be applied to the elongate member 102 by a variety of methods. For example, if the electrical insulation 104 includes PTFE, it may be provided in the form of heat-shrink tubing, which is placed over the elongate member 102 and subjected to heat to substantially tighten around the elongate member 102. If the electrically insulating material is parylene, for example, it may be applied to the elongate member 102 by vapor deposition. In other embodiments, depending on the specific material used, the electrical insulation 104 may be applied to the elongate member 102 using alternate methods such as dip-coating, co-extrusion, or spraying.
As mentioned herein above, in embodiments of the present invention the elongate member 102 comprises an electrode 106 at the distal region, the electrode 106 configured to create a channel via radiofrequency perforation. As used herein, ‘radiofrequency perforation’ refers to a procedure in which radiofrequency (RF) electrical energy is applied from a device to a tissue to create a perforation or fenestration through the tissue. Without being limited to a particular theory of operation, it is believed that the RF energy serves to rapidly increase tissue temperature to the extent that water in the intracellular fluid converts to steam, inducing cell lysis as a result of elevated pressure within the cell. Furthermore, electrical breakdown may occur within the cell, wherein the electric field induced by the alternating current exceeds the dielectric strength of the medium located between the radiofrequency perforator and the cell, causing a dielectric breakdown. In addition, mechanical breakdown may occur, wherein alternating current induces stresses on polar molecules in the cell. Upon the occurrence of cell lysis and rupture, a void is created, allowing the device to advance into the tissue with little resistance. In order to increase the current density delivered to the tissue and achieve this effect, the device from which energy is applied, i.e. the electrode, is relatively small, having an electrically exposed surface area of no greater than about 15 mm2. In addition, the energy source is capable of applying a high voltage through a high impedance load, as will be discussed further herein below. This is in contrast to RF ablation, whereby a larger-tipped device is utilized to deliver RF energy to a larger region in order to slowly desiccate the tissue. As opposed to RF perforation, which creates a void in the tissue through which the device is advanced, the objective of RF ablation is to create a large, non-penetrating lesion in the tissue, in order to disrupt electrical conduction. Thus, for the purposes of the present invention, the electrode refers to a device which is electrically conductive and exposed, having an exposed surface area of no greater than about 15 mm2, and which is operable to delivery energy to create a perforation or fenestration through tissue when coupled to a suitable energy source and positioned at a target site. The perforation is created, for example, by vaporizing intracellular fluid of cells with which it is in contact, such that a void, hole, or channel is created in the tissue located at the target site.
In further embodiments, as shown in
It is a common belief that it is necessary to have a distal opening in order to properly deliver a contrast agent to a target site. However, it was unpredictably found that it is possible to properly operate the medical device 100 in the absence of distal openings. Advantageously, these embodiments reduce the risk that a core of tissue becomes stuck in such a distal opening when creating the channel through the tissue. Avoiding such tissue cores is desirable as they may enter the blood circulation, which creates risks of blocking blood vessels, leading to potentially lethal infarctions.
Thus, as shown in
In other embodiments as shown, for example, in
The external component 400 may take a variety of shapes, for example, cylindrical, main, conical, or truncated conical. The distal end of the external component 400 may also have different configuration, for example, rounded, or flat. Furthermore, some embodiments of the external component 400 are made from biocompatible electrically conductive materials, for example, stainless steel. The external component 400 may be coupled to the elongate member 102 by a variety of methods. In one embodiment, external component 400 is welded to the elongate member 102. In another embodiment, external component 400 is soldered to the elongate member 102. In one such embodiment, the solder material itself comprises the external component 400, e.g., an amount of solder is electrically coupled to the elongate member 102 in order to function as at least a portion of the electrode 106. In further embodiments, other methods of coupling the external component 400 to the elongate member 102 are used, and the invention is not limited in this regard.
In these embodiments, as described herein above, the electrically exposed and conductive surface area of the electrode 106 is no greater than about 15 mm2. In embodiments wherein the electrical insulation 104 covers a portion of the external component 400, the portion of the external component 400 that is covered by the electrical insulation 104 is not included when determining the surface area of the electrode 106.
Referring again to
In some embodiments, the distal tip 403 is substantially bullet-shaped, as shown in FIG. 2E, which allows the intended user to drag the distal tip 403 across the surface of tissues in the patient's body and to catch on to tissues at the target site. For example, if the target site includes a fossa ovalis, as described further herein below, the bullet-shaped tip may catch on to the fossa ovalis so that longitudinal force applied at a proximal portion of medical device 100 causes the electrode 106 to advance into and through the fossa ovalis rather than slipping out of the fossa ovalis. Because of the tactile feedback provided by the medical device 100, this operation facilitates positioning of the medical device 100 prior to energy delivery to create a channel.
As mentioned herein above, in some embodiments, the medical device 100 comprises a hub 108 coupled to the proximal region. In some embodiments, the hub 108 is part of the handle 110 of the medical device 100, and facilitates the connection of the elongate member 102 to an energy source and a fluid source, for example, a contrast fluid source.
In the embodiment illustrated in
In some embodiments, medical device 100 is a transseptal puncturing device comprising an elongate member which is electrically conductive, an electrical connector in electrical communication with the elongate member, and an electrode at a distal end of the electrically conductive elongate member for delivering energy to tissue. A method of using the transseptal puncturing device comprises the steps of (1) connecting an electrically conductive component, which is in electrical communication with a source of energy, to the electrical connector, and (2) delivering electrical energy through the electrode to a tissue. The electrically conductive component may comprise a plug, such as plug 504, and a wire connected thereto. Some embodiments of the method further comprise a step (3) of disconnecting the electrically conductive component from the electrical connector. In such embodiments, the electrically conductive component is connected in a releasable manner.
In some embodiments, the hub 108 is structured to be operatively coupled to a fluid connector 506, for example a Luer lock, which is connected to tubing 508. Tubing 508 is structured to be operatively coupled at one end to an aspirating device, a source of fluid 712 (for example a syringe), or a pressure sensing device (for example a pressure transducer 708). The other end of tubing 508 may be operatively coupled to the fluid connector 506, such that tubing 508 and lumen 208 are in fluid communication with each other, thus allowing for a flow of fluid between an external device and the lumen 208. In embodiments in which a hub 108 is part of handle 110, fluid and/or electrical connections do not have to be made only with the hub 108 i.e. connections may be made with other parts of the handle 110, or with parts of medical device 100 other than the handle.
In some embodiments, the hub 108 further comprises one or more curve-direction or orientation indicators 510 that are located on one side of the hub 108 to indicate the direction of the curved section 300. The orientation indicator(s) 510 may comprise inks, etching, or other materials that enhance visualization or tactile sensation.
In some embodiments of the invention, the handle 110 includes a relatively large, graspable surface so that tactile feedback can be transmitted relatively efficiently, for example by transmitting vibrations. In some embodiments of the invention, the handle 110 includes ridges 512, for example, in the hub 108, which enhance this tactile feedback. The ridges 512 allow the intended user to fully grasp the handle 110 without holding the handle 110 tightly, which facilitates the transmission of this feedback.
In some embodiments of the invention, the medical device 100, as shown in
Also, in some embodiments of the invention that include the curved section 300, the curved section 300 defines a center of curvature (not shown in the drawings), and the side-port(s) 600 extend from the lumen 208 substantially towards the center of curvature. This configuration substantially prevents the edges of the side-port(s) 600 from catching onto tissues as the tissues are perforated. However, in alternative embodiments of the invention, the side-port(s) 600 extend in any other suitable orientation.
In some embodiments, one or more radiopaque markers 714 (as shown in
In some embodiments, the shape of the medical device 100 may be modifiable. For example, in some applications, it is desired that medical device 100 be capable of changing between a straight configuration, for example as shown in
In some embodiments, the medical device 100 includes at least one further electrically conductive component, located proximal to the electrode 106. For example, the electrically conductive component may be a metal ring positioned on or around the electrical insulation 104 which has a sufficiently large surface area to be operable as a return electrode. In such an embodiment, the medical device 100 may function in a bipolar manner, whereby electrical energy flows from the electrode 106, through tissue at the target site, to the at least one further electrically conductive component. Furthermore, in such embodiments, the medical device 100 includes at least one electrical conductor, for example a wire, for conducting electrical energy from the at least one further conductive component to a current sink, for example, circuit ground.
In some embodiments, medical device 100 is used in conjunction with a source of radiofrequency energy suitable for perforating material within a patient's body. The source of energy may be a radiofrequency (RF) electrical generator 700, operable in the range of about 100 kHz to about 1000 kHz, and designed to generate a high voltage over a short period of time. More specifically, in some embodiments, the voltage generated by the generator increases from about 0 V (peak-to-peak) to greater than about 75 V (peak-to-peak) in less than about 0.6 seconds. The maximum voltage generated by generator 700 may be between about 180V peak-to-peak and about 3000V peak-to-peak. The waveform generated may vary, and may include, for example, a sine-wave, a rectangular-wave, or a pulsed rectangular wave, amongst others. During delivery of radiofrequency energy, the impedance load may increase due to occurrences such as tissue lesioning near the target-site, or the formation of a vapor layer following cell rupture. In some embodiments, the generator 700 is operable to continue to increase the voltage, even as the impedance load increases. For example, energy may be delivered to a tissue within a body at a voltage that rapidly increases from about 0 V (RMS) to about 220 V (RMS) for a period of between about 0.5 seconds and about 5 seconds.
Without being limited to a particular theory of operation, it is believed that under particular circumstances, as mentioned herein above, dielectric breakdown and arcing occur upon the delivery of radiofrequency energy, whereby polar molecules are pulled apart. The combination of these factors may result in the creation of an insulative vapor layer around the electrode, therein resulting in an increase in impedance, for example, the impedance may increase to greater than 4000Ω. In some embodiments, despite this high impedance, the voltage continues to increase. Further increasing the voltage increases the intensity of fulguration, which may be desirable as it allows for an increased perforation rate. An example of an appropriate generator for this application is the BMC RF Perforation Generator (model number RFP-100, Baylis Medical Company, Montreal, Canada). This generator delivers continuous RF energy at about 460 kHz.
In some embodiments, a dispersive electrode or grounding pad 702 is electrically coupled to the generator 700 for contacting or attaching to a patient's body to provide a return path for the RF energy when the generator 700 is operated in a monopolar mode. Alternatively, in embodiments utilizing a bipolar device, as described hereinabove, a grounding pad is not necessary as a return path for the RF energy is provided by the further conductive component.
In the embodiment illustrated in
In one broad aspect, the electrosurgical medical device 100 is usable to deliver energy to a target site within a patient's body to perforate or create a void or channel in a material at the target site. Further details regarding delivery of energy to a target site within the body may be found in U.S. patent application Ser. No. 13/113,326 (filed on May 23, 2011), Ser. No. 10/347,366 (filed on Jan. 21, 2003, now U.S. Pat. No. 7,112,197), Ser. No. 10/760,749 (filed on Jan. 21, 2004), Ser. No. 10/666,288 (filed on Sep. 19, 2003), and Ser. No. 11/265,304 (filed on Nov. 3, 2005), and U.S. Pat. No. 7,048,733 (application Ser. No. 10/666,301, filed on Sep. 19, 2003) and U.S. Pat. No. 6,565,562 (issued on May 20, 2003), all of which are incorporated herein by reference.
In one specific embodiment, the target site comprises a tissue within the heart of a patient, for example, the atrial septum of the heart. In such an embodiment, the target site may be accessed via the inferior vena cava (IVC), for example, through the femoral vein.
In one such embodiment, an intended user introduces a guidewire into a femoral vein, typically the right femoral vein, and advances it towards the heart. A guiding sheath, for example, a sheath as described in U.S. patent application Ser. No. 10/666,288 (filed on Sep. 19, 2003), previously incorporated herein by reference, is then introduced into the femoral vein over the guidewire, and advanced towards the heart. The distal ends of the guidewire and sheath are then positioned in the superior vena cava. These steps may be performed with the aid of fluoroscopic imaging. When the sheath is in position, a dilator, for example the TorFlex™ Transseptal Dilator of Baylis Medical Company Inc. (Montreal, Canada), or the dilator as described in U.S. patent application Ser. No. 11/727,382 (filed on Mar. 26, 2007), incorporated herein by reference, is introduced into the sheath and over the guidewire, and advanced through the sheath into the superior vena cava. The sheath aids in preventing the dilator from damaging or puncturing vessel walls, for example, in embodiments comprising a substantially stiff dilator. Alternatively, the dilator may be fully inserted into the sheath prior to entering the body, and both may be advanced simultaneously towards the heart. When the guidewire, sheath, and dilator have been positioned in the superior vena cava, the guidewire is removed from the body, and the sheath and dilator are retracted slightly such that they enter the right atrium of the heart. An electrosurgical device, for example medical device 100 described herein above, is then introduced into the lumen of the dilator, and advanced toward the heart.
In this embodiment, after inserting the electrosurgical device into the dilator, the user positions the distal end of the dilator against the atrial septum. The electrosurgical device is then positioned such that electrode 106 is aligned with or protruding slightly from the distal end of the dilator. When the electrosurgical device and the dilator have been properly positioned, for example, against the fossa ovalis of the atrial septum, a variety of additional steps may be performed. These steps may include measuring one or more properties of the target site, for example, an electrogram or ECG (electrocardiogram) tracing and/or a pressure measurement, or delivering material to the target site, for example, delivering a contrast agent through side-port(s) 600 and/or open distal end 206. Such steps may facilitate the localization of the electrode 106 at the desired target site. In addition, as mentioned herein above, the tactile feedback provided by the proposed medical device 100 is usable to facilitate positioning of the electrode 106 at the desired target site.
With the electrosurgical device and the dilator positioned at the target site, energy is delivered from the energy source, through medical device 100, to the target site. For example, energy is delivered through the elongate member 102, to the electrode 106, and into the tissue at the target site. In some embodiments, the energy is delivered at a power of at least about 5 W at a voltage of at least about 75 V (peak-to-peak), and, as described herein above, functions to vaporize cells in the vicinity of the electrode, thereby creating a void or perforation through the tissue at the target site. If the heart was approached via the inferior vena cava, as described herein above, the user applies force in the substantially cranial direction to the handle 110 of the electrosurgical device as energy is being delivered. The force is then transmitted from the handle to the distal portion 112 of the medical device 100, such that the distal portion 112 advances at least partially through the perforation. In these embodiments, when the distal portion 112 has passed through the target tissue, that is, when it has reached the left atrium, energy delivery is stopped. In some embodiments, the step of delivering energy occurs over a period of between about 1 s and about 5 s.
At this point in the procedure, the diameter of the perforation is typically substantially similar to the outer diameter of the distal portion 112. In some examples, the user may wish to enlarge the perforation, such that other devices such as ablation catheters or other surgical devices are able to pass through the perforation. Typically, to do this, the user applies force to the proximal region of the dilator, for example, in the cranial direction if the heart was approached via the inferior vena cava. The force typically causes the distal end of the dilator to enter the perforation and pass through the atrial septum. The electrosurgical device is operable to aid in guiding the dilator through the perforation, by acting as a substantially stiff rail for the dilator. In such embodiments, a curve, for example, curved section 300 of the medical device 100, typically assists in anchoring the electrosurgical device in the left atrium. In typical embodiments, as force is applied, portions of the dilator of larger diameter pass through the perforation, thereby dilating, expanding, or enlarging the perforation. In some embodiments, the user also applies torque to aid in maneuvering the dilator. Alternatively, in embodiments wherein the device is tapered, the device may be advanced further into the left atrium, such that larger portions of the device enter and dilate the perforation.
In some embodiments, when the perforation has been dilated to a suitable size, the user stops advancing the dilator. A guiding sheath is then advanced over the dilator through the perforation. In alternative embodiments, the sheath is advanced simultaneously with the dilator. At this point in the procedure, the user may retract the dilator and the electrosurgical device proximally through the sheath, leaving only the sheath in place in the heart. The user is then able to perform a surgical procedure on the left side of the heart via the sheath, for example, introducing a surgical device into the femoral vein through the sheath for performing a surgical procedure to treat electrical or morphological abnormalities within the left side of the heart.
If an apparatus of the present invention, as described herein above, is used to carry out a procedure as described herein, then the user is able to maintain the ‘feel’ of a mechanical perforator, for example a Brockenbrough™ needle, without requiring a sharp tip and large amounts of mechanical force to perforate the atrial septum. Rather, a radiofrequency perforator, for example, the electrode 106, is used to create a void or channel through the atrial septum, as described herein above, while reducing the risk of accidental puncture of non-target tissues.
In other embodiments, methods of the present invention may be used for treatment procedures involving other regions within the body, and the invention is not limited in this regard. For example, rather than the atrial septum, embodiments of devices, systems, and methods of the present invention can be used to treat pulmonary atresia. In some such embodiments, a sheath is introduced into the vascular system of a patient and guided to the heart, as described herein above. A dilator is then introduced into the sheath, and advanced towards the heart, where it is positioned against the pulmonary valve. An electro surgical device comprising an electrode is then introduced into the proximal region of the dilator, and advanced such that it is also positioned against the pulmonary valve. Energy is then delivered from the energy source, through the electrode of the electrosurgical device, to the pulmonary valve, such that a puncture or void is created as described herein above. When the electrosurgical device has passed through the valve, the user is able to apply a force to the proximal region of the dilator, for example, in a substantially cranial direction. The force can be transmitted to the distal region of the dilator such that the distal region of the dilator enters the puncture and advances through the pulmonary valve. As regions of the dilator of larger diameter pass through the puncture, the puncture or channel becomes dilated.
In other applications, embodiments of a device of the present invention can be used to create voids or channels within or through other tissues of the body, for example within or through the myocardium of the heart. In other embodiments, the device is used to create a channel through a fully or partially occluded lumen within the body. Examples of such lumens include, but are not limited to, blood vessels, the bile duct, airways of the respiratory tract, and vessels and/or tubes of the digestive system, the urinary tract and/or the reproductive system. In such embodiments, the device is typically positioned such that an electrode of the device is substantially adjacent the material to be perforated. Energy is then delivered from an energy source, through the electrode 106, to the target site such that a void, puncture, or channel is created in or through the tissue.
This disclosure describes embodiments of a kit and its constituent components which together form an apparatus in which fluid communication between a medical device's lumen and the surrounding environment is provided by a conduit cooperatively defined by the medical device and a tubular member into which the device is inserted. The medical device and tubular member are configured to fit together such that an outer surface of the distal region of the medical device cooperates with an inner surface of the tubular member to define the conduit between the side-port of the medical device and a distal end of the tubular member. The conduit is operable for a variety of applications including injecting fluid, withdrawing fluid, and measuring pressure. Methods of assembling and using the apparatus are described as well.
This disclosure further describes an electrosurgical device configured for force transmission from a distal portion of the electrosurgical device to a proximal portion of the electrosurgical device to thereby provide tactile feedback to a user. The proximal portion of the device comprises a handle and/or a hub, with the handle (or hub) including an electrical connector (i.e. a connector means) which is configured to receive, in a releasable manner, an electrically conductive component which is operable to be in electrical communication with an energy source to allow the user to puncture a tissue layer. In some cases, a radiofrequency (RF) energy source is used to selectively apply RF energy to the tissue. Typical embodiments of the device include insulation to protect the user and the patient.
Another aspect of the present invention comprises a puncturing device and method to access the left atrium of a heart (or the pericardial cavity), the method comprising delivering energy to the atrial septum (or the parietal pericardium) in a manner which creates a channel substantially through the atrial septum (or the parietal pericardium) and does not result in inadvertent damage to surrounding tissues due to an automatic shut off of energy after the channel has been created. While the disclosed device is suitable for accessing both the left atrium and the pericardial cavity, for the sake of brevity, the description below will focus on gaining access the left atrium of a heart by the delivery energy to the atrial septum. The concepts disclosed below related to an automatic shut off of energy after a channel has been created are applicable to both epicardial and transseptal procedures.
The disclosed device, system, and methods could be used in other procedures. For example, the disclosed system and method could be used for TIPS procedures wherein the tissue being punctured is liver tissue between the inflow portal vein and the outflow hepatic vein of the liver, the anatomical space the device enters into after puncturing is the inflow portal vein, and the material (fluid or tissue) the device enters into after puncturing is blood. The current is sent through the blood for purposes of determining impedance or dielectricity to control the stopping of energy delivery.
Other examples wherein the disclosed device and system may be used include the following wherein the delivery of radiofrequency energy is deactivated automatically after the puncture device has completed the perforation of the target tissue and entered the desired anatomical space. The automatic stopping of energy delivery is controlled by the sensor determining the value of a parameter for the current flowing through the material in the destination anatomical space, which in the examples of this paragraph, is blood. In a Potts Shunt procedure, the tissue being punctured is tissue between the left pulmonary artery and the descending aorta, the anatomical space the device enters into after puncturing is descending aorta, and the material (fluid or tissue) the device enters into after puncturing is blood. For a procedure which includes accessing a blood vessel, the tissue being punctured is a blood vessel wall, the anatomical space the device enters into after puncturing is the blood vessel (or the target vessel), and the material (fluid or tissue) the device enters into after puncturing is blood. In a general procedure for creating a shunt, the tissue being punctured is material between two parts (or anatomical structures) of a body, the anatomical space the device enters into after puncturing is a destination anatomical structure, and the material (fluid or tissue) the device enters into after puncturing is material contained inside of the destination anatomical structure. For a procedure for Transcaval access in TAVR, the tissue being punctured is the tissue between the abdominal aorta and the adjacent inferior vena cava (IVC), the anatomical space the device enters into after puncturing is the abdominal aorta, and the material (fluid or tissue) the device enters into after puncturing is blood. In the above procedures, the current is sent through the material (fluid or tissue) the device enters into after puncturing for purposes of determining impedance or dielectricity to thereby stop the delivery of energy for puncturing.
An example of a device suitable for use with embodiments of a method to puncture the atrial septum of a patient can be seen in
With reference now to
In an alternative embodiment of the invention, the puncturing device 900 is comprised of a wire configured to deliver energy into a tissue (
In typical embodiments, the placement of the electrodes 916 is on the face of the distal tip 912. Some examples of electrode 916 placement are seen in
An alternative embodiment of the device is illustrated in
With reference now to
In one embodiment, the generator has a hardware switch that will respond to a change in impedance to stop the delivery of energy to the energy delivery device 914. An example of such a switch is a comparator that is connected to a gated switch such as a, MOSFET.
In another embodiment, a software algorithm for shutting off energy delivery for puncturing is implemented within the generator, illustrated in the examples of
The above description of the algorithms of
In some embodiments which use dielectric properties, a hardware arrangement to control energy delivery may be employed. In some such examples, the generator has a hardware switch which is responsive to a change in dielectricity at the distal tip. In some examples, a comparator is connected to a gated switch that can be opened if the dielectricity of blood or pericardial fluid (i.e., not the tissue being punctured) is detected, to thereby stop the delivery of energy to the energy delivery device 914.
Alternative embodiments which uses dielectric properties to control the delivery of energy through the energy delivery device 914 are implemented in software algorithms, examples being illustrated in
In the embodiments shown in
A method using the puncturing device previously described comprises the steps of: delivery energy through an energy delivery device to an atrial septum of a patient's heart, advancing the energy delivery device through the atrial septum; and the delivery of energy automatically stopping upon completion of the puncture.
Prior to delivering energy to the septum, a number of steps may be performed. For example, various treatment compositions or medicaments, such as antibiotics or anesthetics, may be administered to the patient, and various diagnostic tests, including imaging, may be performed.
Various approaches to insertion of an electrosurgical device may be used, depending on the accessibility of vasculature. For example, one application of a method of the present invention, uses the embodiment of an electrosurgical device outlined in
A similar procedure may be used with the embodiment described in
Steps (v) to (x) are the same as for the above method.
In an alternative method, access to the right atrium is achieved through the superior vena cava using with the embodiment of the puncturing device described in
(iii) Advancing the puncturing device through the superior vena cava to the right atrium.
Another alternative method is to use the puncturing device 900 to gain access to a pericardial cavity of a heart by puncturing a parietal pericardium. As used herein, the parietal pericardium refers to the two outer layers of the pericardium, including both the fibrous pericardium as well as the parietal layer. Such an embodiment of the method includes the steps of:
In the above embodiment of method of gaining access to a pericardial cavity, the electrical property which changes upon completing the puncture is impedance or dielectricity.
The embodiments of the invention described above are intended to be exemplary only. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims.
It is appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention, which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination.
Although the invention has been described in conjunction with specific embodiments thereof, it is evident that many alternatives, modifications and variations are apparent to those skilled in the art. Accordingly, it is intended to embrace all such alternatives, modifications, and variations that fall within the scope of the appended claims. All publications, patents and patent applications mentioned in this specification are herein incorporated in their entirety by reference into the specification, to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated herein by reference. In addition, citation or identification of any reference in this application shall not be construed as an admission that such reference is available as prior art to the present invention.
This application is a continuation of and claims the benefit of International Application Number PCT/IB2021/059823, entitled “ELECTROSURGICAL DEVICE WITH SENSING,” and filed Oct. 25, 2021, which claims the benefit of U.S. Provisional Application No. 63/105,975, entitled “ELECTROSURGICAL DEVICE WITH SENSING,” and filed Oct. 27, 2020, which are hereby incorporated by reference in their entireties. The following patents and patent applications are herein incorporated by reference, in their entirety, into the specification: U.S. application Ser. No. 14/222,909, filed on Mar. 24, 2014, U.S. application Ser. No. 13/468,939, filed on May 10, 2012, now U.S. Pat. No. 8,679,107, U.S. application Ser. No. 11/905,447, filed on Oct. 1, 2007, now U.S. Pat. No. 8,192,425, U.S. provisional application No. 60/827,452, filed on Sep. 29, 2006, and U.S. provisional application No. 60/884,285, filed on Jan. 10, 2007. Furthermore, the following patents and patent applications are herein incorporated by reference into the specification in their entirety: U.S. application Ser. No. 12/005,316, filed Dec. 27, 2007, U.S. provisional patent application 60/883,074, filed on Jan. 2, 2007. This application also incorporates by reference International application No. PCT/IB2019/053751 filed 7 May 2019, U.S. application Ser. No. 13/656,193 filed Oct. 19, 2012 and U.S. application Ser. No. 14/257,053 filed Apr. 21, 2014, in their entirety.
Number | Date | Country | |
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63105975 | Oct 2020 | US |
Number | Date | Country | |
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Parent | PCT/IB2021/059823 | Oct 2021 | US |
Child | 18308415 | US |