Pressure Relief Function of Infusion-Type RF Balloon Catheter

Abstract

To provide a catheter system and a method.SOLUTION: An apparatus includes a catheter shaft assembly, and an end effector positioned at a distal end of the catheter shaft assembly. The end effector includes a balloon, one or more electrodes on the balloon, and a tip assembly at a distal end of the balloon. The balloon defines an interior configured to receive fluid to inflate the balloon. The balloon is sized and configured to fit into a cardiovascular anatomical structure. The tip assembly includes a pressure relief valve that is configured to transition between a sealing state and a pressure-relieving state. In the sealing state, the pressure relief valve is configured to prevent the fluid from leaking from the interior of the balloon via the pressure relief valve. In the pressure-relieving state, the pressure relief valve is configured to provide a path for the fluid leaking from the interior of the balloon via the pressure relief valve.SELECTED DRAWING: Figure 1

Description

Background Art

[0001] Cardiac arrhythmias such as atrial fibrillation occur when regions of cardiac tissue transmit electrical signals abnormally. Treatments for arrhythmias include surgically disrupting such signal transmission pathways. By selectively ablating cardiac tissue by applying energy (e.g., radiofrequency (RF) energy), it may be possible to stop or modify the propagation of unwanted electrical signals from one part of the heart to another. The ablation process can provide a barrier to unwanted electrical pathways by forming a denatured or scar tissue with electrical insulation, effectively blocking the transmission of abnormal electrical signals attempting to pass through the tissue.

[0002] In some procedures, a catheter with one or more RF electrodes can be used to provide ablation within the cardiovascular system. The catheter can be inserted into a major vein or artery (e.g., the femoral artery) and then advanced to position the electrodes within the heart or within a cardiovascular structure adjacent to the heart (e.g., the pulmonary vein). One or more electrodes can be placed in contact with cardiac tissue or other vascular tissue and then ablated by activating with RF energy. In some cases, the electrodes may be bipolar. In some other cases, monopolar electrodes may be used in combination with a ground pad or other reference electrode in contact with the patient. By using irrigation, heat can be drawn away from the ablation component of the ablation catheter, preventing the formation of blood clots near the ablation site.

[0003] Examples of ablation catheters are described in U.S. Patent Application Publication No. 2013 / 0030426, published January 31, 2013, titled "Integrated Ablation System using Catheter with Multiple Irrigation Lumens" (the disclosure of which is incorporated herein by reference in its entirety), U.S. Patent Application Publication No. 2017 / 0312022, published November 2, 2017, titled "Irrigated Balloon Catheter with Flexible Circuit Electrode Assembly" (the disclosure of which is incorporated herein by reference in its entirety), and U.S. Patent No. 10,130,422, issued November 20, 2018, titled "Catheter with Soft Distal Tip for Mapping and Ablating Tubular Region" (the disclosure of which is incorporated herein by reference in its entirety).

[0004] Some catheter ablation procedures can be performed after using electrophysiology (EP) mapping to identify the tissue region to be ablated. Such EP mapping may include the use of sensing electrodes on a catheter (e.g., the same catheter used to perform ablation or a dedicated mapping catheter). Such sensing electrodes can monitor electrical signals emitted from conductive endocardial tissue to accurately indicate the location of abnormal conductive tissue sites involved in arrhythmias. Examples of EP mapping systems and catheters are described in various references cited herein.

[0005] In addition to using force sensing or EP mapping, some catheter ablation procedures may be performed using an image guided surgery (IGS) system. The IGS system may enable a physician to visually track the position of a catheter within a patient in real time in relation to an image of anatomical structures within the patient. Some systems can provide a combination of an EP mapping function and an IGS function (for example, the CARTO 3® system by Biosense Webster, Inc. (Irvine, California)). Examples of catheters configured to be used with an IGS system are disclosed in various references cited herein.

[0006] Although several catheter systems and methods have been made and utilized, prior to the inventors, there are believed to be none that have made or utilized the invention as described in the appended claims.

Brief Description of the Drawings

[0007] The following drawings and detailed description are merely illustrative and are not intended to limit the scope of the invention contemplated by the inventors.

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Figure 10B

Mode for Carrying Out the Invention

[0008] The following description of specific embodiments of the present invention should not be used for the purpose of limiting the scope of the present invention. The drawings are not necessarily to scale and show selected embodiments and are not intended to limit the scope of the present invention. The detailed description is not intended to limit the principles of the present invention but is illustrative by way of example. Other embodiments, features, aspects, embodiments, and advantages of the present invention will become apparent to those skilled in the art from the following description which shows one of the best modes contemplated for carrying out the present invention as an example. As will be understood, the present invention is capable of other different modes or equivalent modes without departing from the present invention. Therefore, the drawings and the description should be regarded as being of an illustrative nature rather than a limiting nature.

[0009] Any one or more of the teachings, expressions, variations, examples, etc. described in this specification can be combined with any one or more of the other teachings, expressions, variations, examples, etc. described in this specification. Therefore, the teachings, expressions, variations, examples, etc. described below should not be considered independently of each other. In light of the teachings of this specification, various suitable ways of combining the teachings of this specification will be readily apparent to those skilled in the art. Such modifications and variations are intended to be included within the scope of the "claims".

[0010] As used herein, the terms "about", "substantially", "approximately", or "nearly" with respect to any numerical value or range of numerical values indicate a preferred dimensional tolerance range that allows a part of a component or a set of components to function in accordance with the intended purpose described herein. More specifically, "about" or "approximately" can refer to a range of values within ±20% of the recited value. For example, "about 90%" can refer to a range of values from 71% to 99%. Further, as used herein, the terms "patient", "host", "user", and "subject" refer to any human or animal subject and are not intended to limit the use of the above-described system or method to use in humans, although the use of the present invention in human patients represents a preferred embodiment.

[0011] I. Overview of an Exemplary Catheter System FIG. 1 shows an exemplary medical procedure and related components of a cardiac mapping or ablation system. Specifically, FIG. 1 shows a physician (PH) gripping the handle (110) of a catheter assembly (100), with the end effector (200) of the flexible catheter (120) of the catheter assembly (100) (shown in FIGS. 2A-7B but not in FIG. 1) disposed within a patient (PA) to map or ablate tissue within or near the patient's heart (H). As shown in FIGS. 2A-2C, the catheter (120) includes an outer shaft (122) and an outer sheath (140), and the outer sheath (140) is operable to selectively cover and uncover the end effector (200) disposed at the distal end (124) of the outer shaft (122). In some variations, the handle (110) includes an actuator (not shown) operable to translate the sheath (140) relative to the end effector (200) and the outer shaft (122). In some other variations, the handle (110) includes an actuator (not shown) operable to translate the end effector (200) and the outer shaft (122) relative to the sheath (140). The catheter (120) of the present example further includes an inner shaft (150) (shown in phantom lines in FIGS. 7A and 7B) extending through the end effector (200). The inner shaft (150) defines a lumen (152) configured to slidably receive another instrument such as a guide wire or another catheter.

[0012] In some alternative variations, rather than the sheath (140) being an integral part of the catheter (120), instead the sheath (140) may be part of a separate guiding sheath instrument, and the catheter (120) and the end effector (200) may be inserted through the guiding sheath instrument such that the end effector (200) can be positioned at an appropriate location within the patient (PA).

[0013] The catheter assembly (100) is coupled to the induction drive system (10) via a cable (30). In this example, a plug (not shown) of the cable (30) is configured to be inserted into a socket (130) of the handle assembly (110) shown in FIGS. 2A and 2B. The induction drive system (10) of this example includes a console (12) and a display (18). The console (12) includes a first driver module (14) and a second driver module (16). The first driver module (14) is coupled to the catheter assembly (100) via the cable (30). In some variations, the first driver module (14) is operable to receive an EP mapping signal obtained via an electrode pair (not shown) of the end effector (200), as described in more detail below. The console (12) includes a processor (not shown) that processes such an EP mapping signal, thereby performing EP mapping known in the art. Additionally or alternatively, the first driver module (14) may be operable to supply RF power to the ablation electrode (214) of the end effector (200), thereby ablating tissue, as described in more detail below. In some variations, the first driver module (14) is also operable to receive a position indication signal from one or more position sensors (206) within the end effector (200), as described in more detail below. In such variations, the processor of the console (12) is also operable to process the position indication signal from the position sensors (206), thereby determining the position of the end effector (200) within the patient (PA).

[0014] A set of magnetic field generators (20) is positioned under the patient (PA) and connected to the induction drive system (10) via a cable (22). Specifically, a second driver module (16) is connected to the magnetic field generator (20) via the cable (22). The second driver module (16) is operable to activate the magnetic field generator (20) to generate an alternating magnetic field around the patient's (PA) heart (H). For example, the magnetic field generator (20) may include a coil that generates an alternating magnetic field within a predetermined working volume that includes the heart (H).

[0015] The display (18) is connected to the processor of the console (12) and is operable to render an image of the patient's anatomical structure. Such an image may be based on a set of pre-operative or intra-operative acquired images (e.g., CT or MRI scans, 3D maps, etc.). The diagram of the patient's anatomical structure provided through the display (18) may also change dynamically based on signals from the position sensor (206) of the end effector (200). For example, as the end effector (200) moves within the patient (PA), the corresponding position data from the position sensor (206) causes the processor of the console (12) to update the diagram of the patient's anatomical structure within the display (18) in real time, depicting the area of the patient's anatomical structure around the end effector (200) as the end effector (200) moves within the patient (PA). Further, the processor of the console (12) may drive the display (18) to indicate the location of abnormal conductive tissue sites as detected by EP mapping by the end effector (200). By way of example only, the processor of the console (12) may drive the display (18) to overlay the location of abnormal conductive tissue sites on the image of the patient's anatomical structure, for example, by overlaying dots, crosshairs, or some other form of visual indication of the abnormal conductive tissue site.

[0016] The processor of the console (12) may also drive the display (18) to overlay the current position of the end effector (200) on an image of the patient's anatomical structure, such as by overlaying illuminated dots, crosshairs, a graphic representation of the end effector (200), or some other form of visual display. Such an overlaid visual display can also move in real time within the image of the patient's anatomical structure on the display (18) as the physician moves the end effector (200) within the patient (PA). Thereby, when the end effector (200) moves within the patient (PA), real-time visual feedback regarding the position of the end effector (200) within the patient (PA) can be provided to the operator. Thus, the image provided through the display (18) can effectively provide a video tracking the position of the end effector (200) within the patient (PA) without necessarily using any optical device (i.e., camera) for viewing the end effector (200). In the same figure, the display (18) can simultaneously visually indicate the position of the abnormal conductive tissue site detected by the EP mapping described herein. Thus, the physician (PH) can observe in real time, by looking at the display (18), the positioning of the end effector (200) relative to the mapped abnormal conductive tissue site and also relative to the image of the adjacent anatomical structures within the patient (PA).

[0017] The catheter assembly (100) is connected to a fluid source (42) via a fluid conduit (40). The fluid conduit (40) is configured to be connected to a fluid input portion (130) of the handle assembly (110) shown in FIGS. 2A-2C. Such connection can be achieved using a conventional luer fitting or any other suitable type of connector. The fluid source (42) in this example includes a bag containing saline or some other suitable perfusion fluid. The conduit (40) includes a flexible tube further connected to a pump (44) operable to selectively carry fluid from the fluid source (42) to the catheter assembly (100). In some variations, the conduit (40), the fluid source (42), and the pump (44) are completely omitted. In variations that include these components, the end effector (200) may be configured to communicate perfusion fluid from the fluid source (42) to a target site within the patient. Such perfusion can be performed according to the teachings of any of the various patent references cited herein or in any other suitable manner as would be apparent to one of ordinary skill in the art in view of the teachings herein.

[0018] II. Exemplary End Effector FIG. 3 shows the end effector (200) of this example in more detail. As shown, the end effector (200) includes an expandable balloon (202) and a set of electrode assemblies (210) angularly spaced from each other around the balloon (202). The balloon (202) is operable to transition between a non-expanded state (FIGS. 2A and 2B) and an expanded state (FIGS. 2C and 3 and FIGS. 7A and 7B). The balloon (202) can be inflated with perfusion fluid (e.g., saline) from the fluid source (42) pressurized by the pump (44) to transition from the non-expanded state to the expanded state. In the non-expanded state, the balloon (202) can fit within the sheath (140). In the expanded state, the balloon (202) can be sized and configured to bias the electrodes (214) of the electrode assemblies (210) into contact with tissue (e.g., the inner wall of a pulmonary vein or a cardiac chamber of the heart (H)). In this example, the balloon (202) is formed from a flexible but non-extensible material.

[0019] The balloon (202) of this example includes a plurality of openings (204). Although only a few openings (204) are shown in FIG. 3, the balloon (202) may actually have a significant number of openings. The openings (204) may be large enough for fluid to leak through the balloon (202) to the site where the electrode assembly (210) ablates tissue, but at the same time small enough to allow the balloon (202) to expand in response to the pressurized fluid transmitted into the interior of the balloon (202). By way of example only, the openings (204) may be about 0.0035 inches in diameter. Alternatively, the openings (204) may be any other suitable size, examples of which include, but are not limited to, diameters in the range of about 0.0100 inches to about 0.0010 inches.

[0020] Each electrode assembly (210) of this example includes a flexible substrate (212) and an electrode (214). The substrate (212) and the electrode (214) may be formed as a flex circuit. The sides of each substrate (212) are defined by longitudinally extending beams (224). Each longitudinally extending beam (224) is further coupled to a central transverse beam (220) and a distal transverse beam (222). In some variations, the beams (220, 222, 224) assist in fixing the electrode assembly (210) to the balloon (202). Alternatively, the beams (220, 222, 224) may join other components of the end effector (200) together. In some variations, the beams (220, 222, 224) are defined by elongated edges of an adhesive. The electrode assembly (210) is shown as being positioned only on the distal side of the central transverse beam (220), but some variations of the end effector (200) may include the electrode assembly (210) on the proximal side of the central transverse beam (220). Further, the illustrated configuration and arrangement of the beams (220, 222, 224) are merely exemplary embodiments. The beams (220, 222, 224) may be reconfigured, rearranged, supplemented, replaced, or omitted as desired.

[0021] The electrode (214) of this example is operable to ablate tissue in contact with the electrode (214). Each electrode (214) of this example includes a central elongated portion or spine, and a plurality of finger portions extend transversely from the central spine. Thus, each electrode (214) has a fishbone configuration. Such a fishbone configuration can advantageously increase the circumferential or equatorial contact surface of each electrode (214) with the target tissue, while the gap between adjacent finger portions of the electrode (214) can advantageously allow the balloon (202) to be folded inwardly and / or expanded radially at positions along its equator as needed. In some variations, the finger portions of each electrode (214) have different lengths from each other, some being longer and others shorter. For example, the finger portions of each electrode (214) may have lengths that gradually decrease along the length of the central spine of the electrode (214), providing a generally tapered configuration to each electrode (214). The electrode (214) may be further configured and operable at least in part according to the teachings of U.S. Patent Application Publication No. 2017 / 0312022, entitled "Irrigated Balloon Catheter with Flexible Circuit Electrode Assembly", published on November 2, 2017, the disclosure of which is hereby incorporated by reference in its entirety.

[0022] In some variations, the electrode (214) is configured to provide both an RF ablation function and an EP mapping function. In some other variations, the electrode (214) is configured to provide only the RF ablation function without providing the EP mapping function. In still other variations, the electrode (214) is configured to provide only the EP mapping function without providing the RF ablation function. As yet another merely illustrative example, the end effector (200) can include some electrodes (214) that are dedicated to providing only the RF ablation function and other electrodes that are dedicated to providing only the EP mapping function. Other suitable configurations and functions that can be associated with the electrode (214) will be apparent to those skilled in the art in view of the teachings herein.

[0023] In some variations of the ablation catheter (120) that includes some electrodes (214) dedicated to providing only the RF ablation function and other electrodes dedicated to providing only the EP mapping function, the distal region of the end effector (200) may include electrodes dedicated to EP mapping. Such EP mapping electrodes can be positioned distally of the electrode (214). Such EP mapping electrodes may be separated from the electrode (214). Such EP mapping electrodes may be used to assist in identifying the target region for RF ablation before the RF ablation is applied. Such EP mapping electrodes may also be used to verify whether the RF ablation was sufficient after the RF ablation was applied. Further, such EP mapping electrodes can monitor the electrocardiogram signal in real time during RF ablation to provide real-time feedback regarding the effectiveness of the RF ablation.

[0024] The end effector (200) of this example further includes a distal hub (230) having an integral, distally extending cylindrical member (232). The distal hub (230) can be attached to the balloon (202) in any suitable manner that would be apparent to one of ordinary skill in the art in view of the teachings herein. As described above, the end effector (200) also includes a position sensor (206). FIGS. 3 and 4 schematically show the position sensor (206) integrated into the cylindrical member (232) of the distal hub (230). Alternatively, the end effector (200) may include one or more position sensors (206) at any other suitable location in addition to, or instead of, the position sensor (206) within the cylindrical member (232).

[0025] The position sensor (206) is operable to generate a signal indicative of the position and orientation of the end effector (200) within the patient (PA). By way of example only, the position sensor (206) can be in the form of one wire coil or multiple wire coils (e.g., three orthogonal coils) configured to generate an electrical signal in response to the presence of an alternating electromagnetic field generated by a magnetic field generator (20). The position sensor (206) may be coupled to a wire, trace, or any other suitable electrical conduit along or through the catheter (120) in such a way that the signal generated by the position sensor (206) can be transmitted to the console (12) through an electrical conduit (not shown) within the catheter (120). The console (12) can process the signal from the position sensor (206) to identify the position of the end effector (200) within the patient (PA). Other components and techniques that can be used to generate real-time position data associated with the end effector (200) can include wireless triangulation, acoustic tracking, optical tracking, inertial tracking, and the like. In some variations, the position sensor (206) may be omitted. As another merely exemplary embodiment, the position sensor (206) may be integrated into another instrument (e.g., a guide wire or catheter) slidably disposed within the lumen (152) of the inner shaft (150).

[0026] During use of the catheter assembly (100), when the catheter (120) is introduced into the patient's body (PA) and during its transition from the insertion site to the target cardiovascular region within the patient (PA), the catheter (120), the sheath (140), and the end effector (200) can be in the state shown in FIG. 2A. Once the catheter (120), the sheath (140), and the end effector (200) are suitably positioned near the target cardiovascular structure, the sheath (140) can be retracted relative to the end effector (200) (or the end effector (200) can be advanced relative to the sheath (140)) to reach the state shown in FIG. 2B. Next, the end effector (200) can be expanded by inflating the balloon (202) to bring the electrodes (214) into contact with the tissue of the target cardiovascular structure. After the electrodes (214) contact the target tissue, the electrodes (214) can be activated to apply RF energy to the tissue to ablate the tissue. The RF energy can be supplied from the console (12) through various components that electrically couple the electrodes (214) to the console (12) as described above. Next, the balloon (202) can be deflated to fold the end effector (200) into a non-expanded configuration. Then, the catheter (120), the sheath (140), and the end effector (200) can be removed from the patient (PA). During at least some of the steps described above, the physician (PA) can observe the display (18) to confirm the real-time position of the end effector (200) and / or other components of the catheter assembly (100) based on the position data from the position sensor (206).

[0027] In addition to the above, other aspects of the end effector (200) and the catheter assembly (100) can be configured and operable according to at least a portion of the teachings of U.S. Patent Application Publication No. 2017 / 0312022, published on November 2, 2017, with the title "Irrigated Balloon Catheter with Flexible Circuit Electrode Assembly" (the disclosure of which is hereby incorporated by reference in its entirety).

[0028] A. Example of an elastic O-ring functioning as a relief valve As described above, the balloon (202) can be inflated with inflation fluid leaking from the balloon (202) through the opening (204). If the ablation or mapping procedure is complete and the physician (PH) desires to return the balloon (202) to its deflated state and remove the end effector (200) from the patient (PA), the physician can stop the fluid communication to the balloon (202). As the fluid leaks through the opening (204), the balloon (202) will eventually contract to the deflated state shown in Figure 2B, enabling the physician (PH) to place the end effector (200) back into the sheath (140) and withdraw the catheter (120) and the end effector (200) from the patient (PA). If the physician (PA) does not provide sufficient time for the fluid to leak through the opening (204) in a manner sufficient to achieve complete contraction of the balloon (202), the physician (PA) may encounter troublesome problems if attempting to place the end effector (200) into the sheath (140) or attempting to remove the end effector (200) from the patient (PA). Thus, it may be desirable to provide a functional component that provides an additional means for relieving pressure from the balloon (202) during the contraction phase. For that purpose, the end effector (200) of this example includes a tip assembly (250) configured to provide an additional pressure relief function for the balloon (202) during the contraction phase.

[0029] As shown in FIGS. 4-7B, the tip assembly (250) of this example includes a body (252) having a distal annular flange portion (254) and a proximal cylindrical portion (256). The cylindrical portion (256) has an outer diameter sized such that, as shown in FIG. 3, the cylindrical portion (256) can fit within the cylindrical member (232) of the distal hub (230). With the cylindrical portion (256) of the body (252) fully inserted within the cylindrical member (232) of the distal hub (230), the body (252) may be coupled to the cylindrical member (232) of the distal hub (230) by interference fit, using an adhesive or epoxy, using welding, or using any other suitable technique that would be apparent to one of ordinary skill in the art in view of the teachings herein. The flange portion (254) is sized larger than the cylindrical member (232) of the distal hub (230), such that, again as shown in FIG. 3, the flange portion (254) is positioned distally of the cylindrical member (232) of the distal hub (230), while the cylindrical portion (256) of the body (252) is seated within the cylindrical member (232) of the distal hub (230).

[0030] The hole (270) extends along the entire length of the body (252) through the flange portion (254) and the cylindrical portion (256), and the body (252) is hollow. The diameter of the hole (270) passing through the cylindrical portion (256) is larger than the diameter of the hole (270) passing through the flange portion (254). As shown in FIGS. 7A and 7B, the inner annular shoulder (280) provides a stepped transition from the region of the hole (270) within the cylindrical portion (256) to the region of the hole (270) within the flange portion (254). The region of the hole (270) within the cylindrical portion (256) is sized to receive the inner shaft (150) of the catheter (120) as shown in FIGS. 6 - 7B. The diameter of the hole (270) passing through the flange portion (254) is smaller than the outer diameter of the inner shaft (150) such that the inner shaft (150) does not fit within the region of the hole (270) within the flange portion (254). Thus, when the inner shaft (150) is fully inserted into the hole (270), the distal end of the inner shaft (150) abuts against the shoulder (280). With the inner shaft (150) fully inserted into the hole (270), the inner shaft (150) may be coupled to the body (252) by interference fit, using an adhesive or epoxy, using welding, or using any other suitable technique that would be apparent to one of ordinary skill in the art in view of the teachings herein. As shown in FIGS. 7A and 7B, the region of the hole (270) within the flange portion (254) is aligned with the lumen (152) of the inner shaft (150), and an instrument (e.g., a guidewire, an EP mapping catheter, etc.) may pass through the lumen (152) and further through the region of the hole (270) within the flange portion (254) and be positioned distally with respect to the tip assembly (250) as desired. This is not necessarily required in all variations.

[0031] The cylindrical portion (254) defines a plurality of lateral openings (257) that communicate with the hole (270). In this example, the openings (257) are arranged alternately in the longitudinal and diagonal directions relative to each other along the cylindrical portion (254), but the openings (257) may be arranged in any other suitable manner along the cylindrical portion (254). In some variations, the openings (257) are used to hold an adhesive, epoxy, or some other substance used to couple the inner shaft (150) to the body (252). In other words, the openings (257) can function as weep holes for adhesion. In some other variations, the openings (257) are omitted.

[0032] The body (252) also defines two longitudinally extending recesses (258) that extend along the hole (270) within the cylindrical portion (254). The recesses (258) are angularly offset from each other by 180 degrees in this example. In another variation, only a single recess (258) may be used, or three or more recesses (258) may be used. The recesses (258) may also be arranged along the hole (270) in any other suitable pattern. In this example, the recesses (258) and the openings (257) are angularly offset from each other so that the openings (257) do not penetrate the recesses (258). As best seen in FIGS. 6 - 7B, when the inner shaft (150) seats within the region of the hole (270) within the cylindrical portion (256), a passageway (290) is defined between the recess (258) and the outer diameter of the inner shaft (150). As also shown in FIGS. 7A and 7B, these passageways (290) are in fluid communication with the interior of the balloon (202), and as described in more detail below, the passageways (290) can provide a path for discharging fluid from the balloon (202).

[0033] The body (252) also includes an annular recess (262) positioned between the annular flange portion (252) and the cylindrical portion (254). The recess (262) includes a pair of lateral openings (264). Each opening (264) is at the distal end of a corresponding recess (258), and each recess (258) is in fluid communication with a corresponding opening (258). Each opening (264) is also sized and positioned to be in fluid communication with a corresponding passageway (290) with the inner shaft (150) seated within the region of the hole (270) in the cylindrical portion (256). The recess (262) is sized to receive an O-ring (260). The O-ring (260) is sized and configured such that, as shown in FIGS. 3 and 7A, the O-ring (260) is elastically biased to seat snugly within the recess (262). However, the O-ring (260) is also configured to expand radially outward in response to sufficient fluid pressure applied to the O-ring (260), as shown in FIG. 7B and described in more detail below. As shown in FIGS. 3 and 7A and 7B, with the cylindrical portion (256) of the body (252) fully seated within the cylindrical member (232) of the distal hub (230), the O-ring (260) is positioned longitudinally between the flange portion of the body (254) and the distal end of the cylindrical member (232) of the distal hub (230). Although an O-ring (260) is used in this example, any other suitable type of sealing member may be used instead of the O-ring (260), examples of which include, but are not limited to, an annular band or a structure having a flat cross-sectional profile. Other suitable types of sealing members will be apparent to those skilled in the art in view of the teachings herein.

[0034] FIG. 7A shows the tip assembly (250) during normal operation of the end effector (200). As shown, due to the elasticity of the O-ring (260), the O-ring (260) fits snugly into the opening (264) within the recess (262). In this state, the O-ring (260) prevents fluid from flowing out of the interior of the balloon (202) through the passageway (290) and the opening (264). Thus, when the balloon (202) is inflated and pressed against the tissue to bias the electrode (214) against the tissue, the O-ring (290) continues to seal the opening (264), and as a result, fluid can only flow out of the balloon (202) through the opening (204).

[0035] As described above, even when the physician (PH) desires to deflate the balloon (202) by stopping the fluid communication to the balloon (202) at the end of the procedure, the fluid remaining within the balloon (202) may not leak through the opening (204) as rapidly as the physician (PH) expects. Under such a scenario, if the physician (PH) attempts to place the end effector (200) within the sheath (140) or otherwise remove the end effector (200) from the patient (PA) before sufficient fluid has leaked out of the balloon (202), this attempt by the physician (PH) can cause a rapid increase in the pressure of the fluid remaining within the balloon (202). In such a case, the rapid increase in the fluid pressure can drive the O-ring (260) to expand radially outwardly, as shown in FIG. 7B. When the O-ring (260) expands radially outwardly to the state shown in FIG. 7B, the O-ring (260) expands outwardly in a direction away from the central longitudinal axis (LA) shown in FIG. 3 of the catheter (120) and the end effector (200).

[0036] When the O-ring (260) is in the outwardly expanded state shown in FIG. 7B, a gap (292) is defined between the O-ring (260) and the recess (262). These gaps (292) provide a path for fluid to leak from the balloon (202) through the passageway (290), the opening (264), and the gap (292). Thus, the O-ring (260) provides a relief valve to assist in discharging fluid from the balloon (202) when the pressure of the fluid in the balloon (202) rises rapidly. When the fluid pressure is relieved, due to the elasticity of the O-ring (260), the O-ring (260) returns to the state shown in FIG. 7A. In this case, the end effector (200) can be removed from the patient (PA).

[0037] In some variations, the O-ring (260) can be configured to transition from the contracted sealing state of FIG. 7A to the expanded pressure-relieving state of FIG. 7B in response to fluid pressure within the balloon (202) exceeding a pressure threshold in the range of about 1.50 psi to about 8.00 psi. Alternatively, any other suitable pressure threshold may be indicated by the O-ring (260).

[0038] B. Example of an End Effector with a Spring Loaded Relief Valve FIGS. 8-10B show another exemplary end effector (300) that can be incorporated into the catheter assembly (100) instead of the end effector (200). Except as otherwise described below, the end effector (300) of this example is generally the same as the end effector (200). Similar to the end effector (200), the end effector (300) of this example includes a balloon (302) having an opening (304), an electrode assembly (310) having a substrate (312) and electrodes (314), beams (320, 322, 324), and a distal hub (330) having a cylindrical member (332) extending distally and a position sensor (306). These components of the end effector (300) are configured and operable like the similarly named components of the end effector (200), and the details of these components are not repeated here.

[0039] The end effector (300) of the present example also includes a distal tip assembly (350) configured to be different from the tip assembly (250) of the end effector (200), and the tip assembly (350) is operable to provide a pressure relief valve for the balloon (302). As best shown in FIG. 9, the tip assembly (350) of the present example includes a distal annular member (352), an O-ring (360), a first cylindrical body (354), and a second cylindrical body (370). The distal annular member (352) defines a central opening (353). The first cylindrical body (354) defines a grooved hole (356) including a plurality of longitudinally extending recesses angularly spaced from each other. The second cylindrical body (370) also defines a hole (372). An annular flange (382) is fixedly attached (e.g., via an adhesive, welding, etc.) near the proximal end of the second cylindrical body (370). A wave spring (380) is disposed around the outside of the second cylindrical body (370).

[0040] The second cylindrical body (370) is slidably disposed within the grooved hole (356) of the first cylindrical body (354). As shown in FIGS. 10A-10B, since the hole (356) is configured with grooves, a longitudinally extending gap (390) is provided between the outer diameter of the second cylindrical body (370) and each groove recess defined within the hole (356). These longitudinally extending gaps (390) provide a path for discharging fluid from the balloon (302), as described in more detail below.

[0041] As shown in FIGS. 8 and 10A and 10B, the first cylindrical body (354) is configured to fit within the cylindrical member (332) of the distal hub (330). Further, the first cylindrical body (354) is coupled to the cylindrical member (332) of the distal hub (330). This coupling can be achieved by interference fit, using an adhesive or epoxy, using welding, or any other suitable technique that would be apparent to one of ordinary skill in the art in view of the teachings herein. As best seen in FIGS. 10A and 10B, the distal annular member (352) is fixedly attached to the distal end of the second cylindrical body (370). By way of example only, the distal annular member (352) can be attached to the distal end of the second cylindrical body (370) by interference fit, using an adhesive or epoxy, using welding, or any other suitable technique that would be apparent to one of ordinary skill in the art in view of the teachings herein.

[0042] As also shown in FIGS. 10A and 10B, the inner shaft (150) of the catheter (120) (shown in phantom lines in FIGS. 10A and 10B) is disposed within the hole (372) of the second cylindrical body (370). In some variations, the inner shaft (150) is fixedly attached to the second cylindrical body (370) by an interference fit, using an adhesive or epoxy, using welding, or using any other suitable technique that would be apparent to one of ordinary skill in the art in view of the teachings herein. Additionally or alternatively, the distal end of the inner shaft (150) can be fixedly attached to the distal annular member (352) (e.g., using an adhesive or epoxy, using welding, or using any other suitable technique that would be apparent to one of ordinary skill in the art in view of the teachings herein). In some variations, the connection between the inner shaft (150) and the second cylindrical body (370) or the distal annular member (352) allows for at least some longitudinal relative movement between the inner shaft (150) and the combination of the second cylindrical body (370) and the distal annular member (352). In some such variations, such relative longitudinal movement is allowed, but such relative longitudinal movement may be restricted by one or more limiting structures that would be apparent to one of ordinary skill in the art in view of the teachings herein.

[0043] In this example, the lumen (152) of the inner shaft (150) is aligned and in communication with the central opening (353) of the distal annular member (352). Thus, an instrument (e.g., a guidewire, an EP mapping catheter, etc.) can be positioned distally relative to the tip assembly (350) through the lumen (152) and the central opening (353), if desired. This is not necessarily required in all variations.

[0044] As shown in FIGS. 10A and 10B, the longitudinal distance between the annular flange (382) and the distal annular member (352) is longer than the length of the first cylindrical body (354). This relative sizing allows the wave spring (380) to be captured between the annular flange (382) and the proximal end of the first cylindrical body (354). This relative sizing also allows an O-ring (360) to be captured between the distal end of the cylindrical member (332) and the distal annular member (352). Further, this relative sizing allows the first cylindrical body (354) to move longitudinally to some extent relative to the combination of the annular flange (382), the second cylindrical body (370), and the distal annular member (352).

[0045] The wave spring (380) is configured to be compressed distally against the proximal end of the first cylindrical body (354), thereby elastically biasing the distal end of the cylindrical member (332) to engage the O-ring (360). By way of example only, the wave spring (380) may be configured to elastically bias the distal end of the cylindrical member (332) to engage the O-ring (360) with a load in the range of about 0.5 foot-pounds to about 1.5 foot-pounds. When the distal end of the cylindrical member (332) is engaged with the O-ring (360) as shown in FIG. 10A, the distal end of the cylindrical member (332) and the O-ring (360) cooperate to seal the distal end of a longitudinally extending gap (390) defined between the outer diameter of the second cylindrical body (370) and each groove recess defined within the hole (356). Thus, when the tip assembly (350) is in the state shown in FIG. 10A, the distal end of the cylindrical member (332) and the O-ring (360) cooperate to prevent the inflation fluid within the balloon (302) from leaking through the tip assembly (350). The wave spring (380) maintains the tip assembly (350) in the state shown in FIG. 10A during normal operation of the end effector (300). In this state, when the balloon (302) expands and is pressed against the tissue, thereby biasing the electrode (314) against the tissue, the fluid can only flow out of the balloon (302) through the opening (304).

[0046] As described above, even when the physician (PH) desires to deflate the balloon (302) by stopping the flow of fluid to the balloon (302) at the end of the procedure, the fluid remaining within the balloon (302) may not leak through the opening (304) as quickly as the physician (PH) expects. Under such a scenario, before sufficient fluid leaks out of the balloon (302), if the physician (PH) attempts to place the end effector (300) within the sheath (140) or otherwise remove the end effector (300) from the patient (PA), this attempt by the physician (PH) may cause a rapid increase in the pressure of the fluid remaining within the balloon (302). In such a case, the rapid increase in fluid pressure can drive the cylindrical member (332) and the first cylindrical body (354) to translate proximally relative to the inner shaft (150) and also proximally relative to the remainder of the distal assembly (350), as shown in FIG. 10B. In this state, the proximal movement of the cylindrical member (332) and the first cylindrical body (354) relative to the remainder of the distal assembly (350) separates the space between the O-ring (360) and the distal end of the cylindrical member (332), defining a gap (392). In this example, the wave spring (380) deforms to enable the cylindrical member (332) and the first cylindrical body (354) to translate proximally relative to the inner shaft (150) and also relative to the remainder of the distal assembly (350). By way of example only, the wave spring (380) deforms to the state shown in FIG. 10B in response to a load in the range of approximately 2.0 foot-pounds to approximately 5.0 foot-pounds. When the wave spring (380) deforms to the state shown in FIG. 10B, the wave spring (380) is compressed along the central longitudinal axis (LA) of the catheter (120) and the end effector (300) as shown in FIG. 8. The first cylindrical body (354) translates along this central longitudinal axis (LA) relative to the remainder of the distal assembly (350) during the transition between the state shown in FIG. 10A and the state shown in FIG. 10B.

[0047] As shown in FIG. 10B, even when the cylindrical member (332) and the first cylindrical body (354) are in a proximal position relative to the remaining portion of the distal assembly (350), there is still sufficient clearance between the annular flange (382) and the proximal end of the first cylindrical body (354) to allow fluid to flow from inside the balloon (302) into the clearance (390) defined between the outer diameter of the second cylindrical body (370) and each groove recess defined within the hole (356). Thus, the cylindrical member (332) and the distal assembly (350) cooperate to provide a path for fluid to leak from the balloon (302) through the clearances (390, 392). Thus, the distal assembly (350) provides a relief valve to assist in discharging fluid from the balloon (302) when the pressure of the fluid within the balloon (302) rapidly increases.

[0048] Once the fluid pressure is released from the balloon (302), the elasticity of the wave spring (380) causes the distal assembly (350) to return to the state shown in FIG. 10A. At this point, the end effector (300) can be removed from the patient (PA).

[0049] In this example, a rapid increase in the fluid pressure within the balloon (302) causes deformation of the wave spring (380), and such deformation causes the cylindrical member (332) and the first cylindrical body (354) to move proximally relative to the remaining portion of the distal assembly (350), defining the clearance (392). Thus, the threshold fluid pressure for transitioning the distal assembly (350) from the sealed state (FIG. 10A) to the pressure-relieved state (FIG. 10B) is adjusted by the spring constant of the wave spring (380). By way of example only, the wave spring (380) may be configured to deform in response to a fluid pressure within the balloon (302) that exceeds a pressure threshold in the range of about 1.50 psi to about 8.00 psi, transitioning the state of the distal assembly (350). Alternatively, any other suitable pressure threshold may be indicated by the wave spring (380).

[0050] In the foregoing example, the corrugated spring (380) is used, but other suitable structures may be used. By way of example only, the corrugated spring (380) may be replaced with a coil spring or a Belleville washer spring. Other suitable types of elastic components that can be used in place of the corrugated spring (380) will be apparent to those skilled in the art in view of the teachings herein. It should also be understood that the O-ring (360) is merely optional, particularly when the distal surface of the first cylindrical body (354) abuts against the proximal surface of the distal annular member (352) to provide a direct substantial seal.

[0051] C. Example of the degassing process The foregoing examples of the tip assemblies (250, 350) are provided in the context of further pressure relief of the balloons (202, 302) during the operating phase when the balloons (202, 302) are shrinking. Additionally or alternatively, the pressure removal characteristics of the tip assemblies (250, 350) may also be beneficial in the context of balloons (202, 302) being degassed. This operating phase may occur before the balloons (202, 302) and tip assemblies (250, 350), etc. are inserted into the patient (PA). The degassing process may include flushing the balloons (202, 302) with saline or other liquid to purge air from the balloons (202, 302). As described herein, in a variant of the balloon (202, 302) lacking the tip assembly (250, 350), the purged air (and ultimately the purge liquid) may simply be discharged from the balloon (202, 302) through the openings (204, 304). However, in a variant of the balloon (202) including the tip assembly (250), the purged air (and ultimately the purge liquid) may leak through the passageway (290), the opening (264), and the gap (292) as described herein. Similarly, in a variant of the balloon (302) including the tip assembly (350), the purged air (and ultimately the purge liquid) may leak through the gaps (390, 392) as described herein.

[0052] Prior to inserting the end effector (200, 300) into the patient (PA), during the degassing process of the balloon (202, 302) having the tip assembly (250, 350), the physician (PH) can expose the balloon (202, 302) from the sheath (140), orient the balloon (202, 302) vertically, and activate the pump (44) to drive liquid from the fluid source (42) towards the balloon (202, 302). In some scenarios, the pump (44) is activated to drive liquid at a flow rate higher than the flow rate used during normal operation of the end effector (200, 300) when the end effector (200, 300) is disposed within the patient (PH). By way of example only, this relatively high flow rate can be in the range of about 60 mL / min to about 100 mL / min. The physician (PH) can observe the end effector (200, 300) while the pump (44) is operating and observe air bubbles leaking through the tip assembly (250, 350). Once the end effector (200, 300) reaches a point where liquid is flowing steadily through the tip assembly (250, 350) and all air appears to be effectively purged from the balloon (202, 302), the physician (PH) can orient the end effector (200, 300) horizontally to confirm that the degassing process was effective.

[0053] Once the physician (PH) is satisfied that the degassing process is effective, the physician (PH) can stop the activation of the pump (44) and contract the balloon (202, 302) by allowing all remaining fluid within the balloon (202, 302) to escape. The physician (PH) can further position the end effector (200, 300) within the sheath (140) such that the end effector (200, 300) is fully contained within the sheath (140) as previously described. The physician (PH) can then introduce the sheath (140), the end effector (200, 300), and the distal portion of the catheter (120) into the patient (PH) and perform the EP mapping and / or cardiac ablation procedure as previously described.

[0054] III. Examples of Combinations The following examples relate to various non-exhaustive ways in which the teachings of this specification can be combined or applied. It should be understood that the following examples are not intended to limit the scope of any claims that may be presented at any time in this application or in an application filed after this application. It is not intended to make any disclaimers. The following examples are for illustrative purposes only. The various teachings of this specification are considered to be capable of being configured and applied in many other ways. Also, in some variations, it is contemplated that certain features mentioned in the following examples may be omitted. Therefore, none of the aspects or features mentioned below should be considered important by the inventor or successors in interest of the inventor, unless explicitly stated otherwise at a later date. When claims containing additional features other than those mentioned below are presented in this application or in a later application related to this application, those additional features should not be assumed to have been added for any reason related to patentability.

Example

[0055] An apparatus comprising: (a) a catheter shaft assembly having a distal end; and (b) an end effector positioned at the distal end of the catheter shaft assembly, the end effector comprising: (i) a balloon having a proximal end and a distal end, defining an interior configured to receive fluid to inflate the balloon, and sized and configured to conform to a cardiovascular anatomical structure; (ii) one or more electrodes on the balloon; and (iii) a tip assembly at the distal end of the balloon, the tip assembly including a pressure relief valve configured to transition between a sealed state and a pressure-relieved state, wherein the pressure relief valve in the sealed state is configured to prevent fluid from leaking from the interior of the balloon through the pressure relief valve, and the pressure relief valve in the pressure-relieved state is configured to provide a path for fluid to leak from the interior of the balloon through the pressure relief valve.

Example

[0056] The device according to Example 1, wherein the pressure relief valve includes an elastic member configured to elastically bias the pressure relief valve into a closed state.

Example

[0057] The device according to Example 2, wherein the elastic member is configured to deform in response to a fluid pressure inside the balloon exceeding a pressure threshold value, and the elastic member is operable to shift the pressure relief valve from a closed state to a pressure relief state by the deformation of the elastic member.

Example

[0058] The device according to any one or more of Examples 2 to 3, wherein the elastic member has an annular shape.

Example

[0059] The device according to any one or more of Examples 2 to 4, wherein the elastic member includes an O-ring.

Example

[0060] The device according to any one or more of Examples 2 to 5, wherein the elastic member is configured to deform radially outwardly so as to be away from a central longitudinal axis defined by an end effector.

Example

[0061] The device according to any one or more of Examples 2 to 4, wherein the elastic member includes a wave spring.

Example

[0062] The device according to any one or more of Examples 2 to 4 or 7, wherein the elastic member is configured to deform along a central longitudinal axis defined by an end effector.

Example

[0063] The device according to any one or more of Examples 1 to 8, wherein the end effector further includes a cylindrical member at the distal end of the balloon, and the tip assembly is connected to the cylindrical member.

Example

[0064] The device according to Example 9, wherein the tip assembly includes a first cylindrical body disposed within the cylindrical member.

Example

[0065] The device according to Example 10, wherein the first cylindrical body is fixedly attached to the cylindrical member.

Example

[0066] The device according to any one or more of Examples 10 to 11, wherein the first cylindrical body includes at least one lateral opening configured to provide a path for fluid to leak out of the balloon.

Example

[0067] The device according to Example 12, further comprising an elastic member, the elastic member being operable to selectively seal at least one lateral opening, and the elastic member and at least one lateral opening cooperating to form a pressure relief valve.

Example

[0068] The device according to any one or more of Examples 10 to 11, wherein the tip assembly further includes a second cylindrical body, and the second cylindrical body is slidably disposed within the first cylindrical body.

Example

[0069] The device according to Example 14, wherein the first cylindrical body and the second cylindrical body are configured to define a leakage path between the inner diameter region of the first cylindrical body and the outer diameter of the second cylindrical body.

Example

[0070] The device according to Example 15, wherein an inner diameter region of the first cylindrical body defines a plurality of groove recesses, and the groove recesses are collectively configured to provide a leakage path.

Example

[0071] The device according to any one or more of Examples 14 to 16, wherein the first cylindrical body is operable to translate relative to the second cylindrical body, thereby transitioning the pressure relief valve from a sealed state to a pressure relief state.

Example

[0072] The device according to any one or more of Examples 10 to 17, wherein the tip assembly further includes a first flange positioned on the distal side of the cylindrical member.

Example

[0073] The device according to Example 18, wherein the tip assembly further includes a second flange positioned proximal to the cylindrical member.

Example

[0074] The device according to any one or more of Examples 1 to 19, comprising at least one electrode configured to sense the electrical potential within the tissue.

Example

[0075] The device according to any one or more of Examples 1 to 20, comprising at least one electrode configured to ablate the tissue.

Example

[0076] The device according to any one or more of Examples 1 to 21, wherein the balloon further includes a plurality of openings configured to allow the balloon to reach an inflated state while providing for leakage of fluid from the interior of the balloon.

Example

[0077] The device according to any one or more of Examples 1 to 22, further comprising a sheath slidably engaged with the catheter shaft assembly.

Example

[0078] The device according to Example 23, wherein the sheath is operable to translate relative to the catheter shaft assembly to selectively cover and uncover the balloon.

Example

[0079] The device according to any one or more of Examples 1 to 24, further comprising a position sensor operable to generate a signal indicative of the position of the end effector in three-dimensional space.

Example

[0080] The device according to any one or more of Examples 1 to 25, wherein the catheter shaft assembly includes an inner shaft extending through the interior of the balloon.

Example

[0081] The device according to Example 26, wherein the inner shaft is fixed to the tip assembly.

Example

[0082] The device according to any one or more of Examples 26 to 27, wherein the inner shaft defines a lumen and the tip assembly defines a distal opening, and the lumen and the distal opening are configured to accommodate passage of an instrument passing through the inner shaft and through the tip assembly.

Example

[0083] The device according to Example 28, wherein the lumen and the distal opening are fluidly isolated from the interior of the balloon.

Example

[0084] (a) A catheter shaft assembly having a distal end, and (b) an end effector positioned at the distal end of the catheter shaft assembly, the end effector including: (i) a balloon having a proximal end and a distal end, defining an interior configured to receive fluid and expand the balloon, sized and configured to conform to a cardiovascular anatomical structure; (ii) one or more electrodes on the balloon; and (iii) a tip assembly at the distal end of the balloon, the tip assembly including: (A) at least one opening, and (B) at least one elastic member, wherein at least one elastic member biases the tip assembly to provide the at least one opening in a closed state, thereby preventing fluid from leaking from the interior of the balloon through the at least one opening, and wherein the at least one elastic member is further configured to deform, thereby enabling fluid to leak from the interior of the balloon through the at least one opening in response to the fluid pressure inside the balloon exceeding a threshold value.

Example

[0085] The apparatus according to Example 30, wherein the elastic member is configured to selectively cover the at least one opening, and the elastic member is further configured to expand away from the at least one opening, thereby removing the cover from the at least one opening.

Example

[0086] The apparatus of Example 30, wherein the tip assembly further comprises: (a) a translator; and (b) a sealing member coupled to the translator and operable to selectively cover the at least one opening, and wherein the elastic member is arranged to elastically bias the translator to drive the sealing member to cover the at least one opening, and the elastic member is configured such that when the elastic member reaches a deformed state, the translator and the sealing member move, thereby enabling the cover by the sealing member to be removed from the at least one opening.

Example

[0087] (a) Positioning a balloon within the cardiovascular system; (b) Inflating the balloon with a fluid while the balloon is disposed within the cardiovascular system; and (c) Actuating a valve assembly at the distal end of the balloon such that fluid leaks from the interior of the balloon through the valve assembly.

Example

[0088] The act of actuating the valve assembly includes providing a fluid pressure within the interior of the balloon that exceeds a pressure threshold and actuating the valve assembly in response to the fluid pressure within the interior of the balloon that exceeds the pressure threshold, the method according to Example 33.

Example

[0089] The act of actuating the valve assembly includes deforming an elastic member to open a fluid path at the distal end of the balloon, the method according to any one or more of Examples 33 - 34.

Example

[0090] Before the act of actuating the valve assembly occurs, the inflated balloon leaks fluid through an opening formed in the balloon. The method according to any one or more of Examples 33 - 35.

Example

[0091] The method according to any one or more of Examples 33 - 36, further including contacting one or more electrodes on the balloon with tissue within the cardiovascular system.

Example

[0092] The method according to Example 37, further including picking up a potential from the tissue through at least one of the one or more electrodes that contact the tissue.

Example

[0093] The method according to any one or more of Examples 37 to 38, further comprising ablating the tissue through at least one of one or more electrodes that contact the tissue.

Examples

[0094] The method according to any one or more of Examples 33 to 39, further comprising contacting the inflated balloon with the sheath, causing a rapid increase in the fluid pressure inside the balloon due to the contact between the inflated balloon and the sheath, and actuating the valve assembly due to the rapid increase in the fluid pressure.

[0095] IV. Others Any of the instruments described herein may be cleaned and sterilized before and / or after treatment. In one sterilization technique, the device is placed in a closed and sealed container such as a plastic or TYVEK bag. The container and the device may then be placed in a radiation field that can penetrate the container, such as gamma rays, X-rays, or high-energy electron beams. The radiation can kill bacteria on the device and inside the container. The sterilized device may then be stored in a sterile container for later use. The device may also be sterilized using any other technique known in the art, including but not limited to beta or gamma rays, ethylene oxide, hydrogen peroxide, peracetic acid, and vapor phase sterilization (with or without using gas plasma), or steam.

[0096] It should be understood that any of the examples described herein may include various other features in addition to or instead of those described above. By way of example only, any of the examples described herein may also include one or more of the various features disclosed in any of the various references incorporated herein by reference.

[0097] It should be understood that any one or more of the teachings, expressions, embodiments, examples, etc. described in this specification can be combined with any one or more of the other teachings, expressions, embodiments, examples, etc. described in this specification. Therefore, the above-mentioned teachings, expressions, embodiments, examples, etc. should not be considered independently of each other. In light of the teachings of this specification, various suitable ways of combining the teachings of this specification will be readily apparent to those skilled in the art. Such modifications and variations are intended to be included within the scope of the "claims".

[0098] Any patent, publication, or other disclosure content that is referred to as incorporated by reference herein is to be understood as being incorporated herein only to the extent that the incorporated content is not in conflict with the current definitions, opinions, or other disclosure content described in this disclosure, either in whole or in part. By itself, and to the extent necessary, the disclosure content clearly described herein shall prevail over any conflicting descriptions incorporated herein by reference. Any content, or portions thereof, that is referred to as being incorporated by reference herein but is in conflict with the current definitions, opinions, or other disclosure content described in this specification shall be incorporated only to the extent that no conflict arises between the incorporated content and the current disclosure content.

[0099] Although various variations of the present invention have been illustrated and described, further applications of the methods and systems described in this specification can be realized by appropriate modifications by those skilled in the art without departing from the scope of the present invention. Some of such possible modifications have been described, but other modifications will also be apparent to those skilled in the art. For example, the above-described examples, variations, geometries, materials, dimensions, ratios, processes, etc. are illustrative and not essential. Therefore, the scope of the present invention should be considered from the perspective of the following claims and is to be understood as not being limited to the details of the structures and operations shown and described in this specification and the drawings.

[0100] 〔Embodiment〕 (1) (a) A catheter shaft assembly having a distal end, and (b) An end effector positioned at the distal end of the catheter shaft assembly, (i) A balloon having a proximal end and a distal end, defining an interior configured to receive fluid to inflate the balloon, sized and configured to conform to a cardiovascular anatomical structure, (ii) One or more electrodes on the balloon, (iii) A tip assembly at the distal end of the balloon, the tip assembly including a pressure relief valve configured to transition between a sealed state and a pressure relieved state, An end effector including Comprising, The pressure relief valve in the sealed state is configured to prevent fluid from leaking from the interior of the balloon through the pressure relief valve, The pressure relief valve in the pressure relieved state is configured to provide a path for fluid to leak from the interior of the balloon through the pressure relief valve, Device. (2) The device according to embodiment 1, wherein the pressure relief valve includes an elastic member configured to elastically bias the pressure relief valve to the sealed state. (3) The elastic member is configured to deform in response to a fluid pressure inside the balloon exceeding a pressure threshold, The elastic member is operable to transition the pressure relief valve from the sealed state to the pressure relieved state by the deformation of the elastic member, The device according to embodiment 2. (4) The device according to embodiment 1, wherein the end effector further includes a cylindrical member at the distal end of the balloon, The tip assembly is connected to the cylindrical member. The device according to embodiment 1. (5) The device according to embodiment 4, wherein the tip assembly includes a first cylindrical body disposed within the cylindrical member.

[0101] (6) The first cylindrical body includes at least one lateral opening, and the at least one lateral opening is configured to provide a path for fluid leakage from the interior of the balloon. The device according to embodiment 5. (7) The device further comprises an elastic member, wherein the elastic member is operable to selectively seal the at least one lateral opening, and the elastic member and the at least one lateral opening cooperate to form the pressure relief valve. The device according to embodiment 6. (8) The tip assembly further comprises a second cylindrical body, wherein the second cylindrical body is slidably disposed within the first cylindrical body. The device according to embodiment 5. (9) The device according to embodiment 8, wherein the first cylindrical body and the second cylindrical body are configured to define a leakage path between an inner diameter region of the first cylindrical body and an outer diameter of the second cylindrical body. (10) The inner diameter region of the first cylindrical body defines a plurality of groove recesses, and the groove recesses are collectively configured to provide the leakage path. The device according to embodiment 9.

[0102] (11) The device according to embodiment 8, wherein the first cylindrical body is operable to translate relative to the second cylindrical body, thereby transitioning the pressure relief valve from the sealed state to the pressure relief state. (12) The device according to embodiment 5, wherein the tip assembly further comprises a first flange positioned on the distal side of the cylindrical member. (13) The device according to embodiment 12, wherein the tip assembly further comprises a second flange positioned on the proximal side of the cylindrical member. (14) The device according to embodiment 1, wherein the one or more electrodes include at least one electrode configured to sense an electric potential within tissue. (15) The apparatus according to embodiment 1, wherein the one or more electrodes include at least one electrode configured to ablate tissue.

[0103] (16) The balloon further includes a plurality of openings, wherein the openings are configured to allow the balloon to reach an inflated state while still providing leakage of fluid from the interior of the balloon. The apparatus according to embodiment 1. (17) The apparatus according to embodiment 1, wherein the catheter shaft assembly includes an inner shaft extending through the interior of the balloon and fixed to the tip assembly. (18) The inner shaft defines a lumen, the tip assembly defines a distal opening, wherein the lumen and the distal opening are configured to accommodate passage of an instrument through the inner shaft and through the tip assembly, and the lumen and the distal opening are fluidly isolated from the interior of the balloon. The apparatus according to embodiment 17. (19) (a) A catheter shaft assembly having a distal end, and (b) An end effector positioned at the distal end of the catheter shaft assembly, the end effector comprising: (i) A balloon having a proximal end and a distal end, defining an interior configured to receive fluid to inflate the balloon, and sized and configured to conform to a cardiovascular anatomical structure; (ii) One or more electrodes on the balloon; and (iii) A tip assembly at the distal end of the balloon, the tip assembly comprising: (A) At least one opening; and (B) At least one elastic member. The tip assembly comprising; An end effector comprising; Comprising; The at least one elastic member biases the tip assembly to provide the at least one opening in a closed state, thereby preventing fluid from leaking from the interior of the balloon through the at least one opening. The at least one elastic member is further configured to deform, such that in response to the fluid pressure inside the balloon exceeding a threshold value, fluid is allowed to leak from the interior of the balloon through the at least one opening. Device. (20) (a) positioning the balloon within the cardiovascular system; (b) inflating the balloon with fluid while the balloon is disposed within the cardiovascular system; (c) actuating the valve assembly at the distal end of the balloon such that fluid leaks from the interior of the balloon through the valve assembly. Method comprising.

Claims

1. (a) A catheter shaft assembly having a distal end, and (b) An end effector positioned at the distal end of the catheter shaft assembly, comprising (i) A balloon having a proximal end and a distal end, defining an interior configured to receive fluid to inflate the balloon, sized and configured to conform to a cardiovascular anatomical structure, the balloon; (ii) One or more electrodes on the balloon; (iii) A tip assembly at the distal end of the balloon, the tip assembly including a pressure relief valve configured to transition between a sealed state and a pressure relieved state; An end effector comprising; Comprising; The pressure relief valve in the sealed state is configured to prevent fluid from leaking from the interior of the balloon through the pressure relief valve; The pressure relief valve in the pressure relieved state is configured to provide a path for fluid to leak from the interior of the balloon through the pressure relief valve; The end effector further includes a cylindrical member at the distal end of the balloon, the tip assembly being coupled to the cylindrical member; The tip assembly includes a first cylindrical body disposed within the cylindrical member; The first cylindrical body includes at least one lateral opening configured to provide a path for leakage of fluid from the interior of the balloon; The end effector further comprises an elastic member operable to selectively seal the at least one lateral opening, the elastic member and the at least one lateral opening cooperating to form the pressure relief valve, a device.

2. The device according to claim 1, wherein the elastic member is configured to elastically bias the pressure relief valve to the sealed state.

3. The elastic member is configured to deform in response to a fluid pressure inside the balloon exceeding a pressure threshold; The elastic member is operable to transition the pressure relief valve from the sealed state to the pressure relieved state by deformation of the elastic member; The device according to claim 2.

4. (a) A catheter shaft assembly having a distal end, and (b) An end effector positioned at the distal end of the catheter shaft assembly, (i) A balloon having a proximal end and a distal end, defining an interior configured to receive fluid to inflate the balloon, sized and configured to conform to a cardiovascular anatomical structure, the balloon; (ii) One or more electrodes on the balloon; (iii) A tip assembly at the distal end of the balloon, the tip assembly including a pressure relief valve configured to transition between a sealed state and a pressure-relieved state; An end effector comprising; Comprising; The pressure relief valve in the sealed state is configured to prevent fluid from leaking from the interior of the balloon through the pressure relief valve; The pressure relief valve in the pressure-relieved state is configured to provide a path for fluid to leak from the interior of the balloon through the pressure relief valve; The end effector further includes a cylindrical member at the distal end of the balloon, and the tip assembly is coupled to the cylindrical member; The tip assembly includes a first cylindrical body disposed within the cylindrical member and a second cylindrical body, the second cylindrical body being slidably disposed within the first cylindrical body; The first cylindrical body and the second cylindrical body are configured to define a leakage path between an inner diameter region of the first cylindrical body and an outer diameter of the second cylindrical body.

5. The inner diameter region of the first cylindrical body defines a plurality of groove recesses; The groove recesses are collectively configured to provide the leakage path; The device according to claim 4.

6. The first cylindrical body is operable to translate relative to the second cylindrical body, thereby transitioning the pressure relief valve from the sealed state to the pressure-relieved state, the device according to claim 4.

7. (a) A catheter shaft assembly having a distal end, and (b) An end effector positioned at the distal end of the catheter shaft assembly, (i) A balloon having a proximal end and a distal end, defining an interior configured to receive fluid to inflate the balloon, sized and configured to conform to a cardiovascular anatomical structure, the balloon; (ii) One or more electrodes on the balloon; (iii) A tip assembly at the distal end of the balloon, the tip assembly including a pressure relief valve configured to transition between a sealed state and a pressure-relieved state. An end effector, including Comprising The pressure relief valve in the sealed state is configured to prevent fluid from leaking out of the interior of the balloon through the pressure relief valve. The pressure relief valve in the pressure-relieved state is configured to provide a path for fluid to leak out of the interior of the balloon through the pressure relief valve. An apparatus, wherein the one or more electrodes include at least one electrode configured to sense a potential within tissue. **Claim 8**: (a) A catheter shaft assembly having a distal end, and (b) An end effector positioned at the distal end of the catheter shaft assembly, the end effector comprising: (i) A balloon having a proximal end and a distal end, defining an interior configured to receive fluid to inflate the balloon, sized and configured to conform to a cardiovascular anatomical structure. (ii) One or more electrodes on the balloon; (iii) A tip assembly at the distal end of the balloon, the tip assembly including a pressure relief valve configured to transition between a sealed state and a pressure-relieved state. An end effector, including Comprising The pressure relief valve in the sealed state is configured to prevent fluid from leaking out of the interior of the balloon through the pressure relief valve. The pressure relief valve in the pressure-relieved state is configured to provide a path for fluid to leak out of the interior of the balloon through the pressure relief valve. An apparatus, wherein the one or more electrodes include at least one electrode configured to ablate tissue. **Claim 9**: (a) A catheter shaft assembly having a distal end, and (b) An end effector positioned at the distal end of the catheter shaft assembly, the end effector comprising: (i) A balloon having a proximal end and a distal end, defining an interior configured to receive fluid to inflate the balloon, sized and configured to conform to a cardiovascular anatomical structure. (ii) One or more electrodes on the balloon; (iii) A tip assembly at the distal end of the balloon, the tip assembly including a pressure relief valve configured to transition between a sealed state and a pressure-relieved state. An end effector, including Comprising The pressure relief valve in the sealed state is configured to prevent fluid from leaking from the interior of the balloon through the pressure relief valve. The pressure relief valve in the pressure-relieved state is configured to provide a path for fluid to leak from the interior of the balloon through the pressure relief valve. The balloon further includes a plurality of openings. The openings are configured to allow the balloon to reach an inflated state while still providing for leakage of the fluid from the interior of the balloon. A device. **Claim 10**: (a) A catheter shaft assembly having a distal end, and (b) An end effector positioned at the distal end of the catheter shaft assembly, the end effector comprising: (i) A balloon having a proximal end and a distal end, defining an interior configured to receive fluid and inflate the balloon, sized and configured to conform to a cardiovascular anatomical structure; (ii) One or more electrodes on the balloon; (iii) A tip assembly at the distal end of the balloon, the tip assembly including a pressure relief valve configured to transition between a sealed state and a pressure-relieved state. An end effector, including Comprising The pressure relief valve in the sealed state is configured to prevent fluid from leaking from the interior of the balloon through the pressure relief valve. The pressure relief valve in the pressure-relieved state is configured to provide a path for fluid to leak from the interior of the balloon through the pressure relief valve. The catheter shaft assembly includes an inner shaft extending through the interior of the balloon and fixed to the tip assembly. A device. **Claim 11** The inner shaft defines a lumen. The tip assembly defines a distal opening. The lumen and the distal opening are configured to accommodate the passage of an instrument through the inner shaft and through the tip assembly. The lumen and the distal opening are fluidly isolated from the interior of the balloon. The apparatus according to claim 10.

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