Locking the Catheter Assembly

Abstract

A medical device for use in a catheter assembly including an elongate catheter coaxially disposed within a sheath is disclosed. The medical device includes a deformable tube having a proximal end, a distal end, an outer wall having an outer diameter, and an inner wall forming an axial lumen. The distal end is attached to the sheath, and the proximal end receives the catheter within the lumen. The medical device also includes opposing paddles disposed relative to the outer wall, each having a generally planar locking region disposed relative to the outer wall at the outer diameter, the locking surface being tangential to the deformable tube. The opposing paddles are movable laterally relative to the deformable tube at locations along the outer diameter.

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates generally to medical systems and methods that use catheter assemblies, and more particularly to medical systems and methods for locking a catheter assembly in place within a patient during a procedure. [Background technology]

[0002] Medical devices in the form of catheter systems are widely used in various medical procedures to access remote anatomical locations or deploy therapeutic devices. For example, electrophysiology procedures involve navigating a catheter assembly into the heart and tracking its position relative to the heart. Catheter ablation is a minimally invasive electrophysiology procedure for treating various cardiac disorders, such as supraventricular arrhythmias and ventricular arrhythmias. Catheter-based cardiac mapping is another minimally invasive electrophysiology procedure for identifying temporal and spatial electrical potentials during cardiac rhythms. Catheter assemblies, including those used in electrophysiology procedures, may include multiple catheter elements, such as a catheter, a sheath, a guidewire, and a needle. For example, the catheter assembly may include a long catheter within a long sheath. Access to a patient's heart can be achieved through a blood vessel (e.g., a peripheral artery or vein) via a large-bore sheath or introducer sheath. Once vascular access is obtained, the catheter assembly may be navigated into the patient's heart, and the catheter may be selectively deployed from within the sheath. Summary of the Invention

[0003] Example 1 provides a medical device for use in a catheter assembly including an elongate catheter coaxially disposed within a sheath. The medical device includes a deformable tube having a proximal end, a distal end, an outer wall having an outer diameter, and an inner wall forming an axial lumen, the distal end configured to be attached to the sheath and the proximal end configured to receive a catheter within the lumen. The medical device also includes a plurality of opposing paddles disposed relative to the outer wall, each of the plurality of opposing paddles having a generally planar locking region configured to be disposed against the outer wall at the outer diameter, the locking surface disposed tangentially relative to the deformable tube, and the plurality of opposing paddles being movable laterally relative to the deformable tube at a location along the outer diameter. The medical device has a first compressed state in which the catheter is coaxially disposed within the sheath and the plurality of opposing paddles are releasably urged against the deformable tube at an outer diameter to collapse the deformable tube and hold the catheter in place relative to the sheath and the deformable tube, with the collapsed deformable tube forming an elongate opening along the inner wall and the catheter. The medical device has a second compressed state in which the catheter is not coaxially disposed within the sheath and is detached from the deformable tube and the plurality of opposing paddles are releasably urged against the deformable tube at an outer diameter to collapse the deformable tube and seal the lumen.

[0004] In Example 2, the medical device of Example 1 has a catheter assembly incorporated into the medical device. In Example 3, the medical device of any of Examples 1 and 2, wherein the catheter assembly is configured to perform irreversible electroporation.

[0005] In Example 4, the medical device of any of Examples 1 to 3 further comprises a nominal state in which the catheter is coaxially disposed within the sheath and is movable relative to the sheath and the deformable tube.

[0006] In Example 5, in the medical device of Example 4, the inner wall comprises a circular cross section in the reference state. In Example 6, in the medical device of Example 5, the locking region includes a height, the inner wall includes a circumference, and the height is at least half of the circumference.

[0007] In Example 7, the medical device of any of Examples 4-5, wherein the inner wall comprises an elliptical cross-section in the first compressed state. In Example 8, the medical device of any of Examples 1 to 7, the plurality of opposing paddles includes two opposing paddles.

[0008] In Example 9, the locking regions in the medical device of Example 8 are generally parallel to one another. In Example 10, the medical device of any of Examples 1-9, wherein the locking region forms an overlapping region on the deformable tube.

[0009] In Example 11, the medical device of Example 10, wherein the inner wall associated with the overlap region sandwiches the catheter in the first compressed state. In Example 12, the medical device of any of Examples 10-11, wherein the inner wall associated with the overlap region seals the lumen in the second compressed state.

[0010] In Example 13, in the medical device of any of Examples 10 to 12, the proximal end and the distal end are spaced apart from the overlap region. In Example 14, in the medical device of any of Examples 1 to 13, the proximal end includes a proximal hub configured to guide the catheter into the lumen, and the distal end includes a distal hub configured to be attached to the sheath.

[0011] In Example 15, the medical device of any of Examples 1 to 14 further comprises a drive mechanism operably coupled to the plurality of opposing paddles, the drive mechanism configured to move the plurality of opposing paddles laterally relative to the deformable tube.

[0012] Example 16 provides a medical device for use in a catheter assembly including an elongate catheter coaxially disposed within a sheath. The medical device includes a deformable tube having a proximal end, a distal end, an outer wall having an outer diameter, and an inner wall forming an axial lumen, the distal end configured to be attached to the sheath and the proximal end configured to receive the catheter within the lumen. The medical device also includes a plurality of opposing paddles disposed relative to the outer wall, each of the plurality of opposing paddles having a generally planar locking region configured to be disposed relative to the outer wall at the outer diameter, the locking surface being disposed tangentially relative to the deformable tube, and the plurality of opposing paddles being movable laterally relative to the deformable tube at a location along the outer diameter. The medical device has a first compressed state in which the catheter is coaxially disposed within the sheath and the plurality of opposing paddles releasably press against the deformable tube at the outer diameter to collapse the deformable tube and hold the catheter in place relative to the sheath and the deformable tube, the collapsed deformable tube forming an elongate opening along the inner wall and the catheter. The medical device has a second compressed state in which the catheter is not coaxially disposed within the sheath and is removed from the deformable tube, and the multiple opposing paddles are releasably pressed against the deformable tube at the outer diameter to collapse the deformable tube and seal the lumen.

[0013] In Example 17, the medical device of Example 16 further comprises a reference state in which the catheter is coaxially disposed within the sheath and the catheter is movable relative to the sheath and the deformable tube.

[0014] In Example 18, the medical device of Example 17, wherein the inner wall comprises a circular cross section in the reference state. In Example 19, in the medical device of Example 18, the locking region includes a height, the inner wall includes a circumference, and the height is at least half of the circumference.

[0015] In Example 20, the medical device of Example 18, wherein the inner wall comprises an elliptical cross-section in the first compressed state. In Example 21, the medical device of Example 16, wherein the locking region forms an overlap region on the deformable tube, and the proximal and distal ends are spaced apart from the overlap region.

[0016] In Example 22, the medical device of Example 16 further includes a drive mechanism operably coupled to the plurality of opposing paddles, the drive mechanism configured to move the plurality of opposing paddles laterally relative to the deformable tube.

[0017] In Example 23, the medical device of Example 16, wherein the proximal end includes a proximal hub configured to guide the catheter into the lumen, and the distal end includes a distal hub configured to be attached to the sheath.

[0018] In Example 24, the medical device of Example 16, wherein the plurality of opposing paddles includes two opposing paddles, and the locking regions are generally parallel to each other. In Example 25, a medical system includes a catheter assembly having an elongate catheter coaxially positionable within a sheath, and a locking mechanism. The locking mechanism includes a deformable tube and a plurality of opposing paddles. The deformable tube has a proximal end, a distal end, an outer wall having an outer diameter, and an inner wall forming an axial lumen, the distal end configured to be attached to the sheath, and the proximal end configured to receive a catheter within the lumen. The plurality of opposing paddles are disposed relative to the outer wall, each of the plurality of opposing paddles having a generally planar locking region configured to be disposed relative to the outer wall at the outer diameter, the locking surface being disposed tangentially relative to the deformable tube, and the plurality of opposing paddles are movable laterally relative to the deformable tube at a position along the outer diameter. The medical system has a first compressed state in which the catheter is coaxially disposed within the sheath and the plurality of opposing paddles releasably press against the deformable tube at an outer diameter to collapse the deformable tube and hold the catheter in place relative to the sheath and the deformable tube, with the collapsed deformable tube forming an elongated opening along the inner wall and the catheter, and a second compressed state in which the catheter is not coaxially disposed within the sheath and is detached from the deformable tube and the plurality of opposing paddles releasably press against the deformable tube at an outer diameter to collapse the deformable tube and seal the lumen.

[0019] In Example 26, the medical system of Example 25, wherein the catheter assembly is configured to perform irreversible electroporation. In Example 27, the medical system of Example 25 further comprises a reference state in which the catheter is coaxially disposed within the sheath and the catheter is movable relative to the sheath and the deformable tube.

[0020] In Example 28, the medical system of Example 25 further includes a drive mechanism operably coupled to the plurality of paddles, the drive mechanism configured to laterally move the plurality of opposing paddles relative to the deformable tube.

[0021] Example 29 describes a method for use in a catheter assembly having an elongate catheter coaxially positionable within a sheath. A medical device is provided. The medical device includes a deformable tube having a proximal end, a distal end, an outer wall having an outer diameter, and an inner wall forming an axial lumen, the distal end configured to be attached to the sheath, and the proximal end configured to receive a catheter within the lumen. The medical device also includes a plurality of opposing paddles disposed against the outer wall, each of the plurality of opposing paddles having a generally planar locking region configured to be disposed against the outer wall at the outer diameter, the locking surface being disposed tangentially relative to the deformable tube, and the plurality of opposing paddles being movable laterally relative to the deformable tube at a position along the outer diameter. The catheter is coaxially positioned within the sheath. The plurality of opposing paddles releasably press against the deformable tube at the outer diameter to collapse the deformable tube and hold the catheter in place relative to the sheath and the deformable tube, with the collapsed deformable tube forming an elongate opening along the inner wall and the catheter. The catheter is removed from the deformable tube, and a plurality of opposing paddles are releasably pressed against the deformable tube at its outer diameter to collapse the deformable tube and seal the lumen.

[0022] In Example 30, the method of Example 29 further comprises flowing a fluid through the elongated opening. In Example 31, in the method of Example 30, preparing the medical device includes preparing a deformable tube having an inner wall with a circular cross-section, and holding the catheter in place relative to the sheath includes ellipsing the cross-section to form an elongated opening.

[0023] In Example 32, the method of Example 29 includes forming an overlap region on the deformable tube. In Example 33, in the method of Example 32, holding the catheter in place relative to the sheath includes pinching the catheter with an inner wall associated with the overlap region.

[0024] In Example 34, in the method of Example 32, collapsing the deformable tube to seal the lumen includes collapsing the deformable tube at the overlap region. In Example 35, in the method of Example 29, preparing the medical device includes preparing a proximal hub attached to the proximal end, and the method further includes guiding the catheter into the lumen through the proximal hub.

[0025] While multiple embodiments are disclosed, still other embodiments of the present disclosure will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the present disclosure. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. [Brief explanation of the drawings]

[0026] [Figure 1] FIG. 1 illustrates an exemplary clinical environment having an exemplary electrophysiological system for treating a patient and for treating the patient's heart. [Figure 2] FIG. 2 is a schematic diagram illustrating an exemplary catheter assembly locking mechanism for use in the exemplary electrophysiology system of FIG. 1. [Figure 3A] 3A-3C are schematic diagrams of various exemplary states of an exemplary cross section of the exemplary catheter assembly locking mechanism of FIG. 2. [Figure 3B] 3A-3C are schematic diagrams of various exemplary states of an exemplary cross section of the exemplary catheter assembly locking mechanism of FIG. 2. [Figure 3C] 3A-3C are schematic diagrams of various exemplary states of an exemplary cross section of the exemplary catheter assembly locking mechanism of FIG. 2. [Figure 4A]3B is a perspective view of an exemplary catheter assembly locking mechanism for use in the exemplary electrophysiology system of FIG. 1 in the state of FIG. 3A. [Figure 4B] 3C is a perspective view of an exemplary catheter assembly locking mechanism for use in the exemplary electrophysiology system of FIG. 1 in the state of FIG. 3B. [Figure 4C] 3D is a perspective view of an exemplary catheter assembly locking mechanism for use in the exemplary electrophysiology system of FIG. 1 in the state of FIG. 3C. [Figure 5A] FIG. 4B is a top view of an exemplary catheter assembly locking mechanism in the state of FIG. 4A. [Figure 5B] FIG. 4C is a top view of an exemplary catheter assembly locking mechanism in the state of FIG. 4B. [Figure 5C] FIG. 4D is a top view of an exemplary catheter assembly locking mechanism in the state of FIG. 4C. [Figure 6A] 5B is a top cross-sectional view of an exemplary catheter assembly locking mechanism in the state of FIG. 5A. FIG. [Figure 6B] 5C is a top cross-sectional view of an exemplary catheter assembly locking mechanism in the state of FIG. 5B. [Figure 6C] 5D is a top cross-sectional view of an exemplary catheter assembly locking mechanism in the state of FIG. 5C. [Figure 7A] FIG. 4B is a cross-sectional side view of an exemplary catheter assembly locking mechanism in the state of FIG. 4A. [Figure 7B] FIG. 4C is a cross-sectional side view of an exemplary catheter assembly locking mechanism in the state of FIG. 4B. [Figure 7C] FIG. 4D is a cross-sectional side view of an exemplary catheter assembly locking mechanism in the state of FIG. 4C. DETAILED DESCRIPTION OF THE INVENTION

[0027] While the present disclosure is susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are described in detail below. The intention, however, is not to limit the disclosure to the particular embodiments described. Rather, the disclosure is intended to cover all modifications, equivalents, and alternatives falling within the scope of the present disclosure as defined by the appended claims.

[0028] For purposes of promoting an understanding of the principles of the present disclosure, reference will be made to the examples illustrated in the drawings described below. The illustrative examples disclosed herein are not intended to be exhaustive or to limit the disclosure to the precise form disclosed in the following detailed description. Rather, these exemplary embodiments were chosen and described so that those skilled in the art might use their teachings. The use of multiple (e.g., all) features across all examples would not be beyond the scope of the present disclosure. Thus, no figure should be interpreted as having any dependency or requirement relating to any single component or combination of components shown. In addition, various components shown in the figures may, in some examples, be combined with various of the other components shown (or components not shown), all of which are considered to be within the scope of the present disclosure.

[0029] Examples of electrophysiology procedures and systems using catheter assemblies, including electroanatomical mapping systems and cardiac ablation systems, are described in this disclosure along with electrophysiology testing and ablation systems for illustrative purposes. Ablation procedures are used to treat many different conditions in patients. Ablation can be used to treat cardiac arrhythmias, benign tumors, cancerous tumors, and to control bleeding during surgery. Ablation is typically achieved by thermal ablation techniques, including radiofrequency (RF) ablation and cryoablation. In RF ablation, a probe is inserted into the patient, and radiofrequency waves are transmitted through the probe to the surrounding tissue. The radiofrequency waves generate heat, which destroys the surrounding tissue and cauterizes blood vessels. In cryoablation, a hollow needle or cryoprobe is inserted into the patient, and a low-temperature, heat-conductive fluid is circulated through the probe, freezing and killing the surrounding tissue. RF ablation and cryoablation techniques can indiscriminately kill tissue through necrosis, which can damage or kill other healthy tissue, such as tissue in the esophagus, phrenic nerve cells, and tissue in the coronary arteries.

[0030] Another ablation technique uses electroporation. In electroporation, or electropermeabilization, an electric field is applied to cells to increase the permeability of the cell membrane. Electroporation can be reversible or irreversible, depending on the strength and duration of the electric field. If electroporation is reversible, the temporarily increased permeability of the cell membrane can be used to introduce chemicals, drugs, or deoxyribonucleic acid (DNA) into the cells prior to cellular healing and recovery. Tissue recovery can occur over minutes, hours, or days after ablation is complete. If electroporation is irreversible, the affected cells die, for example, via a form of cell death (e.g., programmed cell death, possibly via apoptosis, or traumatic cell death, e.g., via necrosis).

[0031] Irreversible electroporation can be used as a non-thermal ablation technique. Irreversible electroporation uses a train of brief, high-voltage pulses to generate an electric field strong enough to kill cells. For cardiac tissue ablation, irreversible electroporation can be a relatively safe and effective alternative to the indiscriminate killing of thermal ablation techniques such as RF ablation and cryoablation. Irreversible electroporation can be used to kill target tissue, such as myocardial tissue, by selecting an electric field strength and duration that is ineffective at permanently killing other cells or tissues, such as non-target myocardial tissue, red blood cells, vascular smooth muscle tissue, endothelial tissue, and nerve cells.

[0032] Such exemplary electrophysiology procedures often involve guiding a catheter assembly into a patient's heart. Access to the patient's heart may be achieved through a blood vessel via an introducer sheath. Once vascular access is obtained, the catheter assembly may be guided into the patient's heart. Examples of other procedures that use large-diameter sheaths include transcatheter aortic valve replacement, endovascular aneurysm repair, and mechanical circulatory assist devices that employ large-diameter access for deployment. However, current use of large-diameter sheaths involves issues related to air ingress during device introduction and removal. To address the air ingress issue, clinicians have used informal methods such as high-flow flushing, suction, and water baths to reduce the risk of complications, including air embolism.

[0033] FIG. 1 illustrates an exemplary clinical environment 10 for treating a patient 20 (e.g., for treating a heart 30 of the patient 20) using an electrophysiology system 50 according to the present disclosure. The electrophysiology system 50 includes an ablation catheter system 60 and an electroanatomical mapping (EAM) system 70. The exemplary catheter system 60 includes an elongate catheter assembly 100, in this example including a catheter 105 within the sheath, an introducer sheath 110, a locking mechanism 120, and a console 130. The electroporation console 130 is configured to control aspects of the electroporation catheter system 60. Additionally, the catheter system 60 includes various connection elements (e.g., cables) that operably connect components of the catheter system 60 to each other and to components of the EAM system 70. Generally, the EAM system 70 includes a localization field generator 80, a mapping and navigation controller 90, and a display 92. The EAM system 70 is operable to track the positions of various components of the catheter system 60 and generate a high-fidelity three-dimensional electroanatomical map of the heart, including portions of the heart (e.g., a heart chamber of interest or other structure of interest (e.g., the sinoatrial node or atrioventricular node)), from a catheter or probe equipped with sensing electrodes. In one illustrative example, the EAM system 70 may include a RHYTHMIA™ HDx mapping system sold by Boston Scientific Corporation. One illustrative probe is the INTELLAMAP ORION™ mapping catheter sold by Boston Scientific Corporation. The clinical environment 10 may also include additional equipment (e.g., imaging equipment 94 (represented by a C-arm)) and various controller elements (e.g., a foot controller 96) configured to enable an operator to control various aspects of the electrophysiology system 50.Clinical environment 10 may have other components and arrangements of components not shown in FIG.

[0034] The introducer sheath 110 is operable to provide a delivery conduit through which the catheter assembly 100 may be deployed to a specific target site within the patient's heart 30. Access to the patient's heart may be achieved through a blood vessel (e.g., a peripheral artery or vein). Once vascular access is gained, the catheter assembly 100 may be guided within the patient's heart (e.g., within a chamber of the heart). The locking mechanism may be a separate component of the catheter system 60 or may be a feature of another component, such as the introducer sheath 110 or other component.

[0035] The exemplary catheter 105 includes an elongate catheter shaft and a distal end configured to be deployed near a target tissue (e.g., within a patient's heart chamber). The distal end may include a basket, balloon, spline, structured tip, or other electrode deployment mechanism. The electrode deployment mechanism includes an electrode assembly or array with electrodes for delivering therapy or sensing effects within the heart. For example, the electrode assembly may include multiple spaced electrodes, multiple sets of spaced electrodes, or multiple groups of spaced electrodes. In some examples, electrodes (e.g., multiple spaced electrodes) may be deployed on the catheter shaft in addition to or instead of electrodes on the electrode deployment mechanism. In one example, the multiple electrodes may be formed from a conductive solid surface biocompatible material and spaced apart via an insulator. Each of the multiple electrodes is electrically connected to a corresponding elongate lead conductor extending along the shaft to the catheter proximal end. The multiple lead conductors may be electrically connected to a plug in the proximal region of the catheter 105 (e.g., a plug configured to be mechanically and electrically connectable to the console 130), for example, directly or via an intermediate electrical conductor such as cable wiring.

[0036] In one example, console 130 is configured to provide electrical signals (e.g., multiple simultaneous or time-spaced electrical signals) to catheter 105 electrically connected along lead conductors to spaced electrodes. In one example of an ablation catheter, the multiple spaced electrodes are configured to generate selected electrical signals near the target tissue based on the electrical signals from console 130 to perform ablation.

[0037] The ablation catheter system 60 is configured to deliver energy to target tissue within a patient's heart 30 to cause cell death in the tissue, e.g., to render the tissue unable to conduct electrical signals. An elongated catheter assembly (e.g., catheter assembly 100) may include multiple coaxially arranged catheter elements. For example, the catheter elements (e.g., sheaths or catheters) define a longitudinal axis passing through the cross-sectional centroid of the catheter element (e.g., the cross-sectional centroid of the catheter shaft or the cross-sectional centroid of the sheath lumen). Multiple coaxially arranged catheter elements are arranged such that one catheter element is positioned within another catheter element such that the longitudinal axes of each catheter element generally follow the same three-dimensional curve or path to their distal-most point.

[0038] The catheter element may include a first catheter element (e.g., an elongate sheath) or an outer catheter element in the catheter assembly 100. Additionally, the catheter element may include a second catheter element (e.g., an elongate catheter) or an inner catheter element in the catheter assembly 100. The first catheter element includes an elongate lumen, and the second catheter element is disposed within the lumen. For example, the outer diameter of the catheter is selected to be smaller than the inner diameter of the lumen in the sheath. The first and second catheter elements are movable relative to each other along the longitudinal axis. For example, the distal end of the catheter can be manipulated to extend from the distal tip of the sheath, or the distal tip of the sheath can be retracted from the distal end of the catheter, to expose the deployment mechanism, including expanding the basket. Additionally, the distal end of the catheter can be retracted from the distal tip of the sheath in the assembly 100, to retract the deployment mechanism, retract the electrodes, etc.

[0039] A selected electric field can be generated using electrodes to perform electroporation. By selecting a first electrode or a first group of electrodes as an anode and a different second electrode or group of electrodes as a cathode, an electric field can be generated between the anode and the cathode based on a signal (e.g., a pulse) provided to the electrodes from the electroporation console 130. The console 130 delivers electric pulses of different lengths and magnitudes to the electrodes on the catheter 105. The electric pulses can be delivered in a continuous pulse stream or multiple discrete pulse trains. Pulse parameters of interest include the number of pulses, pulse duty cycle, pulse train spacing, pulse voltage or magnitude (including peak voltage), and voltage duration. For example, the console 130 can select two or more electrodes of an electrode assembly and deliver pulses to the selected electrodes to generate an electric field between the selected electrodes and provide pulsed field ablation (PFA). For example, PFA can be performed using monophasic and biphasic waveforms. Without being limited to a particular theory, electric field strengths in the range of approximately 200-250 volts per centimeter (V / cm) with microsecond-scale pulse durations have been demonstrated to provide reversible electroporation in cardiac tissue. Electric field strengths of approximately 400 V / cm have been demonstrated to provide irreversible electroporation in cardiac tissues of interest (e.g., targeted myocardial and endocardial tissues) with demonstrable sparing of red blood cells, vascular smooth muscle tissue, endothelial tissue, nerves, and other non-target nearby tissues.

[0040] Another problem encountered during cardiac ablation is the inadvertent migration of catheter electrodes back into the elongate sheath during manipulation, without the clinician realizing it. For example, bipolar catheters may include a shaft electrode proximal to an electrode deployment mechanism, such as a basket, which, if misplaced within the sheath during ablation, can be inefficient or ineffective, potentially resulting in a prolonged procedure or unsuccessful treatment.

[0041] 2 illustrates a catheter assembly locking mechanism 200 that may be used with the exemplary electrophysiology system 50 and that may correspond to the locking mechanism 120 of the exemplary electroporation catheter system 60 that may be used with the introducer sheath 110. In this example, the locking mechanism 200 is configured to be operably coupled to an elongate sheath 202 and configured to coaxially receive an elongate catheter 204 within the elongate sheath 202 to form a catheter assembly 206. The locking mechanism 200 includes a deformable tube 210 and a plurality of opposing paddles 230a, 230b. The deformable tube 210 includes an outer wall 212 and an inner wall 214. The inner wall 214 defines an axial lumen 216 along an axis A. For illustrative purposes, the outer wall 212 has an outer diameter D. out It includes the secant line segment passing through axis A, defined as

[0042] In the illustrated example, the deformable tube 210 includes an open proximal end 220 and an open distal end 222. The distal end 222 is configured to be operably coupled to an elongate sheath 202 having a sheath lumen along an axis A. The proximal end 220 is configured to receive a catheter 204 within the lumen 216 and within the sheath lumen of the sheath 202 along an axis A to form a catheter assembly 206.

[0043] A plurality of at least partially overlapping opposing paddles 230a, 230b, including two paddles in the illustrated example, are positioned against the outer wall 212 of the deformable tube 210. Each of the paddles 230a, 230b has an outer diameter D out The generally planar locking regions 232a, 232b are configured to contact the outer wall 212 generally perpendicular to a secant of the outer diameter D, such that the generally planar locking regions 232a, 232b are tangential to the outer wall 212 when contacting the outer wall 212 at a point in their normal, or undeformed, state. For example, the planes of the locking regions 232a, 232b are tangent to the outer wall 212 when contacting the outer wall 212 at a point in their normal, or undeformed, state. outIn the illustrated example, the generally planar locking regions 232a, 232b are generally parallel to one another. The paddles 230a, 230b are movable relative to one another. In one example, at least one of the paddles 230a, 230b is movable relative to the deformable tube 210. In one example, the paddles 230a, 230b are movable relative to the deformable tube 210 along a line of movement that is generally perpendicular to the axis A. In another ... out The paddles 230a, 230b are movable relative to the deformable tube 210 to move generally parallel to one another perpendicularly along a secant of the paddle. As shown, the generally planar locking regions 232a, 232b of the opposing paddles 230a, 230b overlap the deformable tube 210 when they contact the outer wall 212 at the overlap region 234. The locking regions 232a, 232b include a height H and a width W. In one example, the height of each locking region 232a, 232b is the same, and the width of each locking region 232a, 232b is the same.

[0044] The drive mechanism 236 can be used to move and selectively position the paddles 230a, 230b relative to the deformable tube 210. Several suitable drive mechanisms 234 are envisioned, including manually positioning the paddles 230a, 230b relative to the deformable tube 210. For example, the drive mechanism 236 can effect selective movement of the paddles 230a, 230b along a line of movement perpendicular to the axis or outer diameter D out In one example, the position of the paddles 230a, 230b relative to the deformable tube 210 or the outer diameter D of the locking regions 232a, 232b may be adjusted by adjusting the position of the paddles 230a, 230b relative to the deformable tube 210 or the outer diameter D of the locking regions 232a, 232b. outThe position of the paddles 230 a, 230 b along the secant line may be held in place by a suitable stop mechanism used in conjunction with the drive mechanism 236. The drive mechanism 234 may be configured to move both paddles 230 a, 230 b simultaneously toward axis A relative to the deformable tube 210, or to move both paddles 230 a, 230 b simultaneously away from axis A relative to the deformable tube 210. In another example, the drive mechanism 236 may be configured to move one paddle toward axis A relative to the deformable tube 210 and the other paddle, or to move one paddle away from axis A relative to the deformable tube 210 and the other paddle.

[0045] 3A-3C illustrate various exemplary states of a cross section 300 of an exemplary catheter assembly locking mechanism 200, taken along line 3-3 of FIG. 2, or in a cross-sectional plane perpendicular to axis A. As shown, paddles 230a, 230b are selectively positionable relative to deformable tube 210 to set the locking mechanism in one of a plurality of states based on compression of the deformable tube caused by paddles 230a, 230b, which deforms lumen 216. For purposes of illustration, a cross section 300 passing through axis A and having an outer diameter D out There is a bisector B perpendicular to the axis A and the outer diameter D. out is located in a diameter plane, and axis A and bisector line B are located in a bisector plane perpendicular to the diameter plane. in The catheter 204 received within the locking mechanism 200 has an outer diameter of the catheter with a length of the inner diameter D in is chosen to be shorter than the length of

[0046] 3A, in a first or reference state 320, the paddles 230a, 230b are not in contact with or are lightly in contact with the outer wall 212 of the deformable tube 210. The catheter 204 is received within the locking mechanism 200. The outer diameter of the catheter 204 is the length of the inner diameter D in, and the catheter 204 can move freely along axis A relative to the sheath 202. In the reference state 320, the paddles 230a, 230b do not compress the inner wall 214, deform the lumen 216, or compress the inner wall 214 or deform the lumen 216 sufficiently to pinch or apply force to the catheter 204, thereby allowing the catheter 204 to move along axis A relative to the locking mechanism 200 and sheath 202. Furthermore, in the reference state 320, a fluid, such as saline, can flow between the inner wall 214 and the catheter 204 and down the catheter assembly 206, such as within the lumen of the sheath 202 between the catheter 204 and the sheath 202.

[0047] 3B, in a second state, first compressed or sheath locked state 330, catheter 204 is received within locking mechanism 200. Paddles 230a, 230b releasably press against deformable tube 210 at outer wall 212, deforming inner wall 214 and thereby pinching catheter 204 at overlap region 234 or compressing outer diameter D against catheter 204. out A force along the line is applied to hold the catheter 204 in place relative to the deformable tube 210 and sheath 202. In the sheath locked state 330, the paddles 230a, 230b compress the inner wall 214, deforming the lumen 216. In one example, the shape of the lumen 216 formed by the inner wall 214 in a cross-sectional plane perpendicular to the axis A of the overlap region 234 is no longer circular, but elliptical. The outer diameter D of the cross-sectional shape of the lumen 216 formed by the inner wall 214 is outThe distance along line B is the same as the length of diameter C of catheter 204. The distance along bisector B of the cross-sectional shape of lumen 216 formed by inner wall 214 is longer than the length of diameter C of catheter 204. In one example, the distance along bisector B of the cross-sectional shape of lumen 216 formed by inner wall 214 is longer than the length of the diameter of lumen 216 in the reference state. The collapsed deformable tube 210, which sandwiches catheter 204 along the bisector plane at overlap region 234, includes an opening 240 that is between catheter 204 and inner wall 214 along the bisector plane, as shown along bisector B.

[0048] In the sheath locked state 330, the catheter 204 sandwiched within the locking mechanism 200 is not movable relative to the sheath 202, but fluids such as saline can still flow down the catheter assembly 206 through the locking mechanism 200.

[0049] 3C , in a third state, a second compressed state, or airlock state 340, the catheter 204 is removed from the locking mechanism 200. The paddles 230 a, 230 b releasably press against the deformable tube 210 at the outer wall 212, deforming the inner wall 214 to collapse the deformable tube 210 and seal the lumen 216. The inner wall 214 is pressed against each other at the overlap region 234 along the diametric and bisector planes, as shown along the bisector B. In the airlock state 340, fluids, such as saline or air, do not enter the sheath 202 from the proximal end 220. In the illustrated example, the height H of the locking region is greater than the diametric length of the outer wall 212. For example, the height H is greater than half the circumferential length of the inner wall 214. For example, at least one-quarter of the circumferential length of the inner wall 214 is on each side of the diametric plane. In this configuration, locking regions 232a, 232b can apply a force across inner wall 214 along overlap region 234 against deformable tube 210 in airlocked state 340. Additionally, width W is a dimension effective to maintain a seal under applied pressure within locking mechanism 200.

[0050] 4 and 5 illustrate a catheter locking mechanism 400 that can be used with the exemplary electrophysiology system 50 and that may correspond to the exemplary locking mechanism 120 and the exemplary locking mechanism 200 of the exemplary electroporation catheter system 60. In this example, the locking mechanism 400 is configured to be operably coupled to an elongate sheath 402 and configured to coaxially receive an elongate catheter 404 within the elongate sheath 402 to form a catheter assembly 406. The locking mechanism 400 includes a deformable tube 410 and a plurality of opposing paddles 430 a, 430 b. The deformable tube 410 includes an outer wall 412. The deformable tube 410 includes a proximal end 420 and a distal end 422. The locking mechanism 400 includes a proximal hub 424 coupled to the proximal end 420 of the deformable tube 410 to receive the catheter 404. The locking mechanism 400 also includes a distal hub 426 coupled to the distal end 422 of the deformable tubing 410, which is coupled to the sheath 402. In one example, the proximal hub 424 is a valve hub that can be coupled to tubing to introduce fluids, such as saline, into the locking mechanism 400. The valve hub can also form a dynamic seal on the catheter 404, reducing the possibility of air ingress or fluid leakage during use, even when the catheter is moved or translated. The proximal hub 424 can be shaped and configured to receive and guide the catheter 404 along the axis AA of the locking mechanism 400 and catheter assembly 406. The distal hub 426 is configured to be operably coupled to the elongate sheath 402 to hold the sheath 402 in place relative to the locking mechanism 400.

[0051] A plurality of at least partially overlapping opposing paddles 430a, 430b, including two paddles in the illustrated example, are positioned relative to the outer wall 412 of the deformable tube 410. Each of the paddles 430a, 430b includes a substantially planar locking region 432a, 432b that is substantially parallel to one another. The locking regions 432a, 432b are configured to contact the outer wall 412 generally at an overlap region 434. The substantially planar locking regions 432a, 432b are tangential to the outer wall 412 when contacting the outer wall 412 at a point in their normal, or undeformed, state. The plurality of paddles 430a, 430b are movable relative to one another and with the deformable tube 410 via a drive mechanism (not shown) or the like. In one example, the paddles 430a, 430b are coupled to shafts 436a, 436b, which may be coupled to the drive mechanism.

[0052] The flexible tube 410 is selected from a soft, resilient material so that it can flex through numerous locking and unlocking cycles without tearing or permanently deforming. In addition, the wall thickness of the flexible tube is selected so that it compresses under the compressive force of the paddles 430a, 430b. Furthermore, the length of the flexible tube is selected so that the deformed portions under the compressive force of the paddles do not place undue stress on the connections between the ends 420, 422 and the hubs 424, 426. For example, the ends 420 and 422 are spaced apart from the overlap region 434.

[0053] 4A and 5A show the locking mechanism 400 in a first, or reference, state 520. The paddles 430a, 430b are not in contact with the outer wall 412 of the deformable tube 410, or the locking regions 432a, 432b are in light contact with the outer wall 412, and the locking regions 432a, 432b are spaced apart by a first distance. The catheter 404 is received within the locking mechanism 400, and the catheter 404 is free to move along the axis AA relative to the locking mechanism 400 and the sheath 402. In the reference state, a fluid, such as saline, can flow into the locking mechanism 400 and down the catheter assembly 206, such as within the lumen of the sheath 202 between the catheter 204 and the sheath 202 in the reference state 520.

[0054] 4B and 5B show the locking mechanism 400 in a second state, i.e., a sheath-locked state 530. The catheter 404 is received within the locking mechanism 400 in the sheath-locked state 530. The paddles 430a, 430b are releasably pressed, such as with a drive mechanism, against the deformable tube 410 at the overlap region 434 to deform or flatten the tube 410. The locking regions 432a, 432b are spaced apart a second distance that is less than the first distance. The deformable tube is collapsed against the catheter 404, and the compressive force of the paddles 430a, 430b in a direction toward the axis AA is at least sufficient to hold the catheter 404 in place relative to the deformable tube 410 and sheath 402. By selecting the sheath lock state 530 before performing ablation, such as electroporation, the clinician can reduce the possibility of the catheter 404 moving through the shaft 402, and in particular the possibility of the electrodes on the catheter shaft moving into the sheath 402.

[0055] 4C and 5C show the locking mechanism 400 in a third state, i.e., airlock state 540. The catheter 404 has been removed from the locking mechanism 400 and is not present within the locking mechanism 400 in the sheath-locked state 540. The paddles 430a, 430b are releasably pressed, such as by a drive mechanism, against the deformable tube 410 at the overlap region 434 to deform or flatten the tube 410. The locking regions 432a, 432b are spaced apart by a third distance that is less than the second distance. The deformable tube is collapsed, and the axial force of the paddles 430a, 430b is at least sufficient to seal the inner lumen within the deformable tube. A clinician can reduce the possibility of air ingress into the sheath 402 by selecting the airlock state 540 prior to, for example, inserting a device into the sheath 402. Paddles 430a, 430b may be configured to apply a constant positive pressure to deformable tube 410 via a drive mechanism while in sheath lock state 430 and air lock state 440.

[0056] 6A-6C show cross sections 600 (e.g., top cross sections) of the locking mechanism 400 along line 6-6 of FIGS. 5A-5C in various states of the locking mechanism 400. For example, the cross sections may be taken along the diametric plane of FIGS. 3A-3C. FIGS. 6A-6C show that the proximal hub 424 is configured to guide the catheter 404 into the inner lumen 416 of the deformable tube 410, formed by the inner wall 414 of the deformable tube 410. The distal hub 426 is configured to attach to the sheath 402 and hold the sheath 404 in place relative to the locking mechanism 400. When viewing the locking mechanism 400 in the diametric plane, the inner wall 414 has an inner diameter D in and the outer wall 412 has an outer diameter D out It includes the secant line segment passing through axis A, which is defined as

[0057] In FIG. 6A (obtained along line 6A-6A of FIG. 5A), when the substantially planar lock regions 432a, 432b contact the outer wall 412 at a point in their reference or undeformed state, they are tangential to the outer wall 212. Also, the planes of the lock regions 432a, 432b are perpendicular to the secant line of the outer diameter D in FIGS. 6A - 6C. In the illustrated example, the substantially planar lock regions 432a, 432b are substantially parallel to each other. The plurality of paddles 430a, 430b are movable relative to each other. In one example, the paddles 430a, 430b are movable relative to the deformable tube 410 along a movement line substantially perpendicular to the axis AA. In another example, the paddles 430a, 430b are movable relative to the deformable tube 410 such that the planes of the lock regions 432a, 432b move substantially parallel to each other perpendicularly along the secant line of the outer diameter D. In the figure, the substantially planar lock regions 432a, 432b of the opposing paddles 430a, 430b overlap the deformable tube 410 when contacting the outer wall 412 in the overlap region 434. The lock regions 432a, 432b provide a width W that includes a sufficiently long overlap region 434 on the axis AA to maintain the catheter hold in the sheath lock state 530 of FIG. 6C and to maintain the seal of the inner wall 414 under positive pressure within the lock mechanism 400 in the air lock state 540 of FIG. 6C. In one example, the paddles 430a, 440b are arranged such that the width of each lock region 432a, 432b is located within the overlap region 434. out In the illustrated example, the substantially planar lock regions 432a, 432b are substantially parallel to each other. The plurality of paddles 430a, 430b are movable relative to each other. In one example, the paddles 430a, 430b are movable relative to the deformable tube 410 along a movement line substantially perpendicular to the axis AA. In another example, the paddles 430a, 430b are movable relative to the deformable tube 410 such that the planes of the lock regions 432a, 432b move substantially parallel to each other perpendicularly along the secant line of the outer diameter D. In the figure, the substantially planar lock regions 432a, 432b of the opposing paddles 430a, 430b overlap the deformable tube 410 when contacting the outer wall 412 in the overlap region 434. The lock regions 432a, 432b provide a width W that includes a sufficiently long overlap region 434 on the axis AA to maintain the catheter hold in the sheath lock state 530 of FIG. 6C and to maintain the seal of the inner wall 414 under positive pressure within the lock mechanism 400 in the air lock state 540 of FIG. 6C. In one example, the paddles 430a, 440b are arranged such that the width of each lock region 432a, 432b is located within the overlap region 434. out In the illustrated example, the substantially planar lock regions 432a, 432b are substantially parallel to each other. The plurality of paddles 430a, 430b are movable relative to each other. In one example, the paddles 430a, 430b are movable relative to the deformable tube 410 along a movement line substantially perpendicular to the axis AA. In another example, the paddles 430a, 430b are movable relative to the deformable tube 410 such that the planes of the lock regions 432a, 432b move substantially parallel to each other perpendicularly along the secant line of the outer diameter D. In the figure, the substantially planar lock regions 432a, 432b of the opposing paddles 430a, 430b overlap the deformable tube 410 when contacting the outer wall 412 in the overlap region 434. The lock regions 432a, 432b provide a width W that includes a sufficiently long overlap region 434 on the axis AA to maintain the catheter hold in the sheath lock state 530 of FIG. 6C and to maintain the seal of the inner wall 414 under positive pressure within the lock mechanism 400 in the air lock state 540 of FIG. 6C. In one example, the paddles 430a, 440b are arranged such that the width of each lock region 432a, 432b is located within the overlap region 434.

[0058] As shown in FIG. 6A, in the first state, i.e., the reference state 520, the paddles 430a, 430b lightly contact the outer wall 412. The outer diameter length of the catheter 404 is shorter than the length of the inner diameter D in and the catheter 404 can move freely along the axis A relative to the inner wall 414 and the sheath 402.

[0059] As shown in FIG. 6B (taken along line 6B-6B of FIG. 5B), in a second state, or sheath-locked state 530, the catheter 404 is received within the locking mechanism 400. The paddles 430a, 430b releasably press against the deformable tube 410 at the outer wall 412, causing the inner wall 414 to deform, thereby pinching the catheter 404 at the overlap region 434, or sheathing the catheter 404 to an outer diameter D out A force along this line is applied to hold the catheter 404 in place relative to the deformable tube 410 and sheath 402. In the sheath locked state 530, the paddles 430a, 430b compress the inner wall 414, causing the lumen 416 to deform.

[0060] 6C (taken along line 6C-6C of FIG. 5C ), in a third state, or airlock state 540, the catheter 504 is removed from the locking mechanism 500. The paddles are releasably pressed against the deformable tube 510 at the outer wall 512, deforming the inner wall 514 to collapse the deformable tube 510 and seal the lumen 516 in the diametric plane. The inner walls 414 are pressed together at the overlap region 434, and fluids, such as saline or air, cannot enter the locking mechanism 400 into the sheath 402.

[0061] 7A-7C show cross sections 700 (e.g., side cross-sectional views) of locking mechanism 400 taken along line 7-7 of FIGS. 4A-4C in various states of locking mechanism 400. For example, the cross sections may be taken along the bisector plane of FIGS. 3A-3C. When viewing locking mechanism 400 at the bisector plane, outer wall 412 includes a secant segment through axis AA, defined as bisector B.

[0062] As shown in FIG. 7A (taken along line 7A-7A in FIG. 4A), in a first or reference state 520, catheter 404 is received within locking mechanism 400. Paddles 430a, 430b do not contact deformable tube 404 sufficiently to deform inner wall 414 to prevent catheter 404 from moving freely along axis AA. In particular, inner wall 414 is not deformed along bisector B to prevent catheter 404 from moving freely along axis AA.

[0063] As shown in FIG. 7B (taken along line 7B-7B of FIG. 4B), in a second state, i.e., sheath-locked state 530, paddles 430a, 430b are releasably pressed against deformable tube 410 at outer wall 412, causing inner wall 414 to deform, thereby pinching catheter 404 at overlap region 434 or forcing outer diameter D against catheter 404. outA force is applied along line B to hold the catheter 404 in place relative to the deformable tube 410 and sheath 402. The paddles 430a, 430b compress the inner wall 414, deforming the lumen 416. In one example, the shape of the lumen 416 formed by the inner wall 414 at the overlap region 434 is no longer circular but elliptical. The distance along bisector B of the cross-sectional shape of the lumen 416 formed by the inner wall 414 is longer than the length of the diameter C of the catheter 404. In one example, the distance along bisector B of the cross-sectional shape of the lumen 416 formed by the inner wall 414 is longer than the length of the diameter C of the lumen 416 in the reference state. The collapsed deformable tube 410, which sandwiches the catheter 404 along the bisector plane at the overlap region 434, includes an opening 440 between the catheter 404 and the inner wall 414 along the bisector plane, as shown along bisector B. In the sheath locked state 530, the catheter 404, which is sandwiched within the locking mechanism 400, is not movable relative to the sheath 402, but fluids such as saline can still flow down the catheter assembly 406 through the locking mechanism 400. As shown in Figure 7B, saline can still flow down the catheter assembly 406 through the opening 440 even though the catheter 404 is sandwiched against the inner wall 414 along the diametric plane as shown in Figure 6B.

[0064] As shown in FIG. 7C (taken along line 7C-7C of FIG. 4C ), in a third state, or airlock state 540, the catheter 404 is removed from the locking mechanism 400. The paddles 430 a, 430 b releasably press against the deformable tube 410 at the outer wall 412, deforming the inner wall 414 to collapse the deformable tube 410 and seal the lumen 416. The inner walls 414 are pressed against each other at the overlap region 434 along the diametric and bisector planes, as shown along the bisector B. In the airlock state 540, fluids, such as saline or air, do not enter the sheath 402 from the proximal end 420. In the illustrated example, the height H of the locking region is greater than the length of the diameter of the outer wall 412. In this configuration, locking regions 432a, 432b can apply a force across inner wall 414 along overlap region 434 against deformable tube 410 in airlocked state 440. Additionally, width W is a dimension effective to maintain a seal under applied pressure within locking mechanism 400.

[0065] Various modifications and additions may be made to the exemplary embodiments described without departing from the scope of the present disclosure. For example, while the embodiments described above refer to particular features, the scope of the present disclosure also includes embodiments having different combinations of features and embodiments that do not include all of the described features. Accordingly, the scope of the present disclosure is intended to encompass all such alternatives, modifications, and variations that fall within the scope of the claims, together with all equivalents thereof.

Claims

1. 1. A medical device for use in a catheter assembly including an elongate catheter coaxially disposed within a sheath, comprising: a deformable tube having a proximal end, a distal end, an outer wall having an outer diameter, and an inner wall forming an axial lumen, the distal end configured to be attached to the sheath and the proximal end configured to receive the catheter within the lumen; a plurality of opposing paddles disposed against the outer wall, each of the plurality of opposing paddles having a generally planar locking region configured to be disposed against the outer wall at the outer diameter, a locking surface disposed tangentially to the deformable tube, the plurality of opposing paddles being movable laterally relative to the deformable tube at a position along the outer diameter; the medical device has a first compressed state in which the catheter is coaxially disposed within the sheath and the plurality of opposing paddles are releasably pressed against the deformable tube at the outer diameter to collapse the deformable tube and hold the catheter in place relative to the sheath and the deformable tube, the collapsed deformable tube forming an elongated opening along the inner wall and the catheter; the medical device has a second compressed state in which the catheter is not coaxially disposed within the sheath and is removed from the deformable tube, and the plurality of opposing paddles are releasably pressed against the deformable tube at the outer diameter to collapse the deformable tube and seal the lumen.

2. The medical device of claim 1 , wherein the catheter assembly is integrated into the medical device.

3. The medical device of claim 1 or 2, wherein the catheter assembly is configured to perform irreversible electroporation.

4. 4. The medical device of claim 1, further comprising a reference state in which the catheter is coaxially disposed within the sheath and the catheter is movable relative to the sheath and the deformable tube.

5. The medical device of claim 4 , wherein the inner wall comprises a circular cross-section in the reference state.

6. The medical device of claim 5 , wherein the locking region includes a height, the inner wall includes a circumference, and the height is at least half of the circumference.

7. The medical device of claim 4 or 5, wherein the inner wall comprises an elliptical cross-section in the first compressed state.

8. The medical device of claim 1 , wherein the plurality of opposing paddles comprises two opposing paddles.

9. The medical device of claim 8 , wherein the locking regions are generally parallel to one another.

10. The medical device of claim 1 , wherein the locking region forms an overlap region on the deformable tube.

11. The medical device of claim 10 , wherein the inner wall associated with the overlap region sandwiches the catheter in the first compressed state.

12. The medical device of claim 10 or 11, wherein the interior wall associated with the overlap region seals the lumen in the second compressed state.

13. The medical device of claim 10 , wherein the proximal end and the distal end are spaced apart from the overlap region.

14. 14. The medical device of claim 1, wherein the proximal end includes a proximal hub configured to guide the catheter into the lumen, and the distal end includes a distal hub configured to be attached to the sheath.

15. 15. The medical device of claim 1, further comprising a drive mechanism operably coupled to the plurality of opposing paddles, the drive mechanism configured to move the plurality of opposing paddles laterally relative to the deformable tube.

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