CN118252587A

CN118252587A - Basket end effector with distal position sensor

Info

Publication number: CN118252587A
Application number: CN202310477350.6A
Authority: CN
Inventors: J·T·凯斯; K·J·埃雷拉; N·詹金斯
Original assignee: Biosense Webster Israel Ltd
Current assignee: Biosense Webster Israel Ltd
Priority date: 2022-12-28
Filing date: 2023-04-28
Publication date: 2024-06-28

Abstract

The systems and methods presented herein generally include a catheter having a basket assembly at a distal tip with an atraumatic structure on a distal portion of the basket assembly and a distal sensor coupled to the atraumatic structure. The basket assembly includes a ridge that collapses for delivery through the delivery sheath catheter and self-expands upon exiting the distal end of the delivery sheath catheter. The basket assembly may also include a proximal sensor coupled to the shaft of the catheter, and when the basket assembly is pressed to tissue or another surface, position signals from the shaft sensor and the distal sensor may be used to determine the position of the electrodes of the basket assembly.

Description

Basket end effector with distal position sensor

Cross Reference to Related Applications

The present application claims priority from U.S. c. ≡119 to U.S. provisional patent application No. 63/477,425 (attorney docket 253757.000256-BIO6743USPSP No. 1) previously filed on day 28 of 12 of 2022, the entire contents of which are hereby incorporated by reference as if fully set forth herein.

Technical Field

The present invention relates generally to medical devices, and more particularly to catheters having electrodes configured to map and/or ablate tissue, and further, but not exclusively, to catheters suitable for inducing irreversible electroporation (IRE) of cardiac tissue.

Background

Arrhythmia, such as Atrial Fibrillation (AF), may occur when areas of heart tissue abnormally conduct electrical signals to adjacent tissue. This can disrupt the normal cardiac cycle and lead to arrhythmia. Certain protocols are used to treat cardiac arrhythmias, including surgically disturbing the source of the signals responsible for the arrhythmia and disturbing the conduction pathways for such signals. By selectively ablating cardiac tissue by applying energy through the catheter, it is sometimes possible to stop or alter the propagation of unwanted electrical signals from one portion of the heart to another.

Many current ablation methods in the art tend to utilize Radio Frequency (RF) electrical energy to heat tissue. RF ablation may have some rare drawbacks due to the skill of the operator, such as an increased risk of thermal cell damage, which may lead to charring of tissue, burns, steam pops, phrenic nerve paralysis, pulmonary vein stenosis, and esophageal fistulae. Cryoablation is an alternative to RF ablation, which may reduce some of the thermal risks associated with RF ablation, but may cause tissue damage due to the very low temperature nature of such devices. However, manipulating a cryoablation device and selectively applying cryoablation is generally more challenging than RF ablation; thus, cryoablation is not feasible in certain anatomical geometries that may be reached by an electrical ablation device.

Some ablation methods use irreversible electroporation (IRE) to ablate cardiac tissue using non-thermal ablation methods. IRE delivers short pulses of high pressure to the tissue and produces unrecoverable cell membrane permeabilization. The use of multi-electrode catheters to deliver IRE energy to tissue has previously been proposed in the patent literature. Examples of systems and devices configured for IRE ablation are disclosed in U.S. patent publications 2021/0169550A1, 2021/0169567A1, 2021/0169568A1, 2021/0161592A1, 2021/0196372A1, 2021/0177503A1 and 2021/0186604A1, each of which is incorporated herein by reference in its entirety for the appendix of the priority patent application 63/477,425.

Areas of cardiac tissue may be mapped by the catheter to identify abnormal electrical signals. Ablation may be performed using the same or different catheters. Some example catheters include a plurality of ridges on which electrodes are disposed. The electrodes are typically attached to the ridges and secured in place by brazing, welding, or using an adhesive. Further, the plurality of linear ridges are typically assembled together to form a ball basket by attaching both ends of the linear ridges to a tubular shaft (e.g., a pusher tube). It is desirable to have an atraumatic basket shape so that when the basket is pressed against tissue, the tissue is not damaged and it is desirable to visualize the position of the basket relative to the tissue.

Disclosure of Invention

An exemplary end effector of a catheter may include a support frame and atraumatic structure. The support frame may include a plurality of ridges configured to self-expand away from the longitudinal axis from the proximal portion to the distal ridge portion to form a basket-like configuration. The distal spine portion may define a clover configuration disposed radially about the longitudinal axis. The clover structure may define a central cutout having a central region disposed about the longitudinal axis. The clover structure may include an inner arc defining a concave perimeter about the longitudinal axis. The atraumatic structure may cover a portion of the clover structure of the support frame such that only the inner arcs of the clover structure are visible.

The end effector may also include a sensor coupled to the atraumatic structure. The end effector may further comprise a plurality of electrodes coupled to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges.

In a basket-like configuration, the sensor may be disposed in a distal direction relative to a distal surface of the support frame.

The sensor may comprise a contact force sensor. The sensor may comprise an electrocardiogram sensor. The sensor may comprise a position sensor. The position sensor may comprise an induction coil. The position sensor may comprise a magnetic sensor.

The position sensor may comprise a single axis sensor having a sensor axis coaxial with the longitudinal axis.

The atraumatic structure may comprise a flexible circuit.

The flexible circuit may include a circular portion and an elongated portion. The rounded portion may cover the distal surface of the support frame, thereby forming an atraumatic covering on the distal surface of the support frame. The elongate portion may extend proximally along a ridge of the plurality of ridges.

The single axis sensor may include a spiral conductor embedded in a circular portion of the flex circuit.

The support frame may include a distal structure connecting the ridges and defining a central cutout having a central region disposed about the longitudinal axis. The atraumatic structure may cover at least a portion of the central incision.

The distal structure may include a sinusoidal member extending from one ridge to an adjacent ridge in a direction about the longitudinal axis and forming a clover structure.

The end effector may further comprise a plurality of sheaths over the plurality of ridges.

The plurality of sheaths extends over a majority of the clover structure such that the atraumatic structure comprises a respective distal portion of each sheath of the plurality of sheaths.

The inner arc extends from the distal ends of the plurality of sheaths and between adjacent sheaths of the plurality of sheaths.

The end effector may also include a plurality of electrodes positioned in pairs such that each ridge includes a respective pair of electrodes, and such that the pair of electrodes of a ridge does not longitudinally overlap the pair of electrodes of an adjacent ridge.

Each electrode may include a body defining a hollow portion extending through the electrode body such that the ridge may be inserted into the hollow portion and retained on the ridge. Each ridge may include a retaining member configured to be compressed to allow movement of the electrode on the retaining member. The retaining member may be configured to expand to inhibit movement of the electrode along the ridge.

The plurality of electrodes may be configured to deliver an electrical pulse for irreversible electroporation, the pulse comprising a peak voltage of at least 900 volts (V).

The plurality of ridges may be configured to form an approximately spherical basket assembly when in the basket configuration.

The plurality of ridges may be configured to form an approximately oblate spheroid basket assembly when in the basket configuration.

Another example end effector may include a support frame, an atraumatic structure, a sensor, and a plurality of electrodes. The support frame may include a plurality of ridges configured to expand away from the longitudinal axis. The atraumatic structure may be coupled to a plurality of ridges at a distal end of the support frame. The sensor may be coupled to the atraumatic structure and positioned distally of the support frame. The plurality of electrodes may be coupled to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges.

The atraumatic structure may comprise a rigid, electrically insulating structure.

The atraumatic structure may be configured to maintain a relative position of a ridge of the plurality of ridges at the distal surface of the support frame.

The position sensor may include a single axis sensor, a dual axis sensor, and/or a three axis sensor.

The sensor may comprise a contact force sensor. The sensor may comprise an electrocardiogram sensor. The sensor may comprise a position sensor. The position sensor may comprise an induction coil. The position sensor may comprise a magnetic sensor. The position sensor may comprise a single axis sensor having a sensor axis coaxial with the longitudinal axis.

Each electrode may have a body defining a hollow portion extending through the electrode body such that the ridge may be inserted into the hollow portion and retained on the ridge.

Each ridge may include a retaining member configured to be compressed to allow movement of the electrode on the retaining member. The retaining member may be configured to expand to inhibit movement of the electrode along the ridge.

An exemplary system may include a catheter, at least one magnetic field radiator, and processing circuitry. The catheter may be configured to be inserted into a body part of a living subject. The catheter may include a shaft and a basket assembly. The shaft may include a first coil-based position sensor disposed near a distal end of the shaft. The basket assembly may include a self-expanding support frame and a coil-based second position sensor coupled to a distal end of the self-expanding support frame. The basket assembly may further include a plurality of electrodes coupled to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges. The at least one magnetic field radiator may be configured to transmit an alternating magnetic field into the region in which the body part is located. The first and second position sensors may be configured to output respective first and second position signals in response to the transmitted alternating magnetic field. The processing circuitry may be configured to: receiving a first position signal and a second position signal from a first position sensor and a second position sensor; calculating position and orientation coordinates of the first and second position sensors using position calculations, wherein the position and orientation coordinates of each of the position sensors are calculated iteratively inter-dependently in response to the respective received position signals; and is constrained coaxially by the first position sensor and the second position sensor; calculating a distance between the calculated position coordinates of the first position sensor and the calculated position coordinates of the second position sensor; and estimating respective locations of the plurality of ridges in response to at least the calculated distances.

Another exemplary system may include a catheter, at least one magnetic field radiator, and processing circuitry. The catheter may be configured to be inserted into a body part of a living subject. The catheter may include a shaft and a basket assembly. The shaft may include a first coil-based position sensor disposed near a distal end of the shaft. The basket assembly may include a self-expanding support frame and a coil-based second position sensor coupled to a distal end of the self-expanding support frame. The basket assembly may further include a plurality of electrodes coupled to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges. The at least one magnetic field radiator may be configured to transmit an alternating magnetic field into the region in which the body part is located. The first and second position sensors may be configured to output respective first and second position signals in response to the transmitted alternating magnetic field. The processing circuitry is configured to: receiving a first position signal and a second position signal from a first position sensor and a second position sensor; calculating a distance and a relative orientation angle between the first position sensor and the second position sensor in response to the received position signals; and estimating respective positions of the plurality of ridges in response to at least the calculated distance and the relative orientation angle while taking into account a twist of one or more of the plurality of ridges from the symmetrical arrangement when the value of the relative orientation angle is greater than zero.

The coil-based second position sensor may be disposed in a distal direction relative to a distal surface of the self-expanding support frame.

The exemplary method may include the following steps performed in various orders and may include additional steps as will be appreciated by those skilled in the art. The method may include inserting a catheter into a body part of a living subject. The catheter may include a shaft and a basket assembly. A coil-based first position sensor may be disposed at the distal end of the shaft. The basket assembly may include a self-expanding support frame and a coil-based second position sensor coupled to a distal end of the self-expanding support frame. The basket assembly may further include a plurality of electrodes coupled to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges. The method may further include exposing the basket assembly to allow the self-expanding support frame to form a basket shape. The method may further comprise transmitting an alternating magnetic field into the region in which the body part is located. The method may further include outputting, by the first and second position sensors, respective first and second position signals in response to the transmitted alternating magnetic field. The method may further include receiving a first position signal and a second position signal from the first position sensor and the second position sensor. The method may further include calculating position and orientation coordinates of the first and second position sensors using the position calculation, wherein the position and orientation coordinates of each of the position sensors are iteratively calculated in dependence upon each other in response to the respective received position signals and constrained by the first and second position sensors being coaxial. The method may further include calculating a distance between the calculated position coordinates of the first position sensor and the calculated position coordinates of the second position sensor. The method may further include estimating respective locations of the plurality of ridges in response to at least the calculated distance.

Another exemplary method may include the following steps performed in various orders and may include additional steps as would be understood by one of skill in the art. The method may include inserting a catheter into a body part of a living subject. The catheter may include a shaft and a basket assembly. A coil-based first position sensor may be disposed at the distal end of the shaft. The basket assembly may include a self-expanding support frame and a coil-based second position sensor coupled to a distal end of the self-expanding support frame. The basket assembly may further include a plurality of electrodes coupled to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges. The method may further include exposing the basket assembly to allow the self-expanding support frame to form a basket shape. The method may comprise transmitting an alternating magnetic field into the region in which the body part is located. The method may include outputting, by the first and second position sensors, respective first and second position signals in response to the transmitted alternating magnetic field. The method may include receiving a first position signal and a second position signal from a first position sensor and a second position sensor. The method may include calculating a distance and a relative orientation angle between the first position sensor and the second position sensor in response to the received position signal. The method may include estimating respective locations of the plurality of ridges in response to at least the calculated distance and the relative orientation angle, while accounting for a distortion of one or more of the plurality of ridges from a symmetrical arrangement when the value of the relative orientation angle is greater than zero.

An exemplary method of constructing a medical probe may include the following steps performed in various orders and may include additional steps as will be appreciated by those skilled in the art. The method may include forming a support frame including a plurality of ridges. The method may include configuring the plurality of ridges to be positioned about the longitudinal axis and self-expandable away from the longitudinal axis. The method may include covering a distal surface of the support frame with an atraumatic structure. The method may include coupling the sensor to an atraumatic structure. The method may include coupling a plurality of electrodes to a plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges.

The support frame may include a distal structure connecting the ridges and defining a central cutout having a central region disposed about the longitudinal axis. The central cutout may define an opening in the distal surface of the support frame.

Forming the support frame from the plurality of ridges may include cutting the tube such that the distal structure surrounds the tube and the plurality of ridges extend longitudinally along the tube.

The method may include coupling a distal portion of the plurality of ridges with the atraumatic structure.

The sensor may be embedded in the atraumatic structure.

Another exemplary method of constructing a medical probe may include the following steps performed in various orders and may include additional steps as will be appreciated by those skilled in the art. The method may include inserting a plurality of ridges into the plurality of sheaths such that the plurality of ridges extend along the longitudinal axis from a proximal central proximal ridge portion to a distal ridge portion. The distal spine portion may define a clover configuration disposed radially about the longitudinal axis. The clover structure may define a central cutout having a central region disposed about the longitudinal axis. The plurality of sheaths may each cover a majority of the distal spine portion. The method may further include aligning a plurality of ridges with a plurality of electrodes, each electrode having a lumen extending through the electrode body. The method may further include inserting each ridge of the plurality of ridges into the lumen of an electrode of the plurality of electrodes. The method may further include retaining the plurality of electrodes on the plurality of ridges.

Maintaining the plurality of electrodes on the plurality of ridges may include maintaining an electrode of the plurality of electrodes with at least one biasing member.

The at least one biasing member may be disposed outside of the lumen of the electrode.

The at least one biasing member may be disposed within the interior cavity of the electrode.

The method may further include positioning the wire through a lumen of an electrically insulating sheath of the plurality of electrically insulating sheaths. The method may also include positioning an electrode of the plurality of electrodes on the electrically insulating sheath. The method may further include electrically connecting the lead to the electrode through an aperture in the electrically insulating sheath.

Each respective ridge of the plurality of ridges may include a first electrode and a second electrode. The method may further include aligning each respective ridge of the plurality of ridges with the first electrode and the second electrode. The method may further include inserting each respective ridge of the plurality of ridges into the lumen of the first electrode and the lumen of the second electrode. The method may further include fitting an end of each respective ridge of the plurality of ridges to a tubular shaft sized to traverse the vasculature.

The method may further include offsetting the electrode along the longitudinal axis between adjacent ridges.

The electrode body lumen may be configured to receive a guidewire of a medical probe.

The wire may be insulated from the ridge.

Drawings

The above-described and further aspects of the present invention will be further discussed with reference to the following description, taken in conjunction with the accompanying drawings, in which like numerals indicate like structural elements and features in the various figures. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. The drawings depict one or more implementations of the present apparatus by way of example only and not by way of limitation.

Fig. 1 is a diagram of an exemplary catheter-based electrophysiology mapping and ablation system according to aspects of the present invention.

Fig. 2A is a perspective view of a medical probe in an expanded form according to aspects of the present invention.

Fig. 2B is an illustration of a tubular frame of a medical probe formed from a tube blank in accordance with aspects of the invention.

Fig. 2C is an illustration of a distal end view of the basket assembly of fig. 2A in accordance with aspects of the present invention.

Fig. 3A is another illustration of a distal end view of the basket assembly of fig. 2A with an atraumatic distal cover omitted from illustration, in accordance with an aspect of the present invention.

Fig. 3B is another illustration of a distal end view of the basket assembly of fig. 2A with the atraumatic distal cover omitted from illustration, in accordance with an aspect of the present invention.

Fig. 3C is another illustration of a distal end view of the basket assembly of fig. 2A with the atraumatic distal covering omitted from illustration, in accordance with an aspect of the present invention.

Fig. 4A is a perspective view of the basket-like distal end shown in fig. 2A to illustrate the concavity of the distal end.

Fig. 4B is a side view of the basket-like distal end shown in fig. 2A to illustrate the concavity of the distal end.

Fig. 5A is a perspective view of another exemplary medical probe in an expanded form according to aspects of the present invention.

Fig. 5B is a distal end view of the medical probe shown in fig. 5A.

Fig. 5C is an exploded view of the medical probe shown in fig. 5A.

Fig. 6A is an illustration of an end flat view of the distal end of the basket ridge structure of fig. 5A as if the entire basket ridge were captured flat between two flat glass plates for viewing by a viewer on the longitudinal axis.

Fig. 6B is an illustration of a distal sensor of a basket distal end in accordance with aspects of the present invention.

Fig. 7A is an illustration of a perspective view of another exemplary medical probe according to aspects of the present invention.

Fig. 7B is an illustration of a perspective view of the distal end of the medical probe shown in fig. 7A.

Fig. 7C is an illustration of a ring-friendly hub of a medical probe according to aspects of the invention.

FIG. 8A is a flow chart including steps in a method of operation of the system of FIG. 1 using an exemplary basket catheter in accordance with aspects of the present invention.

Fig. 8B is a flow chart including sub-steps in the method of operation of fig. 8A.

Fig. 8C is a flow chart including alternative sub-steps in the method of operation of fig. 8A.

FIG. 9 is a flow chart of steps in another method of operation of the system including FIG. 1 using an exemplary basket catheter in accordance with aspects of the present invention.

Detailed Description

The detailed description illustrates by way of example, and not by way of limitation, the principles of the invention. This description will clearly enable one skilled in the art to make and use the invention, and describes several embodiments, adaptations, variations, alternatives and uses of the invention, including what is presently believed to be the best mode of carrying out the invention.

As used herein, the term "about" or "approximately" for any numerical value or range indicates a suitable dimensional tolerance that allows a collection of parts or components to achieve the intended purpose thereof as described herein. More specifically, "about" or "approximately" may refer to a range of values of ±20% of the recited values, for example "about 90%" may refer to a range of values of 71% to 110%.

As used herein, the terms "patient," "subject," "user," and "subject" refer to any human or animal subject, and are not intended to limit the system or method to human use, but use of the subject invention in a human patient represents a preferred embodiment. Furthermore, the vasculature of a "patient," "subject," "user," and "subject" may be that of a human or any animal. It should be understood that the animal may be of any suitable type including, but not limited to, a mammal, a veterinary animal, a livestock animal or a companion animal, and the like. For example, the animal may be a laboratory animal (e.g., rat, dog, pig, monkey, etc.) specifically selected to have certain characteristics similar to humans. It should be appreciated that the subject may be, for example, any suitable human patient.

As used herein, the term "proximal" refers to a location closer to an operator or physician, and "distal" refers to a location further from an operator or physician.

As used herein, an "operator" may include a doctor, surgeon, technician, scientist, or any other individual or delivery meter device associated with delivering a multi-electrode catheter for treating drug refractory atrial fibrillation to a subject.

As used herein, the term "ablation" when referring to the devices and corresponding systems of the present disclosure refers to components and structural features configured to reduce or prevent the generation of unstable cardiac signals in cells by utilizing non-thermal energy, such as irreversible electroporation (IRE), interchangeably referred to in the present disclosure as Pulsed Electric Field (PEF) and Pulsed Field Ablation (PFA). "ablation" as used throughout the present disclosure, when referring to the devices and corresponding systems of the present disclosure, refers to non-thermal ablation of cardiac tissue for certain conditions, including, but not limited to, arrhythmia, atrial flutter ablation, pulmonary vein isolation, supraventricular tachycardia ablation, and ventricular tachycardia ablation. The term "ablation" also includes known methods, devices and systems for effecting various forms of body tissue ablation, including thermal ablation, as understood by those skilled in the relevant art.

As discussed herein, the terms "bipolar" and "monopolar (bipolar and unipolar/monopolar)" when used to refer to an ablation protocol describe an ablation protocol that differs in terms of current path and electric field distribution. "bipolar" refers to an ablation protocol that utilizes a current path between two electrodes, both of which are positioned at a treatment site; the current density and the current flux density at each of the two electrodes are typically approximately equal. "monopolar" (unipolar and monopolar) are used interchangeably herein to refer to an ablation procedure utilizing a current path between two electrodes, wherein one electrode comprising a high current density and a high electrical flux density is positioned at the treatment site and a second electrode comprising a relatively lower current density and a lower electrical flux density is positioned away from the treatment site.

As discussed herein, the terms "tubular" and "tube" are to be understood in a broad sense and are not limited to structures that are right circular cylinders or that are entirely circumferential in cross-section or have a uniform cross-section throughout their length. For example, the tubular structure is generally shown as a substantially right circular cylinder structure. However, the tubular structure may have a tapered or curved outer surface without departing from the scope of the present disclosure.

Any one or more of the teachings, expressions, patterns, examples, etc. described herein can be combined with any one or more of the other teachings, expressions, patterns, examples, etc. described herein. Thus, the following teachings, expressions, versions, examples, etc. should not be considered as being separate from each other. Various suitable ways in which the teachings herein may be combined will be apparent to those skilled in the relevant art(s) in view of the teachings herein. Such modifications and variations are intended to be included within the scope of the appended claims.

Fig. 1 is a diagram illustrating an exemplary catheter-based electrophysiology mapping and ablation system 10. The system 10 includes a plurality of catheters that are percutaneously inserted by a physician 24 through the vascular system of a patient into a chamber or vascular structure of the heart 12. Typically, the delivery sheath catheter is inserted into the left atrium or the right atrium near the desired location in the heart 12. A plurality of catheters may then be inserted into the delivery sheath catheter in order to reach the desired location. The plurality of catheters may include catheters dedicated to sensing Intracardiac Electrogram (IEGM) signals, catheters dedicated to ablation, and/or catheters dedicated to both sensing and ablation. An exemplary catheter 14 configured for sensing IEGM and ablation is shown herein. The physician 24 brings the distal tip 28 of the catheter 14 into contact with the heart wall for sensing a target site in the heart 12.

The catheter 14 shown is an exemplary catheter that includes one and preferably a plurality of electrodes 40 optionally distributed over a plurality of ridges 214 of the basket assembly 100 at the distal tip 28 of the catheter 14 and extending distally from the distal end 85 of the catheter shaft 84. The basket assembly 100 may be configured to sense IEGM signals and/or provide ablation signals. The catheter 14 may be delivered to the heart 12 through a sheath or intermediate catheter (not shown). Catheter 14 may additionally include a position sensor 29 embedded in or near distal tip 28 for tracking the position and orientation of distal tip 28. Optionally and preferably, the position sensor 29 is a magnetic-based position sensor comprising three magnetic coils for sensing three-dimensional (3D) position and orientation. The position sensor 29 is shown on the distal portion of the catheter shaft 84 in the proximal direction of the basket assembly 100. Additionally or alternatively, basket assembly 100 may include similarly configured position sensors at the distal end of basket assembly 100. The illustrated basket assembly 100 includes atraumatic structure 45 on a distal portion of the spine 214. A position sensor or other type of sensor (such as a contact force sensor or an electrocardiogram sensor) may be coupled to atraumatic structure 45. Atraumatic structure 45 may allow the distal end of basket assembly 100 to be pressed to tissue without damaging the tissue.

One or more magnetic-based position sensors (e.g., position sensor 29 coupled to shaft 84 and/or a position sensor coupled to the distal end of basket assembly 100) may operate with a positioning pad 25 that includes a plurality of magnetic coils 32 configured to generate a magnetic field in a predetermined working volume. The real-time position of the distal tip 28 of the catheter 14 may be tracked based on the magnetic field generated with the location pad 25 and sensed by one or more magnetic-based position sensors. Details of magnetic-based position sensing techniques are described in U.S. Pat. nos. 5,391,199, 5,443,489, 5,558,091, 6,172,499, 6,239,724, 6,332,089, 6,484,118, 6,618,612, 6,690,963, 6,788,967, and 6,892,091, which are incorporated herein by reference in their appendices to the priority patent application 63/477,425.

The system 10 includes one or more electrode patches 38 positioned for skin contact on the patient 23 to establish a positioning reference for the positioning pad 25 and impedance-based tracking of the electrodes 40 and/or impedance-based sensors at the distal end of the basket assembly 100. For impedance-based tracking, current is directed toward the electrodes 40 (and/or sensors at the distal end of the basket assembly 100) and sensed at the electrode skin patches 38 so that the position of each electrode and/or sensor can be triangulated via the electrode patches 38. Details of impedance-based location tracking techniques are described in U.S. patent nos. 7,536,218, 7,756,576, 7,848,787, 7,869,865, and 8,456,182, which are incorporated herein by reference and are attached to the appendices of priority patent application No. 63/477,425.

Recorder 11 displays an electrogram 21 captured with body surface ECG electrode 18 and an Intracardiac Electrogram (IEGM) captured with electrode 40 of catheter 14 and/or a sensor at the distal end of basket assembly 100. Recorder 11 may include pacing capabilities for pacing the heart rhythm and/or may be electrically connected to a separate pacemaker.

The system 10 may include an ablation energy generator 50 adapted to conduct ablation energy to one or more of the electrodes 40 of the basket assembly 100 configured for ablation. The energy generated by ablation energy generator 50 may include, but is not limited to, radio Frequency (RF) energy or Pulsed Field Ablation (PFA) energy, including monopolar or bipolar high voltage DC pulses that may be used to achieve irreversible electroporation (IRE), or a combination thereof.

The Patient Interface Unit (PIU) 30 is an interface configured to establish electrical communication between a catheter, electrophysiological equipment, a power source, and a workstation 55 for controlling operation of the system 10. The electrophysiological equipment of system 10 can include, for example, a plurality of catheters, location pads 25, body surface ECG electrodes 18, electrode patches 38, an ablation energy generator 50, and a recorder 11. Optionally and preferably, the PIU30 includes processing capabilities for enabling real-time calculation of the position of the catheter and for performing ECG calculations.

The workstation 55 includes memory, a processor unit with memory or storage loaded with appropriate operating software, and user interface capabilities. Workstation 55 may be configured to provide a variety of functions, optionally including: (1) Three-dimensional (3D) modeling of endocardial anatomy and rendering of the model or anatomical map 20 for display on display device 27; (2) Displaying the activation sequence (or other data) compiled from the recorded electrogram 21 on the display device 27 with a representative visual marker or image superimposed on the rendered anatomical map 20; (3) Displaying real-time positions and orientations of a plurality of catheters within a heart chamber; and (4) displaying the region of interest where the ablation energy is applied, for example, on the display device 27. A commercial product embodying elements of system 10 is available from the Biosense Webster, inc.,31Technology Drive,Suite 200,Irvine,CA 92618,USA as a CARTO ^TM system.

The system 10 may also include a flush fluid system, and the workstation 55 may also be configured to deliver flush fluid to the catheter 14.

Fig. 2A is an illustration of a perspective view of a medical probe 22A including a basket assembly 100a in an expanded form when unconstrained. The medical probe 22a may be used in place of the catheter 14 shown in fig. 1. The distal portion of the sheath may include an insertion tube 60 (shown as transparent). The basket assembly 100a may traverse the lumen of the insertion tube 60 in a contracted state and may expand to an expanded form as shown when advanced beyond the distal end 66 of the insertion tube 60. Basket assembly 100a may be self-expanding such that ridges 214 expand away from longitudinal axis 86 upon exiting insertion tube 60 without requiring additional mechanisms such as push tubes or pull wires to expand basket assembly 100a to an expanded form. The ridges 214 form a support frame for the basket assembly 100a that provides the important structural and mechanical functions of the basket assembly 100 a.

The probe 22a may include a contact force sensor 400 to determine the contact force of the ridge 214 against heart tissue. Details of the contact force sensor 400 are shown and described in U.S. patent application publication No. US2021/0077180A1 published at 18, 3, 2021, the disclosure of which is incorporated herein by reference.

In the expanded form, the ridges 214 curve radially outward, while in the collapsed form (not shown), the ridges 214 are generally disposed along the longitudinal axis 86 of the insertion tube 60. Basket assembly 100a includes a plurality of electrically insulating sheaths 217 on each ridge 214 such that sheaths 217 are disposed between respective ridge 214 and respective electrode 40 to electrically insulate electrode 40 from ridge 214. For ease of illustration, a portion of the sheath 217 on one of the ridges 214 is omitted from the illustration of fig. 2A, and the basket assembly 100a preferably includes a sheath 217 on each ridge 214. Each electrode 40 may be positioned approximately in place relative to the ridge 214 by a retaining member 220 integrally formed with the ridge 214.

Ribs 214 may be attached to both ends of basket assembly 100a. During a medical procedure, medical professional 24 may deploy basket assembly 100a by extending tubular shaft 84 from insertion tube 60, causing basket assembly 100a to exit insertion tube 60 and transition to an expanded form. The ridges 214 may have a circular or oval cross-section, a square or rectangular cross-section, or other cross-sectional shape. The cross-sectional shape may appear flat. The ridge 214 may comprise a flexible, resilient material, for example a shape memory alloy, such as nickel-titanium, also known as nitinol. Basket assembly 100a has a proximal portion 36 and a distal portion 39a. The distal portion 39a of the support frame includes a clover-like distal structure 300, and thus the structure 300 will be referred to hereinafter as a "clover structure". The spine 214 extends along the longitudinal axis 86 from a proximal spine portion 216 to a distal spine portion that includes a clover configuration 300. The clover structure 300 is radially disposed about the longitudinal axis 86. The clover structure 300 defines a central cutout having a central region disposed about a longitudinal axis.

Preferably, the ridges 214 may be made of nitinol, cobalt chromium, stainless steel, titanium, combinations thereof, or alloys thereof. Each electrode 40 may be made of stainless steel, cobalt chromium, gold, platinum, palladium, and alloys thereof.

The medical probe 22a may include a ridge-retaining hub 90 extending longitudinally from the distal end of the tubular shaft 84 toward the distal portion 39a of the basket assembly 100 a. The ridge retention hub 90 may be inserted into the tubular shaft 84 and attached to the tubular shaft 84. The spine retention hub 90 may include a cylindrical member 94 that includes a plurality of relief grooves 96, a plurality of flushing openings 98 that allow flushing fluid to flow out into the volume defined by the basket spine, and a hub end 99. The workstation 55 may include a flush module that delivers flush fluid through the tubular shaft 84 to the basket assembly 100a and out of the flush opening 98 of the ridge retention hub 90. Relief grooves 96 may be provided on an outer surface of the cylindrical member 94 and configured to allow a portion of each ridge 214, such as each ridge attachment end 216, to fit into a corresponding relief groove 96 of the retention hub 90 (also referred to as a connector contacting the force sensor 400). The attachment end 216 may be a generally linear end of the ridge 214. The attachment end 216 may be configured to extend outwardly from the spine retention hub 90 such that the basket assembly 100a is positioned outwardly from the spine retention hub 90 and, thus, the tubular shaft 84. In this manner, the ridge 214 may be configured to position the basket assembly 100a away from the distal end of the tubular shaft 84 and away from the distal end of the insertion tube 60 when the basket assembly 100a is deployed. The reference electrode 95 may be disposed on the cylindrical member 94 or on the hub end surface 99. It should be noted that hub 90 may actually serve two functions: (1) holding the spine leg proximally; (2) Allowing hub 90 (and basket assembly 100 a) to be connected to distal tube 84; (3) As a fluid diverter for irrigation fluid delivered through distal tube 84; and (4) providing a reference electrode 95.

Basket assembly 100a includes atraumatic distal shroud 45a. Atraumatic distal cover 45a may be configured to reduce the likelihood of tissue damage due to pressure of distal portion 39a of basket assembly 100a against tissue. Atraumatic distal coverage 45a covers a majority of clover structure 300. As will be appreciated by those skilled in the art, in alternative configurations of basket assembly 100a, atraumatic distal cover 45a may be applied to the distal spine portion to reduce the likelihood of tissue damage due to pressure of distal portion 39a of basket assembly 100a against tissue. Atraumatic distal covering 45a may be particularly suited for basket assembly construction having struts or a structure having a rim positioned at the distal end of the basket assembly. Atraumatic distal covering 45a may comprise a central opening 47 about longitudinal axis 86. Atraumatic distal coverage 45a may comprise a flexible circuit with a sensor. Additionally or alternatively, atraumatic distal covering 45a may be constructed by dip coating clover structure 300.

Fig. 2B is an illustration of a tubular frame 110 of a medical probe formed from a tube blank. The tubular frame includes ridges 214 connected at a distal ridge by a clover structure 300 and connected at a proximal ridge by a proximal ring 112. The tubular frame 110 may be used in place of the ridge 214 shown in fig. 2A, with the retaining hub 90 modified to receive the proximal ring 112. Further, the ridges 214 of the tubular frame 110 may be modified to include the features of the ridges 214 shown in fig. 2A. Also within the scope of the present invention, the ridges 214 are formed from a flat blank, cut, and heat treated to obtain the spherical basket shape shown in fig. 2A. The tubular frame 110 of fig. 2B may be longitudinally compressed and the ridges 214 may radially expand to form a basket-like ridge structure similar to that shown in fig. 2A. Similarly, the ridges 214 shown in fig. 2A may be folded to align longitudinally as shown in fig. 2B. Similar to that shown in fig. 2A, tubular frame 110 includes atraumatic distal covering 45a over clover structure 300. The tubular frame 110 may serve as a support frame for a basket assembly similar to the basket assembly 100a shown in fig. 2A.

Fig. 2C is an illustration of a distal end view of the basket assembly 100a of fig. 2A. Sensor 150a may be coupled to atraumatic distal coverage 45a. For example, atraumatic distal coverage 45a may comprise a flex circuit, and sensor 150a may be patterned on the flex circuit. Atraumatic distal cover 45a is positioned on the distal surface of the support frame of basket assembly 100 a.

The sensor 150a may include a contact force sensor, an electrocardiogram sensor, and/or a position sensor. As shown, sensor 150a includes an induction coil that can be used as a single axis magnetic position sensor. The sensor 150a includes a circular portion 151 that includes a spiral inductor 152 and a linear portion 153 that includes a first conductive trace 154 from the outside of the spiral inductor 152 and a second conductive trace 155 from the inside of the spiral inductor 152. The linear portion 153 extends along the ridge 214 in a proximal direction to the shaft 84 to provide an electrical connection of the distal sensor 150b to the system 10 (fig. 1). For ease of illustration, the sensor 150a is shown to include only one spiral inductor 152, however, as will be appreciated by those skilled in the art, multiple spiral inductors of similar dimensions to the spiral inductor 152 shown may be stacked to increase the number of turns and thus increase the sensor sensitivity. For ease of illustration, the sheath 217 is omitted from some of the ridges 214 shown in fig. 2C. Preferably, each ridge 214 includes a sheath 217.

Fig. 3A is another illustration of a distal end view of the distal surface of basket assembly 100a of fig. 2A with atraumatic distal covering 45a removed for ease of illustration. The clover structure 300 is radially disposed about the longitudinal axis 86. The clover structure 300 includes clover cutouts 212. Each clover cutout 212 is aligned along radial axes A, B, C, D, E and F extending orthogonally to axis 86, such that the plurality of ridges 214 extend in an equiangular pattern such that the respective angles between respectively adjacent ridges are about equal. Although the preferred embodiment includes six ridges, it is within the scope of the invention to have any number of ridges from four to twelve.

Clover structure 300 defines a central cutout C0 having a negative or empty area A0 disposed about the longitudinal axis 86. The clover structure 300 is configured such that a portion of the clover structure 300 is tangential to the centre circle C0 near a position between any two radial axes where two adjacent ridges 214 lie. For example, where the ridge 214 is on the radius axis a and adjacent the ridge 214 is on the axis B, the clover structure 300 is tangent to the open circle C0 at a location bisecting the two radial axes a and B by a line Q1 connected to the central axis 86. This tangential nature of sinusoidal clover member 300 about open area A0 is repeated for any two adjacent ridges 214 (e.g., ridge 214 on axis B and ridge 214 on axis C, and so on) for all bisected axes Q1, Q2, Q3, Q4, Q5, and Q6. Bisecting axes Q1, Q2, Q3, Q4, Q5, and Q6 correspond to peaks of clover structure 300, and radial axes A, B, C, D, E and F correspond to valleys of the clover structure, with the peaks of the clover structure being closer to central axis 86 and Gu Gengyuan being away from central axis 86.

Fig. 3B shows an end view of basket assembly 100a shown in fig. 2A as if basket assembly 100a were separated from shaft 84 and distal portion 39a of basket assembly 100a was flattened between the two sheets of glass. The clover structure 300 may be sinusoidal, extending from one ridge 214 to an adjacent ridge 214 in a direction (e.g., counter-clockwise or clockwise) about the longitudinal axis 86. This characteristic of sinusoidal structure 300 can be seen in fig. 3B, where, for example, ridge 214 is positioned on radial axis a. Starting from this ridge 214 on axis a, clover structure 300 is configured such that it meanders around a portion of the incision 212 (as indicated by the dashed line) forming a sinusoidal member 302, the incision having a negative or open first area A1 that can be approximated by a circle R1. As used herein, the term "open area" means that there is no solid structure to define a space lacking framework material. The "open area" may be covered or at least partially filled with a second material, such as atraumatic distal cover 45 a. This first open area A1 is approximately 20% of the central area A0. For convenience, the first open area A1 may be approximated by a first virtual circle R1 that positions its center at a first distance L1 from the longitudinal axis 86. Continuing in fig. 4B, sinusoidal clover member 300 extends in a counter-clockwise direction from axis a about second open area A2 to axis F toward adjacent ridge 214 positioned on axis F. For convenience, the second open area A2 may also be approximated by a second virtual circle R2 having a second open area A2 of about 90% of the first open area A1. It should be noted that the second virtual circle may have its center of radius R2 positioned at a second distance L2 from the longitudinal axis 86 that is less than the first distance L1. Continuing toward axis F in fig. 4B, sinusoidal clover member 300 meanders along sinusoidal member 302 around a third open area A3, which is approximated for convenience by a third virtual circle having a radius R3. The third virtual circle has its center of radius R3 positioned at a third distance L3 from longitudinal axis 86 that is greater than L2 and approximately equal to first distance L1. Once the sinusoidal clover member 300 passes through the axis F, the structure naming is repeated again, wherein the other side of the axis F closer to the axis E has another first open area A1, on which side the clover structure 300 meanders towards the next ridge 214 positioned on the axis E, as indicated by the dashed line representing the sinusoidal member 302.

The width T0 of the ridge 214 may be 0.25mm to 1mm, while the sinusoidal member 302 has a maximum width T1 of about 1/2 of the width of T0 and a minimum width T2 of about 1/3 of the ridge width T0. The width T3 near the spine axis (A, B, C, D, E or F) is about the same as the maximum width T1. The central area A0 approximated by the radius R0 is about 0.8 square millimeters and the fourth virtual circle C4 may have an area that is about 14 times the central area A0. Each of the first and third virtual circles R1, R3 is positioned at a first distance L1 of about 1.5mm from the central axis 86, while the second virtual circle R2 is positioned at a distance L2 of about 1/2 of the first distance L1.

Fig. 3C shows another end view of basket assembly 100a shown in fig. 2A as if basket assembly 100a were separated from shaft 84 and distal portion 39a of basket assembly 100a was flattened between the two glass sheets. Fig. 3C illustrates selected dimensions of the clover structure 300, which may be tailored to achieve the desired mechanical properties of the basket assembly 100 a. The radius R1 of the first open area A1, the radius R2 of the second open area A2, the radius R3 of the third open area A3, and the minimum width T2 of the sinusoidal member 302 may each be adjusted to achieve desired mechanical properties. These dimensions are also shown in fig. 3B. In addition, the height H1 may be adjusted to achieve desired mechanical properties. The height H1 is measured from the innermost point of the second open area A2 to the neck 218, which is directly radially outward from the second open area A2 away from the longitudinal axis L-L. The neck 218 is positioned where adjacent proximal portions 306 of the clover structure 300 are closest to each other.

A second length L2 from the longitudinal axis L-L to the center of the second virtual circle A2 (fig. 3B) defines a boundary between the inner arc 304 and the outer portion 306 of the clover structure 300.

Fig. 4A is a perspective view of the distal portion 39a of the basket assembly 100a shown in fig. 2A to illustrate the concavity of the clover structure 300. For ease of illustration, the sheath 217 and the electrode 40 are omitted.

Fig. 4B is a side view of the distal portion 39a of the basket assembly 100a shown in fig. 2A to illustrate the concavity of the clover structure 300. For ease of illustration, the sheath 217 and the electrode 40 are omitted. The distal portion 39a of the basket assembly 100a may be shaped to have a curvature 305. As shown, the clover structure 300 is curved such that its open center 211 is contiguous with the plane defined by the central circle C0 and is spaced apart by a gap G relative to the plane defined by the fourth virtual circle C4 surrounding the clover structure 300. The concavity is represented by the dashed line of curvature 305, which may be an arcuate portion of a circle.

Fig. 5A shows a perspective view of another example medical probe 22b having an example basket assembly 100b that includes ridges 214, each of which includes closely spaced electrode pairs 40a, 40b and a sheath 217b extending over a proximal portion 306 (fig. 3C) of clover 300. The ridges 214 and basket assembly 100b may be configured in other ways similar to the basket assembly 100a shown in fig. 2A. The electrodes of each electrode pair 40a, 40b have an edge-to-edge spacing S1 between the electrodes of the electrode pair. The electrode pairs 40a, 40b are positioned in an alternating pattern with more distal electrode pairs 40a positioned on every other ridge 214 and more proximal electrode pairs 40b positioned on every other ridge 214. The basket assembly 100b defines an equator E1 perpendicular to the longitudinal axis 86, wherein the circumference of the basket shape is greatest. The proximal electrode pair 40b is completely proximal to the equator E1. The equator E1 crosses the proximal electrode of each of the distal electrode pairs 40 a.

Fig. 5B is a distal end view of basket assembly 100B shown in fig. 5A. The inner arc 304 of the clover structure 300 is exposed, while the outer portion 306 (fig. 3C) of the clover structure 300 is covered by the sheath 217b to provide the atraumatic distal section 39b of the basket assembly 100 b. Thus, the distal portion of sheath 217b forms an atraumatic structure that covers a portion of the clover structure. A second length L2 from the longitudinal axis L-L to the center of the second virtual circle A2 (fig. 3B) defines a boundary between the inner arc 304 and the outer portion 306 of the clover 300 (fig. 3C). A majority of each outer portion 306 (fig. 3C) is covered by a respective sheath 217 b. A substantial portion of the inner arc 304 is exposed to the environment. The distal portion of each sheath 217b tapers outwardly and inwardly along the curvature of the respective proximal portion 306 (fig. 3C) of the clover structure 300 covered by the sheath 271 a. When the basket assembly expands, the distal portions of each sheath 217b abut each other at the distal portion 39b of the basket assembly 100 b. The distal end of the sheath 271a can be heat set closed and/or heat fused. Additionally or alternatively, a small amount of polymer may be applied to the distal end of each sheath 217b to seal the sheath 217b to the ridge 214.

Fig. 5C shows a side view of two adjacent ridges 214 of basket assembly 100b shown in fig. 5A in a folded form for delivery. For simplicity of illustration, only two ridges 214 are shown. Each ridge 214 has a length L4 measured from the distal end 85 of the shaft 84 to the distal end of the clover 300 at the apex of the distal arc 304. The equator E1 is positioned approximately at the midpoint of the length L4 of the ridge 214. The electrode pairs 40a, 40b are positioned such that the electrode pairs 40a, 40b on adjacent ridges 214 do not overlap along the length L4 of the ridges 214. When basket assembly 38d is contracted for delivery, the electrodes of distal electrode pair 40a are fully distal to the electrodes of proximal electrode pair 40 b.

Basket assembly 100b may traverse the lumen of insertion tube 60 (fig. 2A) in a contracted state as shown in fig. 5C and may expand to an expanded form as shown in fig. 5A when advanced beyond distal end 66 of insertion tube 60 (fig. 2A). Basket assembly 100b may be self-expanding such that ridges 214 expand away from longitudinal axis 86 upon exiting insertion tube 60 (fig. 2A) without requiring additional mechanisms such as push tubes or pull wires to expand basket assembly 100b to an expanded form. The ridges 214 form a support frame for the basket assembly 100b that provides the important structural and mechanical functions of the basket assembly 100 b. The ridges 214 form a support frame for the basket assembly 100b that provides the important structural and mechanical functions of the basket assembly 100 b.

Fig. 6A is an illustration of an end planar view of the distal portion of the basket ridge structure of fig. 5A as if the entire basket ridge were captured flat between two flat glass plates for viewing by a viewer on the longitudinal axis. For ease of illustration, the sheath 217b is not shown on the exterior 306 of the clover structure 300. Basket assembly 100b includes a sensor 150b coupled to an exterior 306 of clover structure 300. The sensors 150b are each coupled to the distal surface of the support frame and are thus positioned in a distal direction relative to the distal surface of the support frame.

The distal portion of sheath 217b (fig. 5A) may be coupled to the sensor 150b and the exterior 306 of the clover structure 300, thereby forming an atraumatic structure on the sensor 150b and the exterior 306 of the clover structure 300. The distal portion 39b of the basket assembly 100b may include one or more sensors 150b. As shown in fig. 4B, clover structure 300 may include a curvature 305; in this case, the sensor 150b may have an axis that is not precisely aligned with the longitudinal axis. Depending on the degree of curvature 305, the sensor 150b may be considered to be generally aligned with the longitudinal axis and thus act collectively as a single axis sensor; or with a sufficient degree of curvature 305, the sensor 150b may collectively function as a two-axis sensor or a three-axis sensor.

Fig. 6B is an illustration of a distal sensor 150B that may be positioned on an exterior 306 of the clover structure 300 as shown in fig. 6A. Distal sensor 150b includes a circular portion 151b and a linear portion 153. The circular portion 151 includes a spiral inductor 152. The rounded portion is disposed on the distal surface of the support frame of basket assembly 100 a. The linear portion 153 includes a first conductive trace 154 from the outside of the spiral inductor 152b and a second conductive trace 155 from the inside of the spiral inductor 152. The linear portion 153 extends along the ridge 214 in a proximal direction to the shaft 84 to provide an electrical connection of the distal sensor 150b to the system 10 (fig. 1). For ease of illustration, the sensor 150 is shown to include only one spiral inductor 152, however, as will be appreciated by those skilled in the art, multiple spiral inductors of similar dimensions to the spiral inductor 152 shown may be stacked to increase the number of turns and thus increase the sensor sensitivity.

Fig. 7A is an illustration of a perspective view of another exemplary medical probe 22c including a basket assembly 100c in an expanded form when unconstrained, such as by being pushed out in the distal end 66 of the insertion tube lumen 60 (fig. 2A). The medical probe 22c may be configured similarly to the medical probe 22A, with the basket assembly 100a shown in fig. 2A replaced with the basket assembly 100c shown in fig. 7A. Basket assembly 100c includes a spine segment 214c that is retained by a retaining hub 180 at distal portion 39c of basket assembly 100c. The spine section 214c includes a spine ring that extends through the retention hub 180 and two proximal ends that are secured in the tubular shaft 84. Alternatively, the spine segment 214c may include separate spines, each having a respective distal end retained by the retention hub 180 and a respective proximal end secured in the tubular shaft 84. The distal hub 180 may be an atraumatic structure covering the distal portion of the spine segment 214c. The distal hub 180 is configured to maintain the relative position of the ridges 214 at the distal surface of the support frame.

The tubular shaft 84 is generally aligned along a longitudinal axis 86. The proximal end of the spine segment 214c may be configured similar to the proximal spine portion 216 shown in fig. 2A, may be coupled to the proximal ring 112 similar to that shown in fig. 2B, or otherwise secured to the tubular shaft 84.

Basket assembly 100c includes electrodes 40 on each of the spine segments 214c, each spine segment 214c having two electrodes. Electrode 40 may be positioned similar to electrode 40 shown in fig. 2A or similar to electrode 40b shown in fig. 5A. The spine segment 214c may be attached to the shaft 84 by a spine retention hub 90. The ridge retention hub 90 may include a flushing portion 98 and other features similar to the retention hub 90 shown in fig. 2A.

Basket assembly 100c may traverse the lumen of insertion tube 60 (fig. 2A) in a contracted state and may expand to an expanded form as shown in fig. 7A when advanced beyond distal end 66 of insertion tube 60 (fig. 2A). Basket assembly 100c may be self-expanding such that spine portion 214c expands away from longitudinal axis 86 upon exiting insertion tube 60 (fig. 2A) without requiring additional mechanisms such as push tubes or pull wires to expand basket assembly 100c to an expanded form.

The ridges 214 form a support frame for the basket assembly 100c that provides the important structural and mechanical functions of the basket assembly 100 c. The first portion 182 of the retention hub 180 is on the distal surface of the ridge 214 and thus on the distal surface of the support frame. The distal sensor 150c is thus also positioned in a distal direction relative to the distal surface of the support frame.

Fig. 7B is an illustration of a perspective view of the distal portion 39c of the medical probe 22c shown in fig. 7A. The retention hub 180 includes a first portion 182 positioned in a distal direction relative to the spine 214 and a second portion 186 positioned in a proximal direction relative to the first portion 182 such that the distal portion of the spine 214 is sandwiched between the first portion 182 and the second portion 186 of the retention hub 180. The protrusion 184 is positioned between distal portions of the ridge 214.

Fig. 7C is an illustration of the retention hub 180 shown in fig. 7A and 7B, with the first portion 182 separated from the second portion 186 and including the sensor 150C. The sensor 150c is coupled to the first portion such that the sensor 150c is positioned in a distal direction relative to the ridge 214. The sensor 150c may include a contact force sensor, an electrocardiogram sensor, and/or a position sensor. As shown, sensor 150c includes an induction coil that can be used as a single axis magnetic position sensor. The sensor 150c includes a circular portion 151 that includes a spiral inductor 152 and a linear portion 153 that includes a first conductive trace 154 from the outside of the spiral inductor 152 and a second conductive trace 155 from the inside of the spiral inductor 152. The linear portion 153 extends along the ridge 214 in a proximal direction to the shaft 84 to provide an electrical connection of the distal sensor 150b to the system 10 (fig. 1).

The spiral inductor 152 has an axis concentric with the longitudinal axis 86 (fig. 7A). For ease of illustration, the sensor 150c is shown to include only one spiral inductor 152, however, as will be appreciated by those skilled in the art, multiple spiral inductors of similar dimensions to the spiral inductor 152 shown may be stacked to increase the number of turns and thus increase the sensor sensitivity. Further, additional spiral inductors may be added to the retention hub 180 in the first portion 182 and/or the second portion 186, angled from the spiral inductor 152 shown, such that the sensor 150c in the retention hub 180 is modified to function as a two-axis sensor or a three-axis sensor.

Additionally or alternatively, the sensor 150c may be coupled to the second portion 186. Further, as will be appreciated by those skilled in the art, the sensor 150c may be similarly constructed by the sensors disclosed elsewhere herein, alternatives thereto, and variations thereof.

The second portion 186 of the retention hub 180 includes a recess 188 configured to receive the protrusion 184 extending in the proximal direction from the first portion 182 of the retention hub 180. The hub 180 is configured such that the ridge 214 can loop through the retention hub 180 between the protrusions 184, and the protrusions 184 engage the notches 188 to lock the first and second portions 182, 186 of the retention hub 180 together. As will be appreciated by those skilled in the art, the mechanical structure of the retention hub 180 may be modified in various ways to function as an atraumatic structure and include the distal sensor 150c.

The compatible features of each basket assembly 100, 100a, 100b, 100c disclosed herein are combinable. The electrodes 40, 40a, 40b may each include a body defining a hollow portion extending through the electrode body such that the ridge 214 may be inserted into the hollow portion and retained on the ridge 214. Each basket assembly 100, 100a, 100b, 100c may include an insulating cover over each ridge 214, such as the jackets 217, 217b shown herein, variations thereof, or alternatives thereof, to electrically insulate the ridges 214 from the electrodes 40, 40a, 40 b. Additionally or alternatively, at least a portion of the ridge 214 may be electrically conductive, and at least one of the electrodes 40, 40a, 40b may be electrically coupled to the conductive ridge 214. The ridge 214 of any of the basket assemblies 100, 100a, 100b, 100c may include a retaining member, such as the retaining member 220 shown in fig. 2A, and/or may include alternative means for coupling the electrodes 40, 40a, 40b to the ridge 214, such as glue, adhesive, welding, interference fit, or other mechanical structure. The electrodes 40, 40a, 40b of any of the basket assemblies 100, 100a, 100b, 100c may be configured to deliver an electrical pulse for IRE. These pulses may have a peak voltage of at least 900 volts (V). Further, IRE pulses may be delivered as described with respect to fig. 1, as disclosed elsewhere herein, as disclosed in publications incorporated by reference, or as understood by those of skill in the art. The ridges 214 may form an approximately spherical shape or an approximately oblate spherical shape when expanded in a basket-like configuration as shown in fig. 1, 2A, 5A, and 7A.

As understood by those skilled in the art, fig. 8A is a flow chart including steps in a method 460 of operation of the system 10 of fig. 1 using an exemplary basket catheter, such as the catheter 14 shown in fig. 1, variations thereof, or alternatives thereof. As will be appreciated by those of skill in the art, the catheter 14 may be configured similar to the exemplary medical probes 22a, 22b, 22c disclosed herein, variations thereof, or alternatives thereof.

At block 462, a position signal from a position sensor may be received. The workstation 55 (fig. 1) may be configured to receive a first position signal from a sensor 29 on the shaft 84 (hereinafter "shaft sensor 29") and a second position signal from a sensor positioned at a distal portion of the basket assembly 100. The shaft sensor 29 and the sensor positioned at the distal portion of the basket assembly may each comprise a magnetic sensor. The magnetic sensor of the shaft sensor 29 may provide one or more position signals corresponding to one or more coils of the sensor 29. Similarly, a magnetic sensor at the distal portion of basket assembly 100 may provide one or more position signals corresponding to one or more coils.

As will be appreciated by those of skill in the art, the basket assembly 100 may be configured similar to the basket assemblies 100a, 100b, 100c disclosed herein, variations thereof, or alternatives thereof. As will be appreciated by those skilled in the art, the distal portion of basket assembly 100 may be configured similar to the exemplary distal portions 39a, 39b, 39c disclosed herein, variations thereof, or alternatives thereof. As will be appreciated by those of skill in the art, the magnetic sensor at the distal portion of basket assembly 100 may be configured similar to distal sensor 150 (fig. 1), which may be configured similar to the exemplary distal sensors 150a, 150b, 150c disclosed herein, variations thereof, or alternatives thereof. As understood by those of skill in the art, the magnetic sensor of the distal sensor 150 may be coupled to atraumatic structures, such as the distal cover 45A shown in fig. 2A-2C, the distal portion of the sheath 217b shown in fig. 5A, the spine retention hub 180 shown in fig. 7A-7C, variations thereof, or alternatives thereof.

The shaft sensor 29 and the distal sensor 150 may each comprise a respective single-axis sensor (SAS), dual-axis sensor (DAS), or tri-axis sensor (TAS). The magnetic sensors of the shaft sensor 29 and the distal sensor 150 may be the same type of sensor, or different types of sensors. If the magnetic sensors of both the shaft sensor 29 and the distal sensor 150 are single axis sensors, the catheter 14 typically includes another position sensor to track the roll of basket assembly 100. The magnetic sensors of the shaft sensor 29 and the distal sensor 150 are configured 7 to output respective first and second position signals in response to a transmitted alternating magnetic field transmitted by one or more magnetic field generator coils 32 (fig. 1).

At block 464, position and orientation coordinates of the position sensor may be calculated. The calculation may be constrained by the calculated orientation coordinates of the first and second position sensors being equal. Workstation 55 may be configured to calculate position and orientation coordinates of shaft sensor 29 and distal sensor 150 based at least in part on the position signals received at block 462. Workstation 55 may be configured to use position calculations in which the position and orientation coordinates of the magnetic sensors of shaft sensor 29 and distal sensor 150 are calculated iteratively interdependently in response to the respective received position signals and constrained by the magnetic sensors comprising coaxial coils and thus having the same orientation. The coils of the sensors 29, 150a, 150b, 150c may be coaxial with the longitudinal axis 86.

Workstation 55 may be configured to calculate the position and orientation coordinates of the magnetic sensors (of shaft sensor 29 and distal sensor 150), subject to the constraint that the calculated orientation coordinates of the magnetic sensors will be equal within a given tolerance (such as plus or minus 2 degrees).

The steps of block 464 are described in more detail with reference to fig. 7B and 7C.

At block 466, workstation 55 may be configured to calculate a distance between the calculated position coordinates of the magnetic sensor of shaft sensor 29 and the calculated position coordinates of the magnetic sensor of distal sensor 150. As will be described in greater detail below with reference to the steps of block 470, the calculated distance is indicative of the curvature of the spine 214 and the general shape of the basket assembly 100.

At block 468, the workstation 55 may be configured to calculate a roll of the basket assembly 100 in response to one or more position signals from the magnetic sensor of the shaft sensor 29 and/or from the magnetic sensor of the distal sensor 150 and/or from another position sensor of the catheter 14. The sensors that provide data for computing the volume may include DAS or TAS.

The curvature of the spine 214 and/or the position of the electrode 40 (or other feature) on the spine 214 relative to a fixed point on the catheter 14 may be measured for various distances between the shaft sensor 29 and the magnetic sensor of the distal sensor 150. The fixation point may be located at the distal end 85 of the shaft 84, at the distal surface 99 of the spine retention hub 90 (fig. 2A), or other suitable location. For example, referring to fig. 2A, basket assembly 100a may be compressed by a longitudinal force applied to distal portion 39a along longitudinal axis 86, and the position of electrode 40 relative to a fixed point on catheter 14 may be measured for every 0.2mm movement of distal portion 39a relative to the fixed point, and after every 0.2mm movement, the calculated distance between shaft sensor 29 and the magnetic sensor of distal sensor 150a is recorded along with the position of electrode 40. The same technique may be applied to basket assemblies 100b, 100c shown in fig. 5A and 7A. This data may then be used to find the curvature of the spine 214 and/or the position of the electrode 40 (or other feature) on the spine 214 relative to a fixed point on the catheter 14 in response to the calculated distance between the magnetic sensors of the shaft sensor 29 and the distal sensor 150.

The curvature of the ridge 214 and/or the position of the electrode 40 (or other feature) on the ridge 214 relative to a fixed point on the catheter 14 may be calculated based on the calculated distance between the magnetic sensors of the shaft sensor 29 and the distal sensor 150 and a model of the catheter 14 that provides the curvature of the ridge 214 and/or the position of the electrode 40 for the calculated distance based on the mechanical properties and dimensions of the ridge 214.

At block 470, workstation 55 may be configured to estimate the respective positions of ridges 214 in response to the calculated distances, calculated volumes, and calculated position and orientation coordinates of one or more of the magnetic sensors of shaft sensor 29 and distal sensor 150. The calculated distance provides the corresponding position of the ridge 214 relative to the fixed point of the catheter 14. The calculated roll, position, and orientation coordinates of one or more of the magnetic sensors provide a corresponding position of the ridge 214 relative to a magnetic coordinate frame used in the system 10 (fig. 1).

At block 472, workstation 55 may be configured to present a representation 20 of at least a portion of catheter 14 and a body part (e.g., heart 26) to display 27 (fig. 1) in response to the estimated respective locations of ridges 214 and the calculated location of distal tip 28 of catheter 14 (e.g., based on one or more signals received from shaft sensor 29).

Fig. 8B is a flow chart of a method 474 including sub-steps in the operating method 460 of fig. 8A. The following sub-steps are sub-steps of the step of block 464 of fig. 8A.

At block 476, the position and orientation of a sensor may be calculated. Workstation 55 (fig. 1) may be configured to use position calculations to calculate position and orientation coordinates of one of the magnetic sensors of shaft sensor 29 or distal sensor 150 in response to one or more received signals of one sensor.

At block 478, the position coordinates of the other sensor may be calculated, subject to the constraint that the calculated orientation coordinates of the other sensor will be equal to the calculated orientation coordinates of the one sensor. The workstation 55 may be configured to calculate the position coordinates of the other sensor of the magnetic sensor using position calculations, subject to the constraint that the calculated orientation coordinates of the other sensor will be equal to the calculated orientation coordinates of one sensor within a given tolerance (such as plus or minus 2 degrees).

FIG. 8C is a flow chart including alternative sub-steps in the method of operation 480 of FIG. 8A; the following sub-steps are sub-steps of the step of block 464 of fig. 8A.

At block 482, an initial position and orientation of coordinates of both sensors 29, 150 may be calculated. Workstation 55 (fig. 1) may be configured to calculate initial positions and initial orientation coordinates of both the magnetic sensors of shaft sensor 29 and distal sensor 150 using position calculations.

At block 484, an average of the orientation coordinates may be calculated. Workstation 55 may be configured to calculate an average of the initial orientation coordinates of the magnetic sensor. For example, if the orientation coordinates are defined by two angles θ,Representing, for example, yaw and pitch, respectively, the orientation of the magnetic sensor of the axis sensor 29 is θA,And the orientation of the magnetic sensor of distal sensor 150 is θB,The average orientation of the magnetic sensor is equal to thetaav,Wherein θav is an average value of θA and θB, andIs thatAndAverage value of (2).

At block 486, coordinates of the two sensors may be calculated, subject to the constraint that the calculated orientation coordinates of the two sensors will be equal to the calculated average of the initial orientation coordinates. Workstation 55 may be configured to calculate the position and orientation coordinates of the magnetic sensors of shaft sensor 29 and distal sensor 150 using position calculations based on the signals received from sensors 29, 150, and constrained by the calculated average that the orientation coordinates of the two magnetic sensors will be equal to the initial orientation coordinates within a given tolerance (such as plus or minus 2 degrees).

Basket assembly 100 may also be deformed such that shaft sensor 29 and the magnetic sensor of distal sensor 150 are not coaxial. For example, a lateral force angled from the longitudinal axis 86 may be applied to a side or distal portion of the basket assembly 100 to deform the basket assembly 100 in an asymmetric manner to move the distal sensor 150 out of alignment with the longitudinal axis 86.

As will be appreciated by those skilled in the art, fig. 9 is a flow chart of steps in another method 510 that includes operation of the system 10 of fig. 1, using an exemplary basket catheter, such as the catheter 14 shown in fig. 1, variations thereof, or alternatives thereof. As will be appreciated by those of skill in the art, the catheter 14 may be configured similar to the exemplary medical probes 22a, 22b, 22c disclosed herein, variations thereof, or alternatives thereof.

At block 512, position signals may be received from the shaft sensor 29 and the position sensor of the distal sensor 150. Workstation 55 (fig. 1) may be configured to receive the first and second position signals from the magnetic sensors of shaft sensor 29 and distal sensor 150, respectively. In some embodiments, the magnetic sensor of the shaft sensor 29 may provide one or more position signals corresponding to one or more coils of the magnetic sensor. Similarly, the magnetic sensor of the distal sensor 150 may provide one or more position signals corresponding to one or more coils of the magnetic sensor.

At block 514, a distance between the sensors and one or more relative orientation angles may be calculated. The workstation 55 may be configured to calculate the distance and relative orientation angle between the magnetic sensors in response to the received position signals received at block 512. The relative orientation angle of a value greater than zero generally indicates that the basket assembly 100 is deflected to the side relative to the longitudinal axis 86 and that at least some of the ridges 214 twist as compared to the shape of the ridges 214 when the basket assembly 100 is positioned about the center of the longitudinal axis 86.

At block 516, a roll of basket assembly 100 may be calculated. The workstation 55 may be configured to calculate the roll of basket assembly 100 in response to one or more position signals from one or more of the magnetic sensors or from another sensor disposed on the catheter 14.

The curvature of the ridge 214 and/or the position of the electrode 40 (or other feature) on the ridge 214 relative to a fixed point on the catheter 14 may be measured for various distances between the magnetic sensors of the shaft sensor 29 and the distal sensor 150, as well as for various relative orientation angles between the magnetic sensors. The fixation point may be located at the distal end 85 of the shaft 84, at the distal surface 99 of the spine retention hub 90 (fig. 2A), or other suitable location. For example, the position of the electrode 40 relative to a fixed point on the catheter 14 may be measured for approximately every 0.2mm movement of the distal sensor 150 relative to the shaft 84 and for every 1 degree relative orientation between the shaft sensor 29 and the magnetic sensor of the distal sensor 150 (up to a maximum lateral movement of the basket assembly 100). At each different distance/relative orientation combination, the calculated distance and calculated relative orientation angle between the magnetic sensors of the shaft sensor 29 and the distal sensor 150 are recorded along with the position data of the electrode 40. This data may then be used to estimate the curvature of the spine 214 and/or the position of the electrode 40 (or other feature) on the spine 214 relative to a fixed point on the catheter 14 in response to the calculated distance and relative orientation angle between the magnetic sensors of the shaft sensor 29 and the distal sensor 150.

Additionally or alternatively, the curvature of the ridge 214 may be estimated based on the following assumptions: (a) Each of the ridges 214 has a fixed and known length; (b) Each ridge 214 is coupled symmetrically about the longitudinal axis 86 at the distal end of the basket assembly such that the distal sensor 150 is substantially perpendicular (within plus or minus 10 degrees of error) to the longitudinal axis 86 with distal coupling members (e.g., clover structure 300, retention hub 180, etc.); (c) Each ridge 214 is connected to the shaft 84 substantially parallel (within plus or minus 10 degrees of error) to the longitudinal axis 86 (e.g., ridge-retaining hub 90, etc.). Based on the assumptions (a) - (c) above, and the calculated positions of the coupling members based on the calculated positions of the magnetic sensors of the shaft sensor 29 and the distal sensor 150, the curvature of each of the ridges 214 may be calculated using a cubic polynomial. In some embodiments, the curvature of the spine 214 and/or the position of the electrode 40 (or other feature) on the spine 214 relative to a fixed point on the catheter 14 may be calculated based on the calculated distance between the magnetic sensors of the shaft sensor 29 and the distal sensor 150 and a model of the catheter 14 that provides the curvature of the spine 214 and/or the position of the electrode 40 for the calculated distance based on the mechanical characteristics and dimensions of the spine 214.

At block 518, the respective locations of the ridges 214 may be estimated in response to at least the calculated distance, one or more relative orientation angles, and the roll. Workstation 55 may be configured to estimate the respective positions of ridges 214 in response to at least the calculated distance and relative orientation angle, while accounting for distortion of one or more of ridges 214 from a symmetrical arrangement about longitudinal axis 86 when the value of the relative orientation angle of distal sensor 150 with respect to longitudinal axis 86 of shaft sensor 29 is greater than zero. The calculated distance and relative orientation angle between the magnetic sensors of the shaft sensor 29 and the distal sensor 150 provide the corresponding position of the ridge 214 relative to the fixed point of the catheter 14. The calculated roll, position, and orientation coordinates of one or more of the magnetic sensors of the shaft sensor 29 and the distal sensor 150 provide the respective positions of the ridges 214 relative to the magnetic coordinate frame used in the system 10 (fig. 1).

At block 520, a representation of at least a portion of the catheter 14 and a body part may be presented. Workstation 55 may be configured to present a representation 20 of at least a portion of catheter 14 and a body part (e.g., heart 26) to display 27 (fig. 1) in response to the estimated respective positions of ridges 214 and the calculated position of shaft 84 (e.g., based on one or more signals received from a magnetic sensor of shaft sensor 29).

Having shown and described exemplary embodiments of the subject matter contained herein, further modifications may be made to achieve the methods and systems described herein without departing from the scope of the claims. Furthermore, where methods and steps described above represent specific events occurring in a particular order, it is contemplated herein that certain specific steps need not necessarily be performed in the order described, but may be performed in any order, provided that the steps enable an embodiment to achieve its intended purpose. Therefore, this patent is intended to cover such modifications as well, if they come within the spirit and scope of the present disclosure or equivalents as found in the claims. Many such modifications will be apparent to those skilled in the art. For example, the examples, embodiments, geometries, materials, dimensions, ratios, steps, and the like described above are illustrative. Therefore, the claims should not be limited to the exact details of construction and operation shown in the written description and drawings.

The following clauses list non-limiting embodiments of the present disclosure:

Clause 1, end effector of a catheter, the end effector comprising: a support frame including a plurality of ridges configured to self-expand from a proximal portion to a distal ridge portion away from the longitudinal axis to form a basket-like configuration, the distal ridge portion defining a clover structure disposed radially about the longitudinal axis, the clover structure defining a central cutout having a central region disposed about the longitudinal axis, the clover structure including an inner arc defining a concave perimeter about the longitudinal axis; an atraumatic structure covering a portion of the clover structure of the support frame such that an inner arc of the clover structure extending only towards the proximal portion is visible.

Clause 2. The end effector of clause 1, further comprising: a sensor coupled to the atraumatic structure; and a plurality of electrodes coupled to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges.

Clause 3 the end effector of clause 2, wherein the sensor is disposed in a distal direction relative to the distal surface of the support frame in the basket configuration.

Clause 4. The end effector of clause 2 or 3, the sensor comprising a contact force sensor.

Clause 5 the end effector of any of clauses 2-4, the sensor comprising an electrocardiogram sensor.

Clause 6 the end effector of any of clauses 2-5, the sensor comprising a position sensor.

Clause 7. The end effector of clause 6, the position sensor comprising an induction coil.

Clause 8 the end effector of clause 6 or 7, the position sensor comprising a magnetic sensor.

Clause 9 the end effector of any of clauses 6-8, the position sensor comprising a single axis sensor comprising a sensor axis coaxial with the longitudinal axis.

Clause 10 the end effector of clause 9, wherein the atraumatic structure comprises a flexible circuit.

Clause 11 the end effector of clause 10, wherein the flexible circuit comprises a rounded portion covering the distal surface of the support frame to form an atraumatic covering on the distal surface of the support frame, and an elongated portion extending proximally along one of the plurality of ridges.

Clause 12 the end effector of clause 10 or 11, wherein the single axis sensor comprises a spiral conductor embedded in a circular portion of the flexible circuit.

Clause 13 the end effector of any of clauses 10-12, wherein the support frame comprises a distal structure connecting the ridges and defining a central incision having a central region disposed about the longitudinal axis, the atraumatic structure covering at least a portion of the central incision.

Clause 14 the end effector of clause 13, wherein the distal structure comprises a sinusoidal member extending from one ridge to an adjacent ridge in a direction about the longitudinal axis and forming a clover structure.

Clause 15 the end effector of any of clauses 1-9, further comprising: a plurality of sheaths over the plurality of ridges.

Clause 16 the end effector of clause 15, wherein the plurality of sheaths extends over a majority of the clover structure such that the atraumatic structure comprises a respective distal portion of each sheath of the plurality of sheaths.

Clause 17 the end effector of clause 15 or 16, wherein the inner arc extends from the distal ends of the plurality of sheaths and between adjacent sheaths of the plurality of sheaths.

Clause 18 the end effector of any of clauses 15-17, further comprising: a plurality of electrodes positioned in pairs such that each ridge includes a respective pair of electrodes and such that the pair of electrodes of a ridge does not longitudinally overlap the pair of electrodes of an adjacent ridge.

Clause 19 the end effector of any of clauses 1-18, wherein each electrode comprises a body defining a hollow portion extending through the body of the electrode such that the ridge can be inserted into the hollow portion and retained on the ridge.

Clause 20 the end effector of clause 19, wherein each ridge comprises a retaining member configured to be compressed to allow the electrode to move on the retaining member, and to expand to inhibit the electrode from moving along the ridge.

Clause 21 the end effector of any of clauses 1-20, wherein the plurality of electrodes are configured to deliver an electrical pulse for irreversible electroporation, the pulse comprising a peak voltage of at least 900 volts (V).

Clause 22 the end effector of any of clauses 1-21, wherein the plurality of ridges are configured to form an approximately spherical basket assembly when in a basket configuration.

Clause 23 the end effector of any of clauses 1-22, wherein the plurality of ridges are configured to form an approximately oblate spheroid basket assembly when in the basket configuration.

Clause 24, an end effector of a catheter, the end effector comprising: a support frame comprising a plurality of ridges configured to expand away from the longitudinal axis to form a basket-like configuration; an atraumatic structure coupled to the plurality of ridges at a distal end of the support frame; a sensor coupled to the atraumatic structure and positioned distally of the support frame; and a plurality of electrodes coupled to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges.

Clause 25 the end effector of clause 24, wherein the atraumatic structure comprises a rigid electrically insulating structure.

Clause 26 the end effector of clause 24 or 25, wherein the atraumatic structure is configured to maintain the relative position of the ridges of the plurality of ridges at the distal surface of the support frame.

Clause 27 the end effector of any of clauses 24-26, wherein the sensor comprises a single axis sensor, a dual axis sensor, and/or a tri-axis sensor.

Clause 28 the end effector of any of clauses 24-27, the sensor comprising a contact force sensor.

Clause 29 the end effector of any of clauses 24-28, wherein the sensor comprises an electrocardiogram sensor.

Clause 30 the end effector of any of clauses 24-29, the sensor comprising a position sensor.

Clause 31 the end effector of clause 30, the position sensor comprising an induction coil.

Clause 32 the end effector of clause 30 or 31, the position sensor comprising a magnetic sensor.

Clause 33 the end effector of any of clauses 30-32, the position sensor comprising a single axis sensor comprising a sensor axis coaxial with the longitudinal axis.

Clause 34 the end effector of any of clauses 24-33, wherein each electrode comprises a body defining a hollow portion extending through the body of the electrode such that the ridge can be inserted into the hollow portion and retained on the ridge.

Clause 35 the end effector of clause 34, wherein each ridge comprises a retaining member configured to be compressed to allow the electrode to move on the retaining member, and the retaining member is configured to expand to inhibit the electrode from moving along the ridge.

The end effector of any one of clauses 24-35, wherein the plurality of electrodes are configured to deliver an electrical pulse for irreversible electroporation, the pulse comprising a peak voltage of at least 900 volts (V).

Clause 37 the end effector of any of clauses 24-36, wherein the plurality of ridges are configured to form an approximately spherical basket assembly when in a basket configuration.

Clause 38 the end effector of any of clauses 24-37, wherein the plurality of ridges are configured to form an approximately oblate spheroid basket assembly when in the basket configuration.

Clause 39, a system comprising: a catheter configured to be inserted into a body part of a living subject, the catheter comprising a shaft including a coil-based first position sensor disposed near a distal end of the shaft, and a basket assembly including a self-expanding support frame and a coil-based second position sensor coupled to the distal end of the self-expanding support frame, and further including a plurality of electrodes coupled to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges; at least one magnetic field radiator configured to transmit an alternating magnetic field into an area in which the body part is located, the first and second position sensors being configured to output respective first and second position signals in response to the transmitted alternating magnetic field; and processing circuitry configured to: receiving a first position signal and a second position signal from a first position sensor and a second position sensor; calculating position and orientation coordinates of the first and second position sensors using position calculations, wherein the position and orientation coordinates of each of the position sensors are iteratively calculated in dependence upon each other in response to the respective received position signals and constrained by the first and second position sensors being coaxial; calculating a distance between the calculated position coordinates of the first position sensor and the calculated position coordinates of the second position sensor; respective locations of the plurality of ridges are estimated in response to at least the calculated distances.

Clause 40, a system comprising: a catheter configured to be inserted into a body part of a living subject, the catheter comprising a shaft including a coil-based first position sensor disposed near a distal end of the shaft, and a basket assembly including a self-expanding support frame and a coil-based second position sensor coupled to the distal end of the self-expanding support frame, and further including a plurality of electrodes coupled to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges; at least one magnetic field radiator configured to transmit an alternating magnetic field into an area in which the body part is located, the first and second position sensors being configured to output respective first and second position signals in response to the transmitted alternating magnetic field; and processing circuitry configured to: receiving a first position signal and a second position signal from a first position sensor and a second position sensor; calculating a distance and a relative orientation angle between the first position sensor and the second position sensor in response to the received position signals; respective positions of the plurality of ridges are estimated in response to at least the calculated distance and the relative orientation angle, while taking into account a distortion of one or more of the plurality of ridges from the symmetrical arrangement when the value of the relative orientation angle is greater than zero.

Clause 41 the system of clause 39 or 40, the coil-based second position sensor is disposed in a distal direction relative to the distal surface of the self-expanding support frame.

Clause 42. A method comprising: inserting a catheter into a body part of a living subject, the catheter including a shaft and a basket assembly including a self-expanding support frame and a coil-based first position sensor coupled to the distal end of the self-expanding support frame, the basket assembly further including a plurality of electrodes coupled to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges; exposing the basket assembly to allow the self-expanding support frame to form a basket shape; transmitting an alternating magnetic field into an area in which the body part is located; outputting, by the first and second position sensors, respective first and second position signals in response to the transmitted alternating magnetic field; receiving a first position signal and a second position signal from a first position sensor and a second position sensor; calculating position and orientation coordinates of the first and second position sensors using position calculations, wherein the position and orientation coordinates of each of the position sensors are iteratively calculated in dependence upon each other in response to the respective received position signals and constrained by the first and second position sensors being coaxial; calculating a distance between the calculated position coordinates of the first position sensor and the calculated position coordinates of the second position sensor; the respective locations of the ridges are estimated in response to at least the calculated distances.

Clause 43, a method comprising: inserting a catheter into a body part of a living subject, the catheter including a shaft and a basket assembly including a self-expanding support frame and a coil-based first position sensor coupled to the distal end of the self-expanding support frame, the basket assembly further including a plurality of electrodes coupled to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges; exposing the basket assembly to allow the self-expanding support frame to form a basket shape; transmitting an alternating magnetic field into an area in which the body part is located; outputting, by the first and second position sensors, respective first and second position signals in response to the transmitted alternating magnetic field; receiving a first position signal and a second position signal from a first position sensor and a second position sensor; calculating a distance and a relative orientation angle between the first position sensor and the second position sensor in response to the received position signals; the respective positions of the ridges are estimated in response to at least the calculated distance and the relative orientation angle while taking into account a distortion of one or more of the plurality of ridges from the symmetrical arrangement when the value of the relative orientation angle is greater than zero.

Clause 44. A method of constructing a medical probe, the method comprising: forming a support frame comprising a plurality of ridges; configuring the plurality of ridges to be positioned about the longitudinal axis and self-expandable away from the longitudinal axis; covering the distal surface of the support frame with an atraumatic structure; coupling a sensor to the atraumatic structure; and coupling the plurality of electrodes to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges.

Clause 45 the method of clause 44, wherein the support frame comprises a distal structure connecting the ridges and defining a central cutout having a central region disposed about the longitudinal axis, the central cutout defining an opening in the distal surface of the support frame.

Clause 46 the method of clause 45, wherein forming the support frame from the plurality of ridges comprises cutting the tube such that the distal structure surrounds the tube and the plurality of ridges extend longitudinally along the tube.

Clause 47 the method of clause 44, further comprising: the distal portions of the plurality of ridges are coupled with the atraumatic structure.

Clause 48 the method of clause 47, wherein the sensor is embedded in the atraumatic structure.

Clause 49. A method of constructing a medical probe, the method comprising: inserting a plurality of ridges into a plurality of sheaths such that the plurality of ridges extend along a longitudinal axis from a proximal central proximal ridge portion to a distal ridge portion, the distal ridge portion defining a clover structure disposed radially about the longitudinal axis, the clover structure defining a central cutout having a central region disposed about the longitudinal axis, and such that the plurality of sheaths each cover a majority of the distal ridge portion; aligning a plurality of ridges with a plurality of electrodes, each electrode having a lumen extending through the electrode body; inserting each ridge of the plurality of ridges into a lumen of an electrode of the plurality of electrodes; and holding the plurality of electrodes on the plurality of ridges.

Clause 50 the method of clause 49, wherein holding the plurality of electrodes on the plurality of ridges comprises holding one of the plurality of electrodes with at least one biasing member.

Clause 51 the method of clause 50, wherein the at least one biasing member is disposed outside the lumen of the electrode.

Clause 52 the method of clause 50, wherein the at least one biasing member is disposed within the lumen of the electrode.

Clause 53 the method of clause 49, further comprising: positioning the wire through the lumen of the electrically insulating sheath; positioning one of the plurality of electrodes on the electrically insulating sheath; and electrically connecting the lead wire to the electrode through the aperture in the electrically insulating sheath.

Clause 54 the method of clause 49, wherein each respective ridge of the plurality of ridges comprises a first electrode and a second electrode, the method further comprising: aligning each respective ridge of the plurality of ridges with the first electrode and the second electrode; inserting each respective ridge of the plurality of ridges into the lumen of the first electrode and the lumen of the second electrode; and fitting an end of each respective ridge of the plurality of ridges to a tubular shaft sized to traverse the vasculature.

Clause 55 the method of any of clauses 49 to 54, further comprising offsetting the electrodes between adjacent ridges along the longitudinal axis.

The method of any of clauses 49-54, wherein the electrode body lumen is configured to receive a guidewire of a medical probe.

Clause 57 the method of any of clauses 49 to 56, wherein the wire is insulated from the ridge.

Clause 58 an end effector of a catheter, the end effector comprising: a support frame including a plurality of ridges configured to self-expand away from the longitudinal axis from a proximal portion to a distal ridge portion to form a basket-like configuration, the distal ridge portion defining a clover structure disposed radially about the longitudinal axis, the clover structure defining a central cutout having a central region disposed about the longitudinal axis; a plurality of jackets over a majority of the plurality of ridges and clover structures; and a plurality of electrodes each coupled to a respective ridge of the plurality of ridges.

Clause 59 the end effector of clause 58, further comprising: a plurality of sensors, each sensor disposed between a respective sheath of the plurality of sheaths and the clover structure.

Clause 60 the end effector of clause 59, wherein the plurality of sensors comprises inductive sensors.

Clause 61 the end effector of clause 58 or 59, wherein the plurality of sensors are configured to collectively function as a tri-axial sensor.

Claims

1. An end effector of a catheter, the end effector comprising:

A support frame comprising a plurality of ridges configured to self-expand from a proximal portion to a distal ridge portion away from a longitudinal axis to form a basket-like configuration, the distal ridge portion defining a clover structure disposed radially about the longitudinal axis, the clover structure defining a central cutout having a central region disposed about the longitudinal axis, the clover structure comprising an inner arc defining a concave perimeter about the longitudinal axis; and

An atraumatic structure covering a portion of the clover structure of the support frame such that an inner arc of the clover structure extending only towards the proximal portion is visible.

2. The end effector of claim 1, further comprising:

A plurality of sheaths over the plurality of ridges, wherein the plurality of sheaths extend over a majority of the clover structure such that the atraumatic structure comprises a respective distal portion of each sheath of the plurality of sheaths.

3. The end effector of claim 2, wherein the inner arc extends from a distal end of the plurality of sheaths and between adjacent sheaths of the plurality of sheaths.

4. The end effector of claim 2, further comprising:

A sensor disposed between the clover structure and a distal portion of a sheath of the plurality of sheaths; and

A plurality of electrodes coupled to the plurality of ridges such that respective ones of the plurality of electrodes are coupled to respective ones of the plurality of ridges.

5. The end effector of claim 4, wherein in the basket configuration, the sensor is disposed in a distal direction relative to a distal surface of the support frame.

6. The end effector of claim 4, the sensor comprising a contact force sensor.

7. The end effector of claim 4, the sensor comprising a position sensor.

8. The end effector of claim 7, the position sensor comprising an induction coil.

9. The end effector of claim 7, the position sensor comprising a magnetic sensor.

10. The end effector of claim 1, further comprising:

A plurality of electrodes positioned in pairs such that each ridge includes a respective electrode pair and such that the respective electrode pair of a ridge does not longitudinally overlap the electrode pair of an adjacent ridge.

11. The end effector of claim 10,

Wherein the plurality of electrodes includes a proximal electrode pair and a distal electrode pair such that the proximal electrode pair and the distal electrode pair are positioned in an alternating manner on the plurality of ridges, and

Wherein the pair of proximal electrodes is entirely proximal to an equator of the basket-like configuration.

12. The end effector of claim 10, wherein each electrode of the plurality of electrodes comprises a body defining a hollow portion extending through the body of the electrode such that a ridge can be inserted into the hollow portion and retained on the ridge.

13. The end effector of claim 12, wherein each ridge comprises a retaining member configured to be compressed to allow movement of an electrode on the retaining member, and the retaining member is configured to expand to inhibit movement of the electrode along the ridge.

14. The end effector of claim 10, wherein the plurality of electrodes are configured to deliver an electrical pulse for irreversible electroporation, the electrical pulse having a peak voltage of at least 900 volts (V).

15. The end effector of claim 1, wherein the plurality of ridges are configured to form an approximately spherical basket assembly when in the basket configuration.

16. The end effector of claim 1, wherein the plurality of ridges are configured to form an approximately oblate spheroid basket assembly when in the basket configuration.

17. An end effector of a catheter, the end effector comprising:

A support frame comprising a plurality of ridges configured to self-expand away from a longitudinal axis from a proximal portion to a distal ridge portion to form a basket-like configuration, the distal ridge portion defining a clover structure disposed radially about the longitudinal axis, the clover structure defining a central cutout having a central region disposed about the longitudinal axis;

a plurality of jackets over the plurality of ridges and a majority of the clover structure; and

A plurality of electrodes each coupled to a respective ridge of the plurality of ridges.

18. The end effector of claim 17, further comprising:

a plurality of sensors, each sensor disposed between a respective sheath of the plurality of sheaths and the clover structure.

19. The end effector of claim 18, wherein the plurality of sensors comprises inductive sensors.

20. The end effector of claim 18, wherein the plurality of sensors are configured to collectively function as a tri-axial sensor.