A catheter may include an elongate body extending from a proximal end to a distal end and defining a lumen; a push member mechanically coupled to the proximal end of the elongate body; and a slidable push grip disposed about an outer perimeter of the push member. The slidable push grip is controllably engageable with the push member. When the slidable push grip is in an engaged state with the push member, the slidable push grip transmits an axial force to the push member to enable the push member to transmit the axial force to the elongate body. When the slidable push grip is in a disengaged state with the push member, the slidable push grip is movable axially in at least one direction along a length of the push member while transmitting substantially no axial force to the push member.

A steerable catheter system may include a flexible elongate catheter body, a drive mechanism at the proximal end of the catheter body, and at least one group of pullwires extending along a length of the catheter body. The catheter body may include a distal articulating section and a proximal non-articulating section. Each group of pullwires includes at least two pullwires, and each of the pullwires is anchored at a first end to the distal end of the catheter body and at a second end to the drive mechanism. The pullwires of each group are positioned close to one another in the catheter wall to concentrate the forces and cause deflection along the articulating section of the catheter body and diverge away from one another to reach a more separated distribution around a circumference of the catheter body to distribute the forces and prevent deflection along the non-articulating section.

Steerable catheters are provided, some of which include an axial member incorporated in an elongate shaft member, where, in some instances, different edge portions of the axial member exhibit different radii of curvature. In some instances, a furthest-apart pair of points on an external boundary of a cross-section of the axial member is closer to an interior edge than an exterior edge of a tubular member of the elongate shaft member.

A delivery system for prosthetic heart valves are provided. The delivery system includes a flexible shaft, a distal sheath capsule configured to contain the prosthetic heart valve, an inner steerable catheter including an inner distal flex component, and an outer steerable catheter including an outer distal flex component. The inner distal flex component includes a first cut pattern and a second cut pattern distal to the first cut pattern. The outer distal flex component includes a third cut pattern. The inner steerable catheter is rotatable at least 90 degrees relative to the outer steerable catheter when the third cut pattern of the outer distal flex component is disposed over at least a portion of the first cut pattern of the inner distal flex component and each of the inner steerable catheter and the outer steerable catheter is in the flexed configuration.

A steerable catheter may include an elongate shaft member and a braided reinforcement structure embedded into a wall of the elongate shaft member. The braided reinforcement structure may include a first braided portion including a first pick count, a second braided portion including a second pick count, and a third braided portion including a third pick count. The third pick count may be greater than each of the first pick count and the second pick count.

A catheter can have a distal circular region that can contract in circumference via manipulation of a pull wire. The circular region can have electrodes distributed around the circumference that are suitable for mapping and/or ablation, and preferably suitable for IRE ablation. The catheter can include a cross-over region near a distal end of a shaft in which elongated elements extend at an angle to the longitudinal axis. The cross-over region can be bounded by an intermediate tube having four lumens and a distal tube having three lumens. The circular region can include structural features to facilitate contraction such as a support member having a preferable bending direction, polymer tubing segments positioned to inhibit bending stress on electrodes, navigation sensors positioned to inhibit bending stress on said sensors and electrodes, and a distal assembly at a distal end of the circular region.

Disclosed herein are methods to restore myocardial conduction via the injection of conductive nanoparticles into the myocardium via an endovascular injection catheter.

An active return curve deflectable catheter includes an elongate member, a fixation member, a deflection assembly, and a pull wire. The fixation member is coupled to a distal portion of the elongate member. The deflection assembly includes a hub assembly coupled to a proximal end of the elongate member, a handle, and a control member. The pull wire extends from the control member through the hub assembly to the fixation member. The elongate member is configured to deflect from an initial configuration to a deflected configuration in response to a pull force applied to the pull wire by actuation of the control member in a first direction.

A deflectable catheter includes an elongate member having a wall defining a longitudinally extending lumen extending from a proximal end to a distal end, a fixation member coupled to an exterior surface of the wall on a distal portion of the elongate member, and a pull wire extending through the wall of the elongate member from the proximal end of the elongate member to the fixation member. The pull wire is coupled to the fixation member and constrained along its length such that the elongate member is configured to deflect from an initial configuration to a deflected configuration in response to a pull force applied to the pull wire and actively return from the deflected configuration to the initial configuration in response to a push force applied to the pull wire.

A sheath, including a sheath body, a handle, and a traction wire. The traction wire includes a first traction wire. The handle includes a first guide rail member and a first slider. The first slider is connected to the first traction wire. A first groove is provided on an outer wall of the first guide rail member along an axial direction. The first groove includes a first bottom and a first side wall. The first slider slides in the first groove along the first side wall so as to drive the first traction wire to move. At least part of the outer wall of the first guide rail member is radially recessed to a central shaft of the first guide rail member to form the first groove.