An expandable medical sheath can include a sheath body having a lumen that extends between proximal and distal ends of the sheath. The sheath can have first and second members where the first member has a different elastic modulus than the second member such that one provides elasticity to the sheath and the other provides column strength. The first and second members can be coupled together in alternating sections to form the tubular sheath or the stiffer members can be embedded in the elastic member along all or a portion of the longitudinal length of the sheath. The sheath can automatically move to an expanded state to allow a larger diameter medical device to pass through the lumen, and once through the sheath can automatically return to its initial diameter.

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.

A medical assembly includes an expandable-mouth catheter and an introducer tool configured to facilitate advancement of the catheter into a delivery sheath. In some examples, a distal-most portion of the introducer tool includes a plurality of axial extensions separated by triangular-shaped slits. When the catheter is received within the introducer tool and when the introducer tool is received within a tapered portion of the delivery sheath, the axial extensions are configured to collapse radially inward to radially compress the expandable member and to enable the introducer to extend farther into the delivery sheath.

A steerable catheter includes a catheter shaft having a lumen defined by a catheter wall, a proximal portion, a distal portion, and a length extending therebetween, and at least one pullwire extending along the length of the catheter shaft and coupled to the catheter wall. The at least one pullwire has a proximal section extending along the proximal portion of the catheter shaft in a first radial position, a distal section extending along the distal portion of the catheter shaft in a second radial position, and a transition zone connecting the proximal section and the distal section. The second radial position is offset circumferentially from the first radial position.

A guide extension catheter includes a push member and a distal shaft coupled to and extending distally from the push member. The distal shaft includes a shaft wall and a passageway. The shaft wall includes a helically-shaped proximal end and a distal end. The helically-shaped proximal end coils helically about a first central longitudinal axis of the passageway of the distal shaft. The helically-shaped proximal end of the shaft wall defines a helically-shaped entry port of the distal shaft. The distal shaft may include a helically-shaped collar coupled to the helically-shaped proximal end of the distal shaft, the collar defining the helically-shaped entry port of the distal shaft.

A double-balloon catheter device for gastrointestinal anastomosis. The double-balloon catheter device for gastrointestinal anastomosis includes a liquid injection assembly, a double-balloon assembly, and a supporting device (15) connecting the liquid injection assembly and the double-balloon assembly. The liquid injection assembly includes a first balloon liquid injection connection port (2), a guide wire connection port (3), and a second balloon liquid injection connection port (4). The double-balloon assembly includes a double-balloon catheter device (5), and includes a first balloon (6) and a second balloon (7) that can expand-and that are respectively disposed on the two ends of the double-balloon catheter device (5). The double-balloon catheter device (5) is provided with a first balloon liquid injection channel (51), a guide wire channel (52), and a second balloon liquid injection channel (53).

An stent delivery system may include a delivery device and a tubular body having a lumen sized to slidably fit about an outer diameter of the delivery device and a drainage stent having an anchoring mechanism, wherein the delivery device includes a constraining member configured to engage an external portion of the tubular body at the proximal end of the delivery device. A method of delivering a stent may include inserting a tubular body into the port of an endoscope, inserting a stent delivery device and a stent having an anchoring mechanism into the tubular body, wherein the delivery device includes a constraining member configured to engage and retain the tubular body at the proximal end of the delivery device, advancing the drainage stent distally through the tubular body, sliding the tubular body proximally, and engaging an external portion of the tubular body with the constraining member.

An instrument delivery device may include a housing, which may include a proximal end, a distal end, and a slot. The instrument delivery device may include an advancement element extending through the slot and configured to move linearly along the slot. The instrument delivery device may include a guidewire, which may include a first end and a second end. In response to movement of the advancement element distally a first distance along the slot, the second end of the guidewire may be configured to advance a second distance. The second distance may be at least twice the first distance. The instrument delivery device may include a tubing, which may include a distal end and a proximal end. In response to movement of the advancement element distally the first distance along the slot, the proximal end of the tubing may be configured to advance the first distance.

A delivery catheter as disclosed herein may be configured in various embodiments to minimize the potential for entanglement between cardiac repair components such as between sutures and coupled anchors. In various embodiments this is achieved by separating an anchor translation channel from a suture translation channel while maintaining the coupling between the anchor and the suture.

In some examples, a catheter may include an elongate body and a push assembly. The elongate body may include an inner liner defining an entry port into a lumen defined by the elongate body, and an outer jacket. The push assembly may an anchor member positioned at a distal end of an elongate member. Distal to a proximal end of the elongate body, a first portion of the push assembly, comprising the anchor member, may be positioned between a portion of the inner liner and a portion of the outer jacket. The anchor member may extend only partially around an outer perimeter of the inner liner when the catheter is assembled. Proximal to the proximal end of the elongate body, a second portion of the push assembly, proximal to the first portion, may be positioned outside of the outer jacket and the inner liner.