Apparatuses, systems, and methods for crossing a tissue region may include a catheter and a tip section arranged therewith. The tip section may be configured to puncture the tissue region and create an opening therein, dilate the opening in the tissue region, and pass through the opening.

Methods and devices to facilitate positioning of a catheter into a vessel. Devices include axially concentric assemblies of a piercing needle and a dilator that guides an outer catheter into a vessel, such as a blood vessel. The assemblies described herein can include retraction mechanisms and/or lock mechanisms to control needle positioning during catheterization processes as well as improved valves that prevent leakage of fluid from the proximal end of the devices. The devices and method include the use of novel valves to prevent undesired leakage of fluids through the proximal end of the catheter.

An expandable introducer assembly includes a dilator subassembly extending from a proximal end to a distal end. The dilator subassembly includes a dilator having an insertion portion disposed adjacent the distal end, an expansion portion disposed adjacent the distal end, and a tapered transition portion disposed between the insertion and expansion portions. The dilator subassembly includes a distal sheath disposed in overlaying relationship with the insertion portion of the dilator. An introducer subassembly is disposed in coaxial relationship with the expansion portion of the dilator, and includes a valve disposed adjacent the proximal end and an introducer sheath extending from the valve in overlaying relationship with the expansion portion of the dilator. An expandable sheath subassembly is releasably interlocked with the dilator subassembly and includes an expandable sheath disposed in overlaying relationship with the tapered transition portion and in nested relationship between the insertion portion and the distal sheath.

A system for deploying a device to a distal location across a diseased vessel, comprising a sheath comprising an expandable distal portion comprising a porous wall defining a lumen there-through, the distal portion having a collapsed configuration, wherein the sheath has a first cross-sectional outer diameter and a first lumen inner diameter, and an expanded configuration, wherein the sheath has a second cross-sectional outer diameter and a second lumen inner diameter; wherein in the collapsed configuration, the sheath is configured to be advanced across at least a portion of the diseased vessel to a position adjacent the distal location and wherein said system comprises a removable expansion retention member configured to retain the expandable sheath in the collapsed configuration.

A method and apparatus are disclosed for puncturing tissue within a patient, comprising accessing a hepatic vein within the patient using an access device and inserting a flexible puncture device into the hepatic vein. The flexible puncture device advances from the hepatic vein to an inferior vena cava, and to the patient's heart. The next step is advancing a supporting catheter comprising a lumen over the flexible puncture device, whereby the flexible puncture device is positioned within the lumen and supported by the supporting catheter. The distal tip of the flexible puncture device and supporting catheter are positioned against a target tissue site and creating a puncture in said tissue, and the flexible puncture device is advanced through the puncture in the tissue.

A catheter assembly includes: a catheter having an inner cavity; and an inner needle retractably located in the inner cavity of the catheter. The inner needle includes: a barrel, a blade surface located distal of the barrel and being inclined with respect to a center axis of the inner needle, and an inner needle side locking surface located at least at a portion of an outer surface linking the barrel with the blade surface. An inner surface of the catheter includes a catheter side locking surface in contact with the inner needle side locking surface such that relative movement of the catheter in a proximal direction with respect to the inner needle is restricted.

This disclosure generally relates to devices, systems, or kits of color-coded dilation probes and corresponding sheath or jacket catheters that dilate tissue in an atraumatic manner to a desired depth and diameter for the insertion of a cannula. A jacketed catheter may be engaged to the probes and inserted into the dilated tissue to form a fluid-tight seal. An infusate is then introduced into the tissue through the catheter and held in the tissue for a desired period of time.

A valve bypass tool, and a biostimulator transport system having such a valve bypass tool, is described. The valve bypass tool includes an annular seal to seal against a protective sheath of the biostimulator transport system. The valve bypass tool is slidably mounted on the protective sheath and includes a bypass sheath to insert into an access introducer. The valve bypass tool can lock onto the access introducer by mating a locking tab of the valve bypass tool with a locking groove of the access introducer. The locking tab can have a decent that securely fastens the components to resist decoupling when the biostimulator transport system is advanced through the access introducer into a patient anatomy. Other embodiments are also described and claimed.

Embodiments herein include an insertion tool for inserting a medical device into another medical device, such as a hemostasis sealing valve, and related methods. In an embodiment, an insertion tool includes a guide sheath and a protection tube. The guide sheath can include a flared proximal end. The guide sheath can further include a central lumen. The guide sheath can further include a locking notch disposed on the inner surface between the proximal end and the distal end. The protection tube can include a flared proximal end. A portion of the protection tube can be situated within the central lumen of the guide sheath. The flared proximal end of the protection tube can be sized to fit within the locking notch and can have an outer diameter larger than portions of the inner surface immediately adjacent to the locking notch. Other embodiments are also included herein.

An introducer sheath, which is formed from a tubular member provided with a hollow portion through which an elongated body is freely insertable, and which includes a distal portion and a main body portion, wherein the inner diameter of the distal portion is formed to become gradually smaller toward the distal side, and on the inner surface of the distal portion, there is provided a hydrophobic coating having a friction coefficient lower than the friction coefficient of the tubular member.