The present disclosure provides a catheter system and methods for use that includes (a) a first catheter having a first end and a second end, where the first catheter has a first diameter, (b) a second catheter having a first end and a second end, where the second catheter has a second diameter that is less than the first diameter of the first catheter, and where the second catheter is positioned at least partially within a lumen of the first catheter and is moveable relative to the first catheter, and (c) a wire having a first end and a second end, where the first end of the wire is coupled to the second catheter.

Provided is a dilator capable of increasing the diameter of a hole formed on the wall of a digestive tract and the like while ensuring distal-end flexibility and maintaining pushability and torquability even when a shaft is longer and curved. A dilator includes a hollow shaft having an outer diameter that is smaller at a distal end than at a proximal end, and a grip portion connected to the proximal end of the shaft. A spirally-arranged protruding portion protruding outwardly is provided on an outer peripheral surface of the shaft. The spirally-arranged protruding portion has gaps between adjacent portions along a longitudinal axis of the shaft.

Rapidly insertable central catheters (“RICCs”) including catheter assemblies and methods thereof are disclosed. For example, a RICC assembly includes a RICC and an introducer. The RICC includes a catheter tube, a catheter hub, and one or more extension legs coupled in the foregoing order. The catheter tube includes a side aperture that opens into an introducing lumen that extends from at least the side aperture to a distal end of the RICC. The introducer includes a retractable-needle device, a syringe, and a coupling hub that couples the retractable-needle device and the syringe together proximal of the side aperture in a ready-to-deploy state of the RICC assembly. The retractable-needle device includes an introducer needle. A needle tip in a distal-end portion of a shaft of the introducer needle extends beyond the distal end of the RICC when the RICC assembly is in the ready-to-deploy state of the RICC assembly.

A releasable coupling mechanism for coupling a delivery catheter and a dilator. The delivery catheter comprising a first mating member at the proximal end and the dilator comprising a second mating member at the proximal end. The proximal end of the first mating member comprises a first coupling means for releasably receiving a second coupling means which is positioned at a distal end of the second mating member. The first mating member further comprising a coupling member the coupling member comprising a pair of engagement members positioned on opposing sides of the coupling member and configured to releasably engage the second coupling means. The first mating member further comprising at least one indicia perpendicular from the pair of engagement members. The indicia indicate an orientation of the first mating member such that the second mating member disengages from the coupling member by simultaneously deflecting the pair of engagement members.

Intravascular access is achieved by introducing a catheter having a guide element recess placed to receive the contoured distal end of a guide element. The guide element may be advanced along an outer surface of an access needle to form a loop beyond the distal end of the needle. The deployed guide element may form a partial or complete loop once beyond the distal end of the needle. After the catheter has been properly positioned, the access needle and guide element may be removed by automatic withdrawal leaving the catheter in place within a blood vessel and available for use.

An inserter for guiding a device through a hemostasis valve. The inserter comprises an elongate tubular body, a concave landing zone, and an axially extending slit. The elongate body tubular body of the inserter partially defines a central lumen. A method a of passing a device through a valve comprises the steps of providing an inserter having a tubular body with a split sidewall, advancing the tubular body through a valve, advancing a device through the tubular body and beyond the valve and retracting the tubular body so that the device escapes laterally from the tubular body through the split sidewall, leaving the device in place across the valve.

A catheter system for atraumatic placement along a guidewire includes: a catheter including a cylindrical catheter body that defines a longitudinally extending interior lumen; and a guide device. The guide device includes: a conduit member for insertion into the interior lumen of the catheter body; a leading structure connected to a forward end of the conduit member, the leading structure including a cone and a sleeve extending forward from the cone; and an inner guide hole extending longitudinally through the leading structure and conduit member. In use, the guide device and catheter body are coaxially arranged, the cone is forward of the catheter, and the sleeve extends forward from the cone. The cone includes a shoulder, and a tapered exterior that increases diametrically from the sleeve to the shoulder. The shoulder abuts a distal end of the catheter to register insertion of the guide device in the catheter.

Provided is a dilator capable of increasing the diameter of a hole formed on the wall of a digestive tract and the like while ensuring distal-end flexibility and maintaining pushability and torquability even when a shaft is longer and curved. A dilator includes a hollow shaft having an outer diameter that is smaller at a distal end than at a proximal end, and a grip portion connected to the proximal end of the shaft. A spirally-arranged protruding portion protruding outwardly is provided on an outer peripheral surface of the shaft. The spirally-arranged protruding portion has gaps between adjacent portions along a longitudinal axis of the shaft.

Valve assemblies having improved ability to selectively control flow of fluids through the catheter and prevent leakage of fluids from the proximal end of a catheter that is positioned within a patient. Such improved catheter valve assemblies also prevent leakage of fluids after repeated insertion and removal of medical instruments through the valve.

Provided is a dilator capable of increasing the diameter of a hole formed on the wall of a digestive tract and the like while ensuring distal-end flexibility and maintaining pushability and torquability even when a shaft is longer and curved. A dilator includes a hollow shaft having an outer diameter that is smaller at a distal end than at a proximal end, and a grip portion connected to the proximal end of the shaft. A spirally-arranged protruding portion protruding outwardly is provided on an outer peripheral surface of the shaft. The spirally-arranged protruding portion has gaps between adjacent portions along a longitudinal axis of the shaft.