Guidewire with reversible contact seal for releasable securement to

Abstract

An exchangeable catheter-guidewire system is disclosed in which the guidewire can be manipulated to seize and to release itself from the catheter body while both are in place in a vasculature or other body vessel. For balloon dilatation catheters, this arrangement permits one to transmit the fluid used for perfusion and/or balloon inflation through the same lumen through which the guidewire passes. Balloon catheters which utilize the invention have the capacity to secure the position of the guidewire relative to the catheter body, as well as to seal the lumen and balloon to retain fluid under pressure, both by remote control from the proximal end of the catheter. The seizure and sealing are achieved by a deformable section on the guidewire, which expands upon deformation to seize a tubular section of the catheter body. Two examples of deformation are given, the first occurring with a deformable section which is sufficiently flexible to gather into folds upon longitudinal compression, the folds being bulky enough to expand outward, and the second occurring with a deformable section which is inflatable. In either case, the guidewire in preferred embodiments is constructed as a hollow tube with a central rod which in both cases serves to enhance the longitudinal strength of the guidewire and, in the first case, also serves as a means of compressing and re-extending the deformable section of the tube. Either mechanism permits the construction of an exchangeable catheter system with the crossing profile of non-exchangeable systems.