Abstract: A catheter system having a changeable distal member. The catheter system includes a proximal member, including a shaft having a proximal end, a distal end and a lumen extending therethrough. A distal member is included having a distal portion which may be passed through the lumen of the proximal member and releasably sealed to the proximal member at a desired location during a catheter procedure. The distal member may further include a push member operably coupled to the distal portion. The distal member may include a fluid-tight releasable seal for releasably sealing the distal member to the proximal member.

Abstract: The present invention is a device and method for controlling longitudinal movement of a tube relative to a shaft slidably disposed within the tube, especially in the catheterization of a patient. An operative segment on the shaft cooperates with an ancillary tool to create a coupling force field between the shaft and the tool. The tube can then be moved over the shaft while the coupling force field operates through the tube to restrict the movement of the shaft. In preferred embodiment, the shaft is a guide wire and the tube is a catheter with a lumen for slidably receiving the guide wire, while the coupling force field is created magnetically. In one embodiment, the operative segment is borne on a short guide wire extension which is selectively securable to a standard guide wire. In another embodiment a pair of electrical coils are placed around the magnetically operative segment to couple therewith and provide signals indicative of the movement and position of the guide wire.

Abstract: An improved balloon catheter for angioplasty and the like for measuring the inflation of a balloon after insertion into the body. A pair of electrodes are mounted in spaced relation within the balloon interior wall such that as the internal area within the balloon is varied by inflation of the balloon with an electrically conductive fluid, the electrodes monitor the changing electrical resistance between the electrodes. The electrodes are connected through the catheter to an external electrical measurement circuit for measuring the change in resistance and thus determining the amount of balloon inflation.