CATHETER TIP DESIGNS AND METHODS FOR IMPROVED STENT CROSSING

摘要

A balloon catheter having a first balloon member and a second distal expandable member. The increased distal profile of the catheter with inflation of the second distal expandable member can deflect the distal-most end away from stent walls and edges. Another catheter has a distal region including longitudinal slits and a pre-stressed body configured to expand upon exposure to warm body fluids. Another catheter has a distal region including a first, inner tube disposed about a second, innermost tube. The inner and innermost tubes are secured at the distal-most end. The distal region includes longitudinal slits through the inner tube, thereby defining flaps between the slits. The innermost tube can be retracted relative to the inner tube disposed about the innermost tube, thereby causing the longitudinal flaps to expand outward, thereby increasing the maximum radial extent of the distal region. In yet another embodiment, a balloon catheter having a first guide wire tube is provided. A second guide wire tube is also provided, adapted to be received within the larger, first guide wire tube.