Sheath for an adjustable length balloon

摘要

A dilatation catheter assembly which has a dilatation catheter with a sheath mounted on the catheter shaft having an inner lumen extending in the distal portion of the sheath which is configured to slidably receive at least a portion of the dilatation balloon on the distal end of the catheter. The position of the sheath is fixed with respect to the catheter, e.g. a friction fit or bonded in some manner, before the assembly is inserted into the patient's vasculature with the distal portion of the sheath covering a portion of the balloon but leaving a portion of the balloon uncovered with a length equal to the stenotic region to be dilated so that the entire stenosis can be dilated at the same time. The distal portion of the sheath is preferably formed of a flexible polymeric tube with inelastic reinforcement to prevent substantial expansion thereof when the balloon is inflated.