Intra-aortic balloon pump

摘要

A retardation in the deflating motion of a balloon caused by a local collapse thereof is prevented. A tubular sleeve having a multiplicity of small apertures in the periphery therein is disposed for axial movement between the internal spaces of the balloon and a catheter. In use, the sleeve is inserted into the catheter to prevent a fluid channel from being blocked upon occurrence of a local collapse of the balloon. To facilitate positioning the sleeve, a projection is formed on an elongate stylet adjacent to its distal end to apply a braking action to the sleeve and secure it in place when the latter reaches a given position within the balloon.