Implantable heart-assist device

Abstract

An implantable heart-assist device including extra-aortic balloon pump (EAB pump) for use in cooperation with a fluid pump is disclosed. The extra-aortic balloon pump includes a rigid, generally cylindrical housing and a flexible, generally cylindrical diaphragm residing generally within a longitudinal passageway in the rigid housing and secured to the rigid housing so as to create a plurality of separate expansion chambers. A plurality of fluid communication ports are provided for passing fluid into and out of the respective expansion chambers. The rigid housing includes interior and exterior surfaces, proximal and distal ends, and a longitudinal passageway. The diaphragm has an inner surface which defines a longitudinal lumen within the longitudinal passageway. The longitudinal lumen has a longitudinal axis and the respective expansion chambers and corresponding fluid communication ports are oriented axisymmetrically in respect to the longitudinal axis. In preferred embodiments, the fluid pump is a fluid filled bladder within an innervated skeletal muscle pouch. The skeletal muscle pouch is preferably created surgically from a latissimus dorsi muscle flap which is preferably generated during a prior surgical procedure. The fluid filled bladder communicates with the EAB pump via fluid communication conduits and the fluid communication ports. Contraction of the skeletal muscle pouch is stimulated by an implantable pulse train generator which is synchronized with the beating of the active heart. Methods of assisting an active heart using the disclosed implantable heart assist device are also disclosed.