US 5,558,617 A · Cardiac compression band-stay-pad assembly and method of replacing the same

Abstract

A ventricular assist device for a heart includes a compression band-stay-pad assembly for encircling substantially the heart perimeter and comprising an elongated band member or chain disposed in a sealed protective structure filled with a lubricating medium. The band member may be fixed at one end and wound upon, or unwound from, a rotatable spool by a drive motor through a speed reducer. Force-transmitting support or stay assemblies are disposed in the protective structure between the band member and a resilient pad assembly for encircling the heart and promoting heart tissue ingrowth therein. The force-transmitting stay assemblies are biased circumferentially, and thus radially outward, by compression return springs disposed therebetween. The resilient pad assembly includes a corrugated surface provided with vertical coil springs, which help prevent damage to heart tissue and facilitate return of the pad assembly to an initial condition, embedded defibrillator electrodes and relatively soft portions to prevent damage to coronary arteries. The device may be constructed so that it can be surgically removed, except for a sealing film and an ingrown pad assembly, which remain in situ on the heart. A net structure suspended below the device supports the apical portion of the heart. In certain embodiments, power or motor devices are provided between respective ones of the force-transmitting stay assemblies to contract and expand the device. The circumferential length of the assembly may be adjustable and/or may comprise two band members movable in opposite directions.

Claims19

Dependent claims

A resilient pad assembly adapted for use in a ventricular assist device during direct mechanical assist to a heart, comprising:

a. a resilient elongated band member for encircling and disposal on at least a portion of the heart, said band member receiving a mechanical compression force from said ventricular assist device and transmitting said mechanical compression force to the heart;
b. a resilient sheath assembly having an inner interface assembly and an outer membrane, said band member being encased in said sheath assembly between said inner interface assembly and said outer membrane, at least a portion of said inner interface assembly adjustably persisting in intimate contact with the heart;
and
c. a plurality of spaced-apart stay members movable on and mounted on said band member for circumferentially distributing at least a portion of said mechanical compression force to the heart.

1 more element

A resilient pad assembly adapted for use in a ventricular assist device during direct mechanical assist to a heart, comprising:

a. a resilient sheath assembly having an inner interface assembly and an outer membrane, at least a portion of said inner interface assembly having a porous pad assembly for facilitating tissue ingrowth thereto thereby forming a pad assembly-heart connection;
b. a resilient chain for encircling and disposal on at least a portion of the heart, said chain receiving a mechanical compression force from said ventricular assist device and transmitting said mechanical compression force to the heart, said chain being encased between said inner interface assembly and said outer membrane;
c. a plurality of spaced-apart stay members and a plurality of stay links, each of said stay members being pivotably mounted on at least one of said stay links, each of said stay links being movable on and mounted on said chain, said stay members circumferentially distributing at least a portion of said mechanical compression force to the heart;
d. said resilient pad assembly for encircling and contacting substantially the entire perimeter of a surface portion of the heart when the heart is in a diastolic phase, a surface of said pad assembly for contacting said surface portion of the heart being a heart-contacting surface;
e. said resilient pad assembly being formed of a resilient material such that said resilient pad assembly is capable of being cyclically shortened and lengthened in the perimeter direction during systolic and diastolic phases of the heart, respectively;
and
f. said resilient material receiving and transmitting said mechanical compression force to the surface portion of the heart.

4 more elements

Dependencies are inferred from the claim text.

Cardiac compression band-stay-pad assembly and method of replacing the same

Life of this patent

Cardiac compression band-stay-pad assembly and method of replacing the same

Life of this patent

Abstract

Claims19