Muscle and air powered LVAD

• US 5,397,349 A
• Filed: 07/30/1992
• Issued: 03/14/1995
• Est. Priority Date: 07/30/1992
• Status: Expired due to Term

• Current Assignee: University of Utah Research Foundation (State of Utah)
• Original Assignee: University of Utah Research Foundation (State of Utah)
• Inventors: Topaz, Stephen R., Bishop, N. Dan, Kolff, Willem J.
• Primary Examiner(s): Willse, David H.
• Application Number:
  US07/922,208
• Time in Patent Office: 957 Days
• Field of Search: 623/3, 623/25, 623/26, 600/16-18
• US Class Current: 623/3.3
• CPC Class Codes: A61M 60/161 mechanically acting upon the outside of the patient's blood vessel structure, e.g. compressive structures placed around a vessel
• CPC Class Codes: A61M 60/289 Devices for mechanical circulatory actuation assisting the residual heart function by means mechanically acting upon the patient's native heart or blood vessel structure, e.g. direct cardiac compression [DCC] devices
• CPC Class Codes: A61M 60/468 the force acting on the actuation means being hydraulic or pneumatic
• CPC Class Codes: A61M 60/515 Regulation using real-time patient data
• CPC Class Codes: A61M 60/857 Implantable blood tubes
• CPC Class Codes: A61M 60/882 Devices powered by the patient, e.g. skeletal muscle powered devices

Abstract

A method for providing ventricular assist to a patient with a weak or nonfunctional heart includes attaching an artificial ventricle to a patient and pumping said artificial ventricle with a muscle powered hydraulic pump. This method is enhanced by supplementing said artificial ventricle as needed with a pneumatic pumping system which is hermetically sealed from the hydraulic fluid. The hydraulic pumping power is amplified by driving a first pumping member of larger dimension against a second pumping member of smaller dimension to thereby supply increased force to overcome existing blood pressure.

Claims

1. A method for providing ventricular assist to a patient with a weak or nonfunctional heart, said method comprising the steps of:

a) attaching an artificial ventricle to the patient in a ventricular assist location;

b) pumping the artificial ventricle with a muscle powered pump which supplies a fluid as a driving force to pump blood from the artificial ventricle to the patient;

c) amplifying pumping pressure of the muscle powered pump by

(i) directing the driving force onto a first pumping member having a contacting side of larger dimension; and

(ii) directing said contacting side of said first pumping member against a contacting side of smaller dimension of a second pumping member without directing said first pumping member against any other pressure-resistant member to thereby transfer the driving force as increased pressure onto said second pumping member.

2. A method as in claim 1 wherein step (c) further comprises directing a hydraulic force against a portion of the first pumping member, said portion having a larger dimension than that of the entire second pumping member.

3. A method as in claim 1 wherein step (b) further comprises the following steps:

(d) wrapping a compressible hydraulic pumping chamber of the artificial ventricle with a muscle; and

(e) stimulating the muscle to expand and contract to thereby alternately compress and release the pumping chamber.

4. A method as in claim 3 wherein the first pumping member is an integral part of the hydraulic pumping chamber and the second pumping member is in integral part of a compressible blood pumping chamber of the artificial ventricle, step (c) further comprising transferring the driving force from the hydraulic pumping chamber onto a blood pumping chamber of the artificial ventricle.

5. A method for providing ventricular assist to a patient with a weak or nonfunctional heart, said method comprising the steps of:

a) attaching an artificial ventricle to the patient in a ventricular assist location;

b) pumping the artificial ventricle with a muscle powered pump which supplies a liquid actuated driving force to pump blood from the artificial ventricle to the patient; and

c) supplementing the artificial ventricle as needed with a pneumatic pumping system sealed from the liquid that operates with respect to the same ventricle;

wherein step (b) further comprises directing the driving force to one side of a pumping member having opposing sides, and wherein step (c) further comprises applying a pneumatic pumping force to a side of said pumping member opposite said one side.

6. A method for providing ventricular assist to a patient with a weak or nonfunctional heart, said method comprising the steps of:

a) attaching an artificial ventricle to the patient in a ventricular assist location;

b) pumping the artificial ventricle with a muscle powered pump which supplies a liquid actuated driving force to pump blood from the artificial ventricle to the patient; and

c) supplementing the artificial ventricle as needed with a pneumatic pumping system sealed from the liquid that operates with respect to the same ventricle;

wherein step (c) further comprises pumping the pneumatic pumping system in counterpulsation to the liquid actuated driving force.