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Updated: Jul 12, 2026
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Use of Two Intracorporeal Ventricular Assist Devices As a Total Artificial Heart
Published on: May 11, 2018
A ventricular assist device powered by conditioned skeletal muscle.
R L Whalen1, C L Richards, G W Lim
1Whalen Biomedical Laboratories, Somerville, Massachusetts 02143, USA. rlwhalen@ix.netcom.com
The Annals of Thoracic Surgery
|September 4, 1999
Summary
Researchers are testing a new skeletal muscle-powered ventricular assist device (VAD). Muscle fiber changes occurred, but device performance varied, suggesting perfusion is key for VAD function.
Area of Science:
- Biomedical Engineering
- Surgical Innovation
- Regenerative Medicine
Background:
- Developing a novel ventricular assist device (VAD) powered by conditioned skeletal muscle.
- Investigating the feasibility of using skeletal muscle for VAD applications.
Purpose of the Study:
- Evaluate VAD hardware performance and optimize a muscle training regimen.
- Assess the long-term viability and function of skeletal muscle grafts for VADs.
Main Methods:
- Utilized 8 calves for a 4-month study involving the right latissimus dorsi muscle.
- Employed identical VAD hardware, surgical techniques, and training protocols across all subjects.
Main Results:
- Observed significant conversion of type II (fast-twitch) to type I (slow-twitch) muscle fibers.
- Demonstrated wide variability in device stroke volumes (17-90 cc) despite consistent methods.
- Found no strong correlation between muscle fiber type conversion and VAD performance.
Conclusions:
- Speculated that tissue perfusion, not just muscle work, is critical for VAD function at lower pressures.
- Proposed investigating thermally induced angiogenesis to enhance blood flow and improve VAD performance.
- Highlighted the need for further research into optimizing skeletal muscle conditioning for VADs.
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