Cardiomyoplasty: degeneration of the assisting skeletal muscle. Ianuzzo, C. David, Sigrid E. Ianuzzo, Nancyleigh Carson, Margaret Feild, Marius Locke, Jiang Gu, William A. Anderson, Richard E. Klabunde. Deborah Research Institute and Deborah Heart and Lung Center, 20 Pine Mill Road, Browns Mills, New Jersey 08015-1799
APStracts 2:0551A, 1995.
This study determined effects of surgical dissection and chronic stimulation on degeneration of the latissimus dorsi muscle (LDM), the muscle used for contractile assistance in cardiomyoplasty. LDM from 10 goats were allocated into four groups: N-LDM (normal), D-LDM (dissected muscle and collateral vessels ligated, muscle remained in original anatomic location), S-LDM (electrically stimulate for 62-75 days), and DS-LDM (dissected and stimulated). S-LDM had nearly a complete transformation to type-I fibers throughout the length of the muscle. Both groups of dissected muscles (D- and DS-LDM) showed lesser transformation and significant damage. Type-I myosin heavy chain and citrate synthase activity were less in the distal compared to the proximal LDM. Morphology of the N- and S-LDM were normal, whereas, dramatic morphological abnormalities were observed in the D- and DS-LDM, including lipid containing ghost-like fibers, atrophied and hypertrophied fibers within the same fascicle. In conclusion, muscle degeneration associated with the cardiomyoplasty procedure was caused by surgical dissection, which was exacerbated by chronic stimulation but was not caused by stimulation alone.

Received 22 June 1995; accepted in final form 28 November 1995.
APS Manuscript Number A669-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 23 December 95