Skeletal muscle mass and exercise performance in stable, ambulatory
patients with heart failure.
Lang, Chim C., Don B. Chomsky, Glenn Rayos, T. K. Yeoh, John R.
Wilson.
Cardiology Division of the Vanderbilt University Medical
Center.
APStracts 3:0444A, 1996.
The purpose of this study was to determine if skeletal muscle atrophy
limits the maximal exercise capacity of stable, ambulatory patients
with heart failure. Body composition and maximal exercise capacity
were measured in 100 stable, ambulatory patients with heart failure.
Body composition was assessed using dual energy x-ray absorption.
Peak exercise oxygen consumption (VO2) and the anaerobic threshold
were measured using a Naughton treadmill protocol and a Medical
Graphics CardioO2 System. Peak exercise VO2 averaged 13.4+3.3
ml/min/kg or 43+12% of normal. Lean body mass averaged 52.9+10.5 kg
and leg lean mass 16.5+3.6 kg. Leg lean mass correlated linearly with
peak exercise VO2 (r=.68, p<.01), suggesting that exercise
performance is influenced by skeletal muscle mass. However, lean body
mass was comparable to levels noted in 1584 normal control subjects,
suggesting no decrease in muscle mass. Leg muscle mass was comparable
to levels noted in 34 normal control subjects, further supporting
this conclusion. These findings suggest that exercise intolerance in
stable, ambulatory patients with heart failure is not due to skeletal
muscle atrophy.
Received 22 May 1996; accepted in final form 17 September 1996.
APS Manuscript Number A484-6.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 5 November 1996