Left ventricular function during strength testing and resistance exercise in patients with left ventricular dysfunction.
OBJECTIVE
Deterioration in left ventricular function is a more sensitive marker of myocardial ischemia during exercise than ST segment depression. The current study was designed to evaluate left ventricular function during one-repetition-maximum (1-RM) strength testing and resistance exercise in cardiac patients with moderate left ventricular dysfunction.


METHODS
Using echocardiographic methods, left ventricular function was evaluated in 15 patients with left ventricular dysfunction (age, 65 +/- 6.5 years; ejection fraction, 42.1 +/- 5.8). Measurements were performed during 1-RM testing and resistance exercise (20%, 40%, and 60% of 1-RM using 10 to 15 repetitions) on the one-arm biceps curl (BIC) and bilateral knee extension exercises and compared with measurements of left ventricular function during the symptom-limited graded exercise test (SL-GXT).


RESULTS
During the knee extension exercise, there was a slight but significant reduction (P< or =.05) in ejection fraction values at the end of 60% 1-RM, as compared with rest and previous workloads. Significant increases in systolic blood pressure and left ventricular end-systolic volume ratio values (P< or =.05) from rest to exercise were observed across test modes and for all workloads. The prevalence of new wall motion abnormalities during knee extension and BIC 1-RM strength testing was comparable with that observed during SL-GXT. The greatest increase in new wall motion abnormalities was seen during 60% 1-RM of knee extension exercise, as compared with prior workloads, BIC exercises, and SL-GXT.


CONCLUSIONS
Despite an increase in occurrence of ischemic changes during the highest resistance exercise workloads and with larger muscle mass, the findings are small in magnitude and do not suggest reduced cardiac performance.
Werber-Zion
Galila
G
York College of The City University of New York, Jamaica 11451, USA. werber@york.cuny.edu
Goldhammer
Ehud
E
Shaar
Anat
A
Pollock
Michael L
ML
D000368:Aged; D003324:Coronary Artery Disease / Q000150:complications / Q000534:rehabilitation*; D004452:Echocardiography; D005080:Exercise Test; D017079:Exercise Tolerance; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000502:physiology*; D015203:Reproducibility of Results; D018487:Ventricular Dysfunction, Left / Q000150:complications / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014891:Weight Lifting / Q000502:physiology*