Effects of ACE inhibition and beta-blockade on skeletal muscle fiber types in dogs with moderate heart failure

Early use of enalapril or metoprolol helps maintain the proportion of fatigue-resistant type I skeletal muscle fiber in dogs having had moderate heart failure. Angiotensin-converting enzyme inhibitors decrease the congestive heart failure incidence in patients with LV dysfunction. The compounds also prevent progressive LV dysfunction and dilation. Beta-blockers improve LV ejection fraction, and decrease chamber dimensions in patients with dilated cardiomyopathy.