Myocardial L-carnitine deficiency in a family of dogs with dilated cardiomyopathy.

Dilated cardiomyopathy in a family of dogs was found to be associated with decreased myocardial L-carnitine concentrations, when compared with those in control dogs. In 2 affected dogs, treatment with high doses of L-carnitine was associated with increased myocardial L-carnitine concentration and greatly improved health and myocardial function. Withdrawal of L-carnitine supplementation from these dogs resulted in development of myocardial dysfunction and clinical signs of dilated cardiomyopathy.