TRANSIENT REDUCTION OF HUMAN LEFT-VENTRICULAR MASS IN CARNITINE DEPLETION INDUCED BY ANTIBIOTICS CONTAINING PIVALIC ACID

Objective-To study the effect of induced carnitine depletion on myocar dial structure and function. Subjects and Design-7 healthy adult volun teers given 1200 mg pivmecillinam per day for 7-8 weeks were studied b y echocardiography before and after 7-8 weeks of treatment and a 15 mo nths follow up after the treatment period. Setting-Teaching hospital. Main outcome measures-Carnitine concentration in serum, urine, and mus cle and echocardiographic measurements. Results-After 7-8 weeks of tre atment the median free serum carnitine concentration was reduced to 7% and the median total muscle carnitine concentration to 46% of the pre treatment levels. The median diastolic interventricular septum thickne ss decreased by 14% (mean 26%, P = 0.028) and the median left ventricu lar mass by 10% (mean 20%, P = 0.018). Fifteen months dimensions had i ncreased completely returned to pretreatment values. Conclusions-Exten ded treatment with pivalic acid containing antibiotics causes carnitin e depletion which may lead to changes in cardiac structure.