[Appetite suppressants and heart valve disorders].

Serotoninergic appetite-suppressant drugs, fenfluramine and dexfenfluramine, were withdrawn from the market in September 1997 on account of two major cardiopulmonary complications: primary pulmonary hypertension and valvular regurgitation. The valvular heart diseases involve mainly left-sided valves, and contrary to physiological valvular regurgitations, they appear mostly on the aortic valve. Prolonged exposure (> 3 months) appears to confer a higher risk of cardiac valve involvement. Pathological features are similar to carcinoid or ergot alkaloid-induced valve diseases, and suggest a common pathophysiological mechanism which would also explain pulmonary hypertension by the toxic effect of high levels of circulating serotonin. After the first reports documenting a dramatically high prevalence of valvular side effects (up to 33% according to the Food and Drug Administration), recent studies reported a lower prevalence and severity. The long-term outcome and the real incidence are unknown and require further research and epidemiological data. A clinical survey of the patients exposed to serotoninergic appetite-suppressants is necessary, to be repeated 6 to 8 months later in the absence of an initial cardiac murmur. Doppler echocardiographic examination should be performed after prolonged exposure (> 3 months) or a high dosage of these drugs, in circumstances such as the presence of cardiovascular symptoms, a cardiac murmur, or an uncertain cardiac examination because of weight of patients.