Diet drug-related cardiac valve disease: the Mayo Clinic echocardiographic laboratory experience

OBJECTIVE: To describe the prevalence of diet drug-related valvular disease among our referral population and the association of valvular disease with duration of exposure to fenfluramine and phentermine in combination and to dexfenfluramine alone. PATIENTS AND METHODS: In this retrospective review of clinical and echocardiographic data, charts of patients referred for treatment of toxic effects of diet drugs were reviewed, and telephone interviews were conducted. RESULTS: Between June and December 1997, 191 patients (164 women, 27 men; mean age, 47 years) were referred for possible diet drug-related valvular disease. Twenty-eight (28%) of the 99 asymptomatic patients and 40 (43%) of the 92 symptomatic patients had abnormal echocardiographic findings. Valvular lesions among the 68 patients with abnormal echocardiographic findings included mild (or greater) aortic regurgitation in 55 patients (81%), moderate (or greater) mitral regurgitation in 12 (18%), and moderate (or greater) tricuspid regurgitation in 7 (10%). The Food and Drug Administration case definition of diet drug-related valvulopathy was noted in 31 % of this referral population. Of patients with valvulopathy, mean duration of therapy with fenfluramine and phentermine in combination and dexfenfluramine alone was 9 months and 5 months, respectively. Duration of therapy was not associated with presence or absence of disease. Five patients had surgical intervention for severe valvulopathy: 3 had mitral valve repair, 1 had mitral valve replacement, and 1 had aortic valve replacement. Pulmonary hypertension (>40 mm Hg) was found in 24 patients (13%), and 17 (71 %) had pulmonary hypertension in association with valvulopathy. CONCLUSION: This study demonstrated a 31% (60/191) prevalence of valvulopathy in patients with a history of diet drug exposure who were referred for echocardiographic evaluation. The most common finding was mild aortic regurgitation. Twenty-eight percent of asymptomatic patients had abnormal echocardiographic findings. This study emphasizes the spectrum of diet drug-related cardiac disease and the potential for valvulopathy in asymptomatic patients.