The progression of fenfluramine-associated valvular heart disease assessedby echocardiography

Background: An association between the dietary suppressants fenfluramine an d dexfenfluramine and valvular heart disease was first described in patient s from North Dakota and Minnesota in 1997. Limited data are available on th e natural history of this valvulopathy after discontinuation of drug therap y. Objective: To follow the progression of fenfluramine-associated valvular he art disease after discontinuation of therapy by using serial echocardiograp hy. Design: Retrospective cohort study. Setting: Regional medical center in Fargo, North Dakota. Patients: 50 patients with previous exposure to fenfluramines who had at le ast mild mitral regurgitation or aortic regurgitation after exposure to fen fluramines on serial echocardiography between December 1994 and February 19 99 (96% were female, mean body mass index was 36.6 kg/m(2), and mean durati on of drug exposure was 447 days). Measurements: serial echocardiograms were reviewed by two echocardiographer s who were blinded to the order of image acquisition. The severity of valvu lar regurgitation and presence or absence of valve leaflet restriction were assessed. Results: As described in the initial report, significant valvular disease o n initial postexposure echocardiography was common in this cohort; 38 patie nts (76%) had at least mild mitral regurgitation and 43 patients (86%) had at least mild aortic regurgitation. On serial echocardiograms obtained an a verage of 356 days apart, mitral regurgitation improved by at least one gra de in 17 patients (P = 0.001) and aortic regurgitation improved by at least one grade in 19 patients (P = 0.004). Nineteen and 22 patients, respective ly, experienced no change in severity of mitral and aortic regurgitation. T wo patients in each group experienced worsening of regurgitation by at leas t one grade. Results were similar for tricuspid (P = 0.002) and pulmonic (P = 0.012) regurgitation. Conclusion: On serial echocardiography, fenfluramine-associated valvular re gurgitation improved or remained stable in most patients after therapy ende d. Worsening of valvular regurgitation was uncommon. The potential for stab ilization or regression of valvular regurgitation should be taken into acco unt when counseling patients and considering the need for and timing of val ve surgery.