Clinical and echographic characteristics of patients exposed to fenfluramin or its derivatives: Results of a prospective, single-centre, observational study.

BACKGROUND

Fenfluramine and its derivatives have been associated with significant risk of developing valvular heart disease but its exact prevalence and severity are still debated.

AIM

To evaluate the clinical and echocardiographic characteristics of patients hospitalized in a cardiology centre and who had past exposure to these drugs.

METHODS

Between July 2011 and February 2012, patients admitted to the hospitalization and intensive care units at the University Centre of Montpellier, France were questioned about past exposure to fenfluramine or its derivatives. In patients who reported exposure, a questionnaire assessing prescribing patterns and medical history was proposed and echocardiography performed. All of the usual echocardiographic variables were analysed. We applied criteria from a French multicentre registry for diagnosis of drug-induced valvulopathy: leaflets and subvalvular apparatus thickening and retraction, leaflets loss of coaptation, no calcification, and no stenosis.

RESULTS

Ninety-five patients exposed to these drugs were included. The majority were female (n=62, 65.3%), 53.2% (n=50) had diabetes and 90.5% (n=86) were exposed to benfluorex. Mean treatment duration was 52.3months (95% confidence interval [CI] 39.0-65.6). Valvular regurgitations were observed in 64.0% of patients (n=57) while 19.8% (n=17) had pulmonary hypertension. Highly probable fenfluramine-induced regurgitations were present in 18.6% (n=16) of patients, possibly fenfluramine-induced regurgitations in 38.2% (n=34) of patients, and unlikely fenfluramine-induced regurgitations in 25.8% (n=23) of patients. Highly probable fenfluramine-induced regurgitations were mild to moderate in severity in all except three patients.

CONCLUSION

Considering the frequency of probable or possible fenfluramine-induced regurgitations and in the absence of definite knowledge about the evolution of drug-induced valvular disease, systematic questioning about fenfluramine use may be advisable in hospitalized cardiac patients.