Mitral regurgitation after anthracycline treatment for childhood malignancy

Objective-To investigate the new onset of mitral regurgitation in patients with otherwise normal echocardiograms after anthracycline treatment and to assess its relation to other selected indicators of myocardial damage. Design-Prospective echocardiographic and electrocardiographic study. Setting-Tertiary paediatric cardiac referral centre. Patients-305 patients, aged 2-33 years (median 14 years), treated with cumu lative anthracycline doses of between 150-450 mg/m(2) (median 180 mg/m(2)) for childhood malignancy. Main outcome measures--Colour flow Doppler detection of mitral regurgitatio n and its relation to changes in echocardiographic indices of left ventricu lar function (systolic and diastolic dimensions, fractional shortening) and to changes in the 12 lead EGG; and the prevalence of mitral regurgitation in the anthracycline treated patients in comparison with previously studied normal volunteers of similar age. Results-34 patients (11.6%) developed ultrasound detectable mitral regurgit ation, which was not apparent clinically, during or after anthracycline tre atment, compared with only 1.8% of a normal population of similar age (p < 0.0001). Nine of the 34 also developed non-specific T wave abnormalities. A ll 34 patients had normal systolic function at the time of initial detectio n of mitral regurgitation, but four later developed impaired left ventricul ar function (5, 11, 20, and 27 months after the first detection of mitral r egurgitation). Conclusions-Mitral regurgitation occurs much more often in patients treated with anthracyclines than in the normal population. Echocardiographic detec tion of new mitral regurgitation with or without ECG abnormalities may be a n early predictor of anthracycline cardiomyopathy.