DILATED CARDIOMYOPATHY CAUSED BY ACUTE MYOCARDITIS IN PEDIATRIC-PATIENTS - EVOLUTION OF MYOCARDIAL DAMAGE IN A GROUP OF POTENTIAL HEART-TRANSPLANT CANDIDATES

Dilated cardiomyopathy, frequently caused by acute myocarditis, is a c ommon indication for heart transplantation in pediatric patients. The prognosis of children with acute myocarditis is not well known but is believed to be poor. We report the short-term follow-up in 20 pediatri c patients (mean age 22 +/- 19 months) with acute myocarditis diagnose d by endomyocardial biopsy. All patients were treated by immunosuppres sion (cyclosporine and steroids). Endomyocardial biopsy was repeated a fter 6 months in all patients and after 1 year in patients with persis tent acute myocarditis. To evaluate left ventricular function, two-dim ensional echocardiography was performed at the time of each endomyocar dial biopsy, and left ventricular end-diastolic volume index and eject ion fraction were calculated. After 6 months, endomyocardial biopsy sh owed persistence of acute myocarditis in 13 of 20 patients. After 1 ye ar, endomyocardial biopsy performed in 11 of 13 patients with persiste nt acute myocarditis showed ongoing acute myocarditis in 10 of 11 pati ents. On admission to the hospital, 16 of 20 patients had left ventric ular dilation (end-diastolic volume index 122 +/- 19 ml/m(2); normal v alues 63 +/- 17 ml/m(2)) and 20 of 20 had decreased contractility (eje ction fraction 34% +/- 11%; normal values 66.1% +/- 5.2%). After 6 mon ths, in all patients the end-diastolic volume index decreased to 73 +/ - 23 ml/m(2) (p < 0.001), and the ejection fraction increased to 56% /- 8% (p < 0.000001). After 1 year, end-diastolic volume index and eje ction fraction were stable (78 +/- 21 ml/m(2) and 55% +/- 9%, respecti vely). There was no need to consider transplantation. The short-term p rognosis of children affected by acute myocarditis and treated with im munosuppression is good. Left ventricular function improves within 6 m onths, although a complete recovery is rare. Histologic resolution of acute myocarditis is uncommon. Knowledge of the clinical course of pat ients with acute myocarditis is important in the ''transplant era'': p hysicians should be careful in advising transplantation for severe dil ated cardiomyopathy caused by acute myocarditis because even patients with major impairment of left ventricular function may improve and eve ntually recover. Longer follow-up is needed.