Severity of mitral regurgitation predicts risk of death or cardiac transplantation in children with idiopathic dilated cardiomyopathy.

Clinical outcomes among children with idiopathic dilated cardiomyopathy (IDC) are diverse, which makes the decision as to when a patient should be listed for a cardiac transplantation challenging. This study aimed to determine echocardiographic and clinical variables that can help clinicians identify those at highest risk for death or cardiac transplantation. The study was a single-center, retrospective chart review of children with IDC. Patients younger than 18 years with a diagnosis of IDC, as defined by a left ventricular end-diastolic dimension (LVEDD) z-score higher than 2, and fractional shortening of less than 28 % on the initial echocardiogram, were included in the study. Echocardiographic parameters including mitral regurgitation (MR) grade and certain clinical parameters at the time of presentation were assessed. A follow-up echocardiogram was similarly studied. The study included 49 children with IDC. Those who died or underwent cardiac transplantation were grouped as "nonsurvivors" (n = 26). The remaining children who either completely recovered or experienced chronic dilated cardiomyopathy were grouped as "survivors" (n = 23). The median age overall was 1.25 years (range 0.1-17 years). The follow-up echocardiograms of the survivors showed significant improvement in left ventricle size, systolic function, left atrial volume, and MR grade, whereas these parameters did not change in the nonsurvivor group. The use of inotropic medications at initial presentation was an independent predictor of death or cardiac transplantation (p < 0.05). The presence of moderate to severe MR at diagnosis also was predictive of a worse outcome.