Idiopathic Dilated Cardiomyopathy in Children: Natural History and Predictors of Prognosis

Abstract

Dilated cardiomyopathy is the most common type of heart muscle disease in children with idiopathic etiology in the majority of cases. Idiopathic dilated cardiomyopathy (IDCM) is a severe illness which carries a high mortality rate in the pediatric population. In order to characterize IDCM evolution and identify prognostic predictors in our pediatric cardiology center in the western province of Saudi Arabia, 55 patients with IDCM were evaluated clinically and by echocardiography. They were followed for a minimum of one year and a maximum of four and a half years. Patients less than two years of age represented 69% of the cohort. Gender distribution revealed 65.5% female and 35.5% male. Outcomes were divided into four groups: 25 patients (45.5%) improved (Group I), 17 patients (31%) had a stationary course (Group II), 13 patients (23.6%) deteriorated (Group III), and eventually 11 patients (from Group III) died. Survival rate was 80% with a mean follow-up period of 36.2 ± 22.1 months. The older the age at presentation, the worse the prognosis, with P value= 0.029. In this study, we found a significant correlation of prognosis with end diastolic volume (EDV) (P=0.05) as well as stroke volume (SV) (P=0.04) on presentation. However, fractional shortening of ejection fraction on presentation could not be correlated statistically to the prognosis. Also results suggested that higher z-score of intraventricular septum & Left ventricular posterior wall dimensions in diastole significantly correlated to favorable outcomes and higher z-score of Left ventricular end diastolic dimension (LVEDD) was significantly related to unfavorable outcome. We concluded that further multi-center studies are necessary to verify predictors of outcome in IDCM patients. Identification of markers affecting early myocardial function is essential to achieving improvements in treatments and consequently outcomes in this pediatric population.

Keywords: dilated cardiomyopathy, children, natural history, predictors of prognosis, echocardiography