Etiology and prognosis of 183 cases with primary dilated cardiomyopathy

Abstract

Objective To explore the etiology, clinical features and outcomes predictors of pediatric dilated cardiomyopathy(DCM). Methods The clinical findings and follow-up data of 183 pediatric DCM patients who were diagnosed during Jan.2008 to Dec.2012 were analyzed. Results In the 183 patients, the cause of 24 cases(13.1%)was known; but the etiology of 132 follow-up cases remain unknown, 85 were male(64.0%) and 47 were female(36.0%); 33 cases(25.0%) recovered, 62 cases(47.0%)died, and 37 cases(28.0%) remained the same.The median age of onset was 8 months(ranged from 1 day to 15 years). The onset age of the patients who had recovered was younger than the dead(P<0.001) and the unchanged patients(P=0.008). For the dead cases, the heart function on diagnosis was worse than the cured(P<0.001) and the unchanged patients(P=0.015); the left ventricular ejection fraction(LVEF) and the left ventricular fractional shortening(LVFS) detected by ultrasonic cardiogram were significantly lower than those of the cured(P=0.006, 0.009) and the unchanged (P=0.013, 0.006); the cases with mode-rate and serious mitral regurgitation(MR) were also more than the other groups(P=0.003, 0.004); The cases in the unchanged group were less than those of the cured group and the dead group whose serum concentration of cardiac troponin I was≥0.10 μg/L(P=0.002, 0.004). For the 159 cases with the unknown cause, 1-year survival rate was 67% and 5-year survival rate was 46%.By multivariable analysis, LVFS[hazard ratios(HR)0.890, 95% confidence interval (CI)0.836-0.948, P<0.001], moderate and serious MR[HR 3.580, 95%CI 2.030-6.315, P<0.001], malignant ventricular arrhythmia[HR 2.062, 95%CI 1.009-4.213, P=0.047], abnormal Q wave[HR 4.044, 95%CI 1.851-8.832, P<0.001]were associated with increased risk of death. Conclusions Twenty-five percent pediatric idiopathic DCM patients with the unknown cause recovered after proper treatment, and nearly 50.0% patients died; 1-year survival rate was 67.0% and 5-year survival rate was 46.0%.Three months after onset, the patients whose left ventricular function improved obviously had a better outcome.Risk factors for death include LVFS, moderate and serious MR, malignant ventricular arrhythmia, abnormal Q wave. Key words: Dilated cardiomyopathy; Etiology; Outcomes; Child