Abstract 16092: Outcomes in Children with Familial Dilated Cardiomyopathy Compared to Children with Idiopathic Dilated Cardiomyopathy
Introduction: Prior research comparing survival of children with familial forms of dilated cardiomyopathy (FDCM) to children with idiopathic dilated cardiomyopathy (IDCM) has produced contradictory results.
Hypothesis: We hypothesized that patients with FDCM (2 or more family members with a positive cardiomyopathy history) would have better event-free survival (absence of death and heart transplantation) compared to patients with IDCM.
Methods: Using data from the NHLBI-funded Pediatric Cardiomyopathy Registry, we compared transplant-free survival and its predictors in 107 FDCM patients compared to 650 patients with IDCM. To account for differences in age and body size, echocardiographic parameters were expressed as Z-scores compared to a normal pediatric reference population. Median follow-up in event-free subjects was 3.9 and 2.1 years in the FDCM and IDCM cohorts, respectively.
Results: Median age at diagnosis was 3.9 years for FDCM and 1.0 year for IDCM (p=0.09). Compared to IDCM, FDCM was less likely to present with heart failure (HF; 55% vs. 80%, p< 0.001), had a less depressed ejection fraction (EF; 33% vs. 25% p= 0.001), lower left ventricular (LV) mass Z-score (2.1 vs. 2.6, p=0.017), lower LV end-systolic dimension Z-score (5.2 vs. 6.6, p< 0.001) and lower LV end-diastolic dimension Z-score (5.2 vs. 6.6, p=<0.001). Using Kaplan-Meier analyses survival was greater in the FDCM group (Logrank p= 0.001); freedom from death or transplant was also significantly better in FDCM compared to IDCM (78% vs. 60% at one year, logrank p= 0.009). Multivariable Cox regression modeling found that in patients with FDCM only end-diastolic LV dimension Z-score (HR= 1.08, p< 0.001) at diagnosis was independently associated with increased risk of death or heart transplantation
Conclusions: Transplant-free survival was significantly better in children with FDCM compared to IDCM. Better event-free survival for FDCM may be a result of early identification or improved clinical management in this at-risk population.
- © 2010 by American Heart Association, Inc.