Abstract 3356: Outcome and Risk Stratification for Children With Left Ventricular Noncompaction: Findings From the Pediatric Cardiomyopathy Registry
Background: Left ventricular noncompaction (LVNC) is a distinct morphologic form of cardiomyopathy characterized by hypertrabeculated or spongy endo-myocardium in the apical wall of the left ventricle. LVNC may occur in isolation, or in association with other primary cardiomyopathies or structural cardiac anomalies. Characterization of LVNC in children remains limited.
Methods: We analyzed Pediatric Cardiomyopathy Registry data from 3219 children with cardiomyopathy diagnosed between 1990 and 2008. Patients (pts) with LVNC with/without other accompanying CM [dilated (DCM); hypertrophic (HCM); restrictive (RCM)] were identified by echocardiography. We estimated death, cardiac transplant, and death/transplant rates and examined risk factors for death/transplant.
Results: LVNC was present in 158 pts (4.9%). LVNC was more often diagnosed in infancy (<1 yr) compared to all other pts (52% vs. 37%, p<.001). Death rates for LVNC pts at 1 and 5 yrs post-diagnosis were 16% and 18%; this 5-yr rate was between that of pure HCM and pure DCM pts (15%, 22%) and lower than mortality for pts with RCM/Other CM (26%). Death/transplant was observed in 40 LVNC pts, 22% at 1 yr and 32% at 5 yr post-diagnosis. In LVNC pts, lower fractional shortening z-score (FSz) and ejection fraction and higher LV mass z-score were univariate risk factors for death/transplant; but only FSz was an independent risk factor. Lower (below median of −5) FSz was strongly predictive of death/transplant (p<.001), regardless of presence or type of cardiomyopathy. In 112 pts with FSz available, 23 of 24 events occurred when FSz was <−5 (hazard ratio for death/transplant=26.5, 95% confidence interval 3.6 to 197). This risk stratification revealed 1-and 5-yr death/transplant rates of 34% and 55% for LVNC pts with FSz <−5 and 2% overall for LVNC pts with FSz ≥−5.
Conclusions: LVNC is a clinically heterogeneous cardiomyopathy that may present in isolation or in the setting of DCM, HCM, or RCM. LVNC is typically diagnosed in infancy as compared to other pediatric cardiomyopathies. LVNC with preserved systolic ventricular function has excellent outcome at 1 and 5 years with rare need for transplant.