Abstract 17300: Utility of Late Gadolinium Enhancement and Left Ventricular Mass as Assessed by Cardiac Magnetic Resonance in Children With Hypertrophic Cardiomyopathy
Background: Cardiac magnetic resonance (CMR) has emerged as a tool in risk stratification of adult patients with hypertrophic cardiomyopathy (HCM). The incidence of late gadolinium enhancement (LGE) and the prognostic value of CMR in children with HCM are unknown.
Objectives: To determine the association between 1) extent of LGE and 2) LV mass index (LVMI) as evaluated by CMR with known risk factors for poor outcomes in children with HCM such as non-sustained ventricular tachycardia (NSVT) and worsened diastolic function (mitral E/e’ ratio).
Methods: We retrospectively reviewed CMR and echocardiogram studies performed as part of routine clinical care. LVMI was calculated and a blinded observer reviewed studies for the number of LV segments with regional hypertrophy, LGE, and resting perfusion defects. We compared these CMR measures to known risk factors for poor outcomes.
Results: CMR was performed in 41 patients (age 13.1 ± 4.9 years, 76% male) with HCM. The average follow up was 5.37 ± 4.4 years. Evaluation for LGE was performed in 34 (83%) patients and 18 (53%) were positive. NSVT was present in 7 patients of which 5 had LGE (p=0.25). The average LVMI in patients with NSVT was 27.7 ± 14.7 g/m2 compared to 14.0 ± 6.3 g/m2 in those without NSVT (p=0.05). The relationship between extent of LGE and presence of NSVT approached significance; the median number of myocardial segments with LGE was 5 (range 0-8) in patients with NSVT and 1 (range 0-9) in patients without NSVT (p=0.07). There were no differences between patients with and without NSVT in the number of LV segments with regional hypertrophy or resting perfusion abnormality. The average mitral annular E/e’ ratio in patients with LGE was 10.4±3.3 compared to 8.3±2.8 in those without LGE (p=0.05). There was a positive correlation between mitral annular E/e’ ratio and LVMI (Rp=0.55, p<0.01). One patient in our cohort underwent heart transplant, one patient experienced aborted sudden death, and no patient died.
Conclusions: Increased LVMI was associated with NSVT and worsened diastolic function. LGE was common in our cohort and associated with worsened diastolic function. While clinical events were rare in our cohort, our data suggest incorporation of these CMR measures in risk stratification of pediatric patients with HCM.
- © 2013 by American Heart Association, Inc.