Cardiovascular magnetic resonance characteristics in children with hypertrophic cardiomyopathy.

BACKGROUND Cardiovascular magnetic resonance has provided important information on the diagnosis and risk stratification of hypertrophic cardiomyopathy (HCM) in adults; however, comparable data are absent for HCM in children. The study was performed to evaluate cardiovascular magnetic resonance characteristics in children with idiopathic HCM. METHODS AND RESULTS Cardiovascular magnetic resonance was performed in 71 consecutive children with idiopathic HCM (age, 12.8±4.1 years; 46 boys and 25 girls). The left ventricular (LV) parameters indexed by body surface area were calculated and compared with those in 71 healthy children (age, 13.1±3.3 years; 51 boys and 20 girls). Among those with HCM, concentric LV hypertrophy occurred in 9 patients (12.7%): in 2 children, it progressed into end-stage phase. The prevalence of late gadolinium enhancement (LGE) was 73%, and the extent of LGE was 10.4±8.3% of LV mass. Children with HCM with LGE had greater LV mass indexed (112.7±57.9 versus 70.3±37.4 g/m(2); P=0.025) but had no significant difference in maximal LV wall thickness indexed (19.4±6.3 versus 18.1±7.9 mm/m(2); P=0.513). In addition, the hazard ratio of adverse events for the extent of LGE was 1.1 (P=0.004). The follow-up (2.4±1.6 years) demonstrated that LGE was associated with adverse events in children with HCM (log-rank; P=0.029). CONCLUSIONS The prevalence and extent of LGE in children with HCM approximate to those in adults with HCM. Furthermore, children with HCM with LGE tend to have adverse events, and larger researches with longer follow-up are required.