부산대학교 도서관

Introduction: Hypertrophic cardiomyopathy (HCM) accounts for nearly half of pediatric cardiomyopathies. While impaired exercise function has been described in adults with HCM, little is known about exercise function in children with HCM.Hypothesis: Children with HCM have impaired exercise function.Methods: A retrospective cohort study was performed. Pts <21 years with a diagnosis of HCM with a cardiopulmonary exercise test (CPET) between November 1, 2002 and May 31, 2019 were included. Pts with syndromic HCM were excluded. CPETs with respiratory exchange ratio <1.09 were excluded. We compared indices of exercise performance to established population normal values using one-sample T-tests. In pts with multiple CPETs, we compared indices of exercise performance from the first to last CPET using paired T-tests.Results: We identified 124 pts with 240 CPETs. The average age at time of CPET was 14.8 ± 3.0 years. Average %predicted peak VO2 (78 ± 20%) was significantly less than the population average (p <0.01), though there was wide variability (range 35-152% predicted). Peak VO2 was <85% predicted in 67%, <50% predicted in 7%, and absolute peak VO2 was <25 cc/kg/min in 30% of tests. However, %predicted peak VO2 was >100% in 13% of tests. The %predicted peak O2 pulse (88 ± 21%; p <0.01; a surrogate for the forward stroke volume at peak exercise) and the %predicted peak heart rate (88.0 ± 12%; p <0.01) were significantly lower than established population normal values. In 63 pts with multiple CPETs, significant declines in %predicted peak VO2 (83 ± 20% v. 75 ± 19%; p <0.01) and O2 pulse (92 ± 22% v. 86 ± 21%; p <0.01) were observed at an average interval of 4.5 years. We found no statistically significant association between %predicted peak VO2 and interventricular septal thickness, resting left ventricular outflow tract gradient or echocardiographic indices of diastolic left ventricular function.Conclusions: Exercise function is at least moderately impaired in a substantial portion of children with HCM and this impairment tends to worsen over time. However, there is a significant subset of patient with remarkably well-preserved exercise function. Echocardiographic measurements did not correlate with exercise function in our cohort.