Clinical characteristics of hypertrophic cardiomyopathy in children: An 8‐year single center experience

Abstract Background Hypertrophic cardiomyopathy (HCM) is the second most common pediatric cardiomyopathy. Although there is a large body of literature about HCM in adults, there is limited information on HCM in childhood. We evaluated various aspects of pediatric HCM patients treated at our center. Methods We identified 152 pediatric patients with HCM between October 2011 and October 2019. Clinical history, invasive (ICD, pacemaker, electrophysiologic study, catheter ablation therapy) and non‐invasive (ECG, holter moniterization, echocardiography, cardiac MR, genetic study, medicam treatment) data were collected and evaluated. Results The mean ± standard deviation age of patients was 8.9 ± 5.7 years (1 month–18 years) and 67.8% were male. The most frequent clinical symptoms were murmur and palpitations. Three cases (2%) had aborted sudden death as the first manifestation of HCM. Of these patients, 120 (78.9%) had non‐syndromic HCM and 32 (27.2%) had syndromic HCM. Asymmetric septal hypertrophy was common (48.3%) in the non‐syndromic group, whereas concentric hypertrophy was common (56.2%) in syndromic group. Left ventricular outflow tract obstruction (LVOTO) occurred in 39 (25.6%) patients. Nine (5.9%) patients underwent electrophysiologic study and/or ablation and 16 patients underwent surgical intervention. Implantable cardioverter defibrillator (ICD) insertion was performed in 38 patients (26 transvenous, 12 epicardial). ICDs were inserted in three (7.9%) patients for secondary prevention; in the remaining patients (92.1%) the devices were placed for primary prevention. Mean SD follow‐up time was 27.1 ± 22 months. Five (3.3%) patients died during the follow‐up. No patient had heart transplantation or a long‐term assistive device. Conclusion The etiology of HCM is heterogeneous and present at any age. It is important to determine the timing of surgery and potential risks for sudden cardiac arrest. As most cases of HCM are familial, evaluation of family members at risk should be a routine component of clinical management.