Management of Hypertrophic Cardiomyopathy in Children

Abstract

Hypertrophic cardiomyopathy (HCM) is an inherited cardiac disease characterized by unexplained left ventricular hypertrophy, typically involving the interventricular septum. Hypertrophy may be present in infants, but commonly develops during childhood and adolescence. Management of children with HCM aims to provide symptomatic relief and prevention of sudden death, which is the primary cause of death. Unfortunately, no randomized comparative trials to date have assessed different treatment options in HCM. Medical treatment with negative inotropic agents (beta-adrenoceptor antagonists [beta-blockers], verapamil) is the first therapeutic choice in all symptomatic patients. Beta-blockers also appear to have prognostic merit in children. Surgical myectomy is effective in reducing symptoms in children with left ventricular (LV) obstruction who are unresponsive to medical treatment, although a repeat operation may be needed in a substantial proportion of patients due to relapse of LV obstruction. The recently introduced percutaneous septal ablation can also be regarded as a feasible alternative in this cohort. Technical limitations of both invasive therapeutic options should be carefully considered, preferably in experienced centers. Results of recent randomized trials indicate that dual chamber pacing, once considered a therapeutic option for patients with HCM, should only be used as treatment for conduction abnormalities. Regular clinical risk stratification for sudden death is of vital importance for the prevention of sudden death in young patients. Familial history of sudden death at a young age, LV hypertrophy >3 cm, unexplained syncope, nonsustained ventricular tachycardia in Holter monitoring, and abnormal blood pressure response during exercise are currently considered clinical risk factors for sudden death. Each factor has a low positive predictive accuracy, but patients having two or more of these risk factors are deemed as high risk. Secondary prevention of sudden death in patients successfully resuscitated from cardiac arrest and/or sustained ventricular tachycardia warrants treatment with an implantable cardioverter defibrillator (ICD). Primary prevention of sudden death in patients considered to be at high risk should aim at the management of obvious arrhythmogenic mechanisms (paroxysmal atrial fibrillation, sustained monomorphic ventricular tachycardia, conduction system disease, accessory pathway, myocardial ischemia), and the prevention and/or management of ventricular tachyarrhythmias with amiodarone and/or ICD implantation, respectively. The choice of treatment in children is greatly influenced by technical aspects, such as adverse effects of amiodarone, and ICD implantation difficulties or complications. Amiodarone could also be used as a bridge in children at high risk, until they reach adulthood, possibly achieving a lower risk status, or until their physical growth permits ICD implantation as long-term therapy.

Outcomes after implantable cardioverter-defibrillator treatment in children with hypertrophic cardiomyopathy

“…4 In our study, two of five patients receiving amiodarone experienced multiple appropriate ICD treatments. Although the numbers are small, this suggests that amiodarone does not prevent SCD in high-risk children.…”

Predictive genetic testing for cardiovascular diseases: Impact on carrier children

“…Lifestyle modifications include diet restrictions, exercise, and non-smoking (FH), and may involve avoiding trigger situations such as competitive sports (LQTS1, LQTS2), loud noises (LQTS2), swimming, and/or diving (LQTS1), avoidance of daily competitive sports (LQTS, HCM) [van Langen, 2005]. Preliminary studies, indicate such interventions to be effective in reducing the risk in children [Seggewiss and Rigopoulos, 2003;Wiegman et al, 2004;Goldenberg et al, 2008].…”

Alcohol septal ablation after myomectomy failure solutions for unusual cases

“…There is not a consensus as to the benefits of ASA in childhood. Some have ruled it out as an option [14] while others consider it a feasible alternative [15]. This is due to the limited experience with ASA in children suffering from HOCM refractory to clinical treatment.…”