Disopyramide as rescue treatment in a critically ill infant with obstructive hypertrophic cardiomyopathy refractory to beta blockers

Abstract

Hypertrophic obstructive cardiomyopathy (HOCM) is the most common known cause of sudden death in children beyond infancy and in young athletes. Cases reported indicate that steroid-induced HOCM is usually a benign disorder. The normalization of cardiac morphological changes and clinical signs observed after the discontinuation of steroid therapy indicates that the effects on cardiac muscle are dose-dependent and reversible. However, the management of patients with symptomatic-HOCM presenting in infancy represents a major challenge because left ventricular outflow tract obstruction is a major risk factor associated with increased mortality in pediatric patients. We report a critically ill infant with steroid-induced HOCM resistant to beta-blockers who was successfully treated with disopyramide without relevant adverse events. Adult guidelines and pediatric experts suggest pharmacological therapy with beta-blockers or verapamil as the first- and second-line approach. However, these drugs are not always an option, especially in critical patients, hence, alternative therapeutic options are required. For these cases, disopyramide could be an alternative drug in spite of the little evidence on its safety and efficacy in pediatric patients. Our experience supports this cause, and the need for prospective studies on its use in the management of hypertrophic cardiomyopathy in children.

<Learning objective: Patients with symptomatic-HOCM resistant to first-line therapy with beta-blockers represent a challenge and are often referred for advanced care. In children, many authors suggest that disopyramide in combination with beta-blockers could be a useful adjunct therapy option in these cases, resulting in decrease of left ventricular outflow tract obstruction, symptoms, and survival improvement, without significant pro-arrhythmia mortality.>