Ventricular Tachyarrhythmias in Patients With Hypertrophic Cardiomyopathy and Defibrillators: Triggers, Treatment, and Implications
The mechanism of SCD in patients with HCM is thought to be ventricular fibrillation (VF), based largely on case reports and small series. The advent of the ICD has not only allowed effective prevention of SCD in patients with HCM, but has also provided the opportunity for investigation into the triggering and treatment of arrhythmias seen in these patients.
Previous data from our group has shown similar occurrence rates of ventricular tachycardia (VT) and VF in high‐risk patients with HCM and ICDs.1 Two prior smaller series of 9 patients with 51 episodes of ventricular arrhythmia12 and 29 patients with 56 arrhythmias13 showed a preponderance of monomorphic VT and conflicting data regarding the supraventricular rhythm preceding ventricular arrhythmias.
A relevant and timely issue is whether high adrenergic activities such as competitive sports should be avoided in patients with HCM.14 A recent registry demonstrated that patients with genetic cardiac diseases and ICDs could participate in sports without mortality, but with significant morbidity including ventricular arrhythmias and ICD shocks, both appropriate and inappropriate, associated with exercise.