Ventricular arrhythmia following alcohol septal ablation for obstructive hypertrophic cardiomyopathy

Area of Science:

• Cardiology
• Electrophysiology
• Interventional Cardiology

Background:

• Obstructive hypertrophic cardiomyopathy (HCM) is a significant cause of sudden cardiac death (SCD).
• Alcohol septal ablation (ASA) is a nonsurgical treatment option for symptomatic, drug-refractory obstructive HCM.
• The long-term impact of ASA on ventricular arrhythmia risk remains incompletely understood.

Purpose of the Study:

• To evaluate the risk of SCD and ventricular arrhythmias following ASA in patients with obstructive HCM.
• To assess the incidence of ventricular tachycardia/ventricular fibrillation (VT/VF), cardiac arrest, or appropriate implantable cardioverter defibrillator (ICD) therapy post-ASA.

Main Methods:

• Retrospective analysis of 89 patients who underwent ASA for obstructive HCM.
• Secondary endpoint analysis focused on 42 patients with implanted ICDs or permanent pacemakers.
• Patients were stratified into high-risk and low-risk groups based on established ICD implantation criteria.
• Correlation of immediate post-ASA gradient with arrhythmic events was examined.

Main Results:

• No deaths attributed to SCD were observed during a mean follow-up of 5.0 years.
• The overall annual event rate for VT/VF, cardiac arrest, or appropriate ICD therapy was 4.9% in the device cohort.
• Low-risk patients had an annual event rate of 2.8%, while high-risk patients experienced a rate of 13.4%.
• An increase in the post-ASA gradient was significantly associated with an increased risk of arrhythmic events (HR 2.66, p <0.001).

Conclusions:

• ASA can be performed in highly symptomatic, drug-refractory obstructive HCM patients with no SCD mortality.
• The annual incidence of significant ventricular arrhythmias or appropriate ICD therapy is 4.9% in patients with implanted devices.
• Risk stratification and gradient monitoring may be important in managing patients post-ASA.