The following is a summary of “Use of class IC antiarrhythmic drugs in patients with structural heart disease and implantable cardioverter defibrillator,” published in the February 2024 issue of Cardiology by Zylla et al.

Researchers conducted a retrospective study to examine the contemporary usage of class IC antiarrhythmic drugs (AADs) in patients with structural heart disease (SHD) and implantable cardioverter defibrillator (ICD), considering diagnostic and therapeutic advancements in cardiovascular medicine.

They conducted a retrospective investigation analyzing outcomes in patients with SHD who had ICDs and received individualized therapy with class IC-AADs due to treatment failure, AEs, or unacceptable risks associated with alternative therapeutic options.

The results showed that among the fifty patients included from four tertiary centers (median age 48.5 years; 52% female), the most prevalent underlying SHD was dilated (42%) or ischemic cardiomyopathy (26%) with a median left ventricular ejection fraction (LVEF) of 45%. The indications for AAD therapy were sustained ventricular arrhythmias (VA) in 58% of cases, symptomatic premature ventricular contractions (26%), and atrial arrhythmias (16%). The median follow-up duration was 27.8 months. About 72% of patients achieved freedom from sustained VA, and 80% were free from receiving ICD therapy. In 38% of cases, AAD therapy was discontinued, with the most common reason being insufficient efficacy (n = 8). Pro-arrhythmia was suspected in three patients. During the follow-up period, five patients (10.0%) passed away, two of whom had cardiovascular causes (4.0%).

Investigators concluded that despite concerns, class-IC-AADs showed low pro-arrhythmic events and mortality in SHD patients with ICDs over 2 years, suggesting further research is warranted with modern cardiovascular therapies.

Source: link.springer.com/article/10.1007/s00392-024-02394-6