Key Takeaways:
- The VANISH2 trial compared catheter ablation with systematic antiarrhythmic drug therapy as a first-line treatment strategy in patients with an ICD ischemic cardiomyopathy, and ventricular tachycardia who had no history of nonresponse to antiarrhythmic drug therapy.
- Catheter ablation significantly reduced the composite primary outcome (death, VT storm, ICD shock, and VT emergency treatment) compared with antiarrhythmic drug therapy (HR, 0.75; 95% CI, 0.58–0.97; P=0.03).
- Sustained VT requiring treatment below the detection limit of an ICD was notably reduced in the catheter ablation group (HR, 0.26; 95% CI, 0.13–0.55; P<0.001).
- Mortality rates were similar between groups, with no statistically significant difference (HR, 0.84; 95% CI, 0.56–1.24; P=0.38).
- Catheter ablation demonstrated a comparable safety profile, with fewer drug-related adverse events compared to antiarrhythmic drugs.
Ventricular tachycardia (VT) poses a major risk for patients with ischemic cardiomyopathy, often leading to recurrent ICD shocks and worse outcomes. Antiarrhythmic drugs such as sotalol and amiodarone are typically the first-line treatments, but they carry risks of systemic toxicity.
The Ventricular Tachycardia Antiarrhythmics or Ablation in Ischemic Heart Disease (VANISH) trial showed that ablation and continuation of baseline antiarrhythmic medications in patients with ventricular tachycardia and ischemic cardiomyopathy led to a lower risk of a composite of death, appropriate ICD shock, or ventricular tachycardia storm than escalation of antiarrhythmic drug therapy. The VANISH2 trial compared catheter ablation with systematic antiarrhythmic drug therapy as a first-line treatment strategy in patients with an ICD, ischemic cardiomyopathy, and ventricular tachycardia who had no history of nonresponse to antiarrhythmic drug therapy (ClinicalTrials.gov number, NCT02830360.) The results of this study were presented at AHA Scientific Sessions 2024 with simultaneous publication in the New England Journal of Medicine.
The VANISH2 trial was a multicenter, open-label randomized trial comparing catheter ablation with antiarrhythmic drug therapy (amiodarone or sotalol) in 416 patients with ischemic cardiomyopathy, ICDs, and recent VT episodes. Catheter ablation was performed within 14 days after randomization; sotalol or amiodarone was administered as antiarrhythmic drug therapy according to prespecified criteria. The primary endpoint was a composite of all-cause death, VT storm, ICD shocks, and sustained VT requiring medical intervention, measured over a median follow-up of 4.3 years. Secondary endpoints assessed individual components of the composite outcome and adverse events.
After a median of 4,3 years, the primary composite endpoint occurred in 50.7% of the catheter ablation group and 60.6% of the antiarrhythmic drug group (HR, 0.75; 95% CI, 0.58–0.97; P=0.03). Sustained VT requiring treatment below the detection limit of an ICD occurred in 4.4% of the catheter ablation group versus 16.4% in the antiarrhythmic drug group (HR, 0.26; 95% CI, 0.13–0.55; P<0.001). Rates of VT storm were 21.7% in the catheter ablation group and 23.5% in the drug group (HR, 0.95; 95% CI, 0.63–1.42; P=0.81), while ICD shocks occurred in 29.6% and 38.0%, respectively (HR, 0.75; 95% CI, 0.53–1.04; P=0.08). All-cause mortality was 22.2% in the catheter ablation group and 25.4% in the drug therapy group, with no significant difference (HR, 0.84; 95% CI, 0.56–1.24; P=0.38). Adverse events were reported in 28.1% of the catheter ablation group and 30.5% of the drug therapy group (P=0.62). Among catheter ablation patients, procedural complications included two deaths (1%) and nonfatal cardiac events, such as stroke and perforation, in 11.3% of patients. In the antiarrhythmic drug group, drug-related adverse events such as pulmonary toxicity and thyroid dysfunction occurred in 21.6% of patients, leading to treatment discontinuation in several cases.
Dr. John L. Sapp, the lead investigator, stated, “These results may change how heart attack survivors with ventricular tachycardia are treated. Currently, catheter ablation is often reserved as a last-resort therapy when antiarrhythmic medications fail or cannot be tolerated. Now we know that ablation is a reasonable option for first-line treatment.” These findings highlight catheter ablation’s effectiveness as an early intervention for VT management, offering an alternative to drug therapy.