Catheter Ablation or Antiarrhythmic Drugs for Ventricular Tachycardia
John L Sapp1, Anthony S L Tang2, Ratika Parkash1
1QEII Health Sciences Centre, Dalhousie University, Halifax, NS, Canada.
Insights
Catheter ablation significantly reduced the risk of adverse events in patients with ischemic cardiomyopathy and ventricular tachycardia compared to antiarrhythmic drugs. This initial strategy offers a safer and more effective treatment option for managing this high-risk patient group.
Area of Science:
- Cardiology
- Electrophysiology
- Clinical Trials
Background:
- Patients with ischemic cardiomyopathy and ventricular tachycardia face high risks of adverse outcomes.
- Antiarrhythmic drugs are a common treatment, but their efficacy in suppressing ventricular tachycardia is often limited.
- The comparative effectiveness of catheter ablation versus antiarrhythmic drugs as a first-line therapy remains uncertain.
Purpose of the Study:
- To compare the efficacy and safety of catheter ablation versus antiarrhythmic drug therapy as a first-line treatment for ventricular tachycardia in patients with ischemic cardiomyopathy.
Main Methods:
- An international randomized trial assigned 416 patients with myocardial infarction and significant ventricular tachycardia to either catheter ablation or antiarrhythmic drug therapy (sotalol or amiodarone).
- All patients were equipped with an implantable cardioverter-defibrillator (ICD).
- The primary endpoint was a composite of all-cause death or, more than 14 days post-randomization, ventricular tachycardia storm, appropriate ICD shock, or sustained ventricular tachycardia requiring medical intervention.
Main Results:
- After a median follow-up of 4.3 years, the primary endpoint occurred in 50.7% of patients in the catheter ablation group versus 60.6% in the drug therapy group (hazard ratio, 0.75; P=0.03).
- Adverse events within 30 days post-procedure in the ablation group included death (1.0%) and nonfatal events (11.3%).
- Adverse events attributed to antiarrhythmic drugs in the drug therapy group included death (0.5%) and nonfatal events (21.6%).
Conclusions:
- An initial strategy of catheter ablation demonstrated a lower risk of the composite primary endpoint compared to antiarrhythmic drug therapy in patients with ischemic cardiomyopathy and ventricular tachycardia.
- Catheter ablation appears to be a more effective first-line treatment for this patient population.
Background:
Patients with ventricular tachycardia and ischemic cardiomyopathy are at high risk for adverse outcomes. Catheter ablation is commonly used when antiarrhythmic drugs do not suppress ventricular tachycardia. Whether catheter ablation is more effective than antiarrhythmic drugs as a first-line therapy in patients with ventricular tachycardia is uncertain.
Methods:
In an international trial, we randomly assigned in a 1:1 ratio patients with previous myocardial infarction and clinically significant ventricular tachycardia (defined as ventricular tachycardia storm, receipt of appropriate implantable cardioverter-defibrillator [ICD] shock or antitachycardia pacing, or sustained ventricular tachycardia terminated by emergency treatment) to receive antiarrhythmic drug therapy or to undergo catheter ablation. All the patients had an ICD. Catheter ablation was performed within 14 days after randomization; sotalol or amiodarone was administered as antiarrhythmic drug therapy according to prespecified criteria. The primary end point was a composite of death from any cause during follow-up or, more than 14 days after randomization, ventricular tachycardia storm, appropriate ICD shock, or sustained ventricular tachycardia treated by medical intervention.
Results:
A total of 416 patients were followed for a median of 4.3 years. A primary end-point event occurred in 103 of 203 patients (50.7%) assigned to catheter ablation and in 129 of 213 (60.6%) assigned to drug therapy (hazard ratio, 0.75; 95% confidence interval, 0.58 to 0.97; P = 0.03). Among patients in the catheter ablation group, adverse events within 30 days after the procedure included death in 2 patients (1.0%) and nonfatal adverse events in 23 patients (11.3%). Among the patients assigned to drug therapy, adverse events that were attributed to antiarrhythmic drug treatment included death from pulmonary toxic effects in 1 patient (0.5%) and nonfatal adverse events in 46 patients (21.6%).
Conclusions:
Among patients with ischemic cardiomyopathy and ventricular tachycardia, an initial strategy of catheter ablation led to a lower risk of a composite primary end-point event than antiarrhythmic drug therapy. (Funded by the Canadian Institutes of Health Research and others; VANISH2 ClinicalTrials.gov number, NCT02830360.).
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