A Prospective, Multicentre Randomised Controlled Trial Comparing Catheter Ablation Versus Antiarrhythmic Drugs in
, Richard G Bennett1, Timothy Campbell1
1Department of Cardiology, Westmead Hospital, Westmead Applied Research Centre, University of Sydney, Sydney, NSW, Australia.
Insights
Catheter ablation (CA) may be superior to antiarrhythmic drugs for controlling ventricular tachycardia (VT) in structural heart disease patients. This trial compares CA to medical therapy for VT in this population.
Area of Science:
- Cardiology
- Electrophysiology
- Clinical Trials
Background:
- Catheter ablation (CA) has shown superiority over medical therapy for ventricular tachycardia (VT) in patients with ischemic heart disease.
- The efficacy of CA for VT in patients with diverse structural heart disease (SHD), including non-ischemic forms, remains unclear.
Purpose of the Study:
- To determine if catheter ablation (CA) is more effective than medical therapy in controlling ventricular tachycardia (VT) during follow-up in patients with structural heart disease (SHD).
Main Methods:
- A multicenter, randomized controlled trial involving 162 patients with SHD and VT.
- Participants were randomized 1:1 to undergo early catheter ablation or initial antiarrhythmic drug therapy.
- The study included a median follow-up of 18 months.
Main Results:
- The primary endpoint is a composite of recurrent VT, VT storm, or death.
- Secondary outcomes include individual primary endpoints, VT burden, cardiovascular hospitalizations, and mortality.
- Left ventricular ejection fraction (LVEF) will be assessed over 36 months.
Conclusions:
- The Catheter Ablation versus Anti-arrhythmic Drugs for Ventricular Tachycardia (CAAD-VT) trial aims to clarify the role of CA in managing VT in SHD patients.
- Results will inform treatment guidelines for VT in this complex patient group.
Importance:
Randomised trials have shown that catheter ablation (CA) is superior to medical therapy for ventricular tachycardia (VT) largely in patients with ischaemic heart disease. Whether this translates to patients with all forms and stages of structural heart disease (SHD-e.g., non-ischaemic heart disease) is unclear. This trial will help clarify whether catheter ablation offers superior outcomes compared to medical therapy for VT in all patients with SHD.
Objective:
To determine in patients with SHD and spontaneous or inducible VT, if catheter ablation is more efficacious than medical therapy in control of VT during follow-up.
Design:
Randomised controlled trial including 162 patients, with an allocation ratio of 1:1, stratified by left ventricular ejection fraction (LVEF) and geographical region of site, with a median follow-up of 18-months and a minimum follow-up of 1 year.
Setting:
Multicentre study performed in centres across Australia.
Participants:
Structural heart disease patients with sustained VT or inducible VT (n=162).
Intervention:
Early treatment, within 30 days of randomisation, with catheter ablation (intervention) or initial treatment with antiarrhythmic drugs only (control).
Main Outcomes, Measures, And Results:
Primary endpoint will be a composite of recurrent VT, VT storm (≥3 VT episodes in 24 hrs or incessant VT), or death. Secondary outcomes will include each of the individual primary endpoints, VT burden (number of VT episodes in the 6 months preceding intervention compared to the 6 months after intervention), cardiovascular hospitalisation, mortality (including all-cause mortality, cardiac death, and non-cardiac death) and LVEF (assessed by transthoracic echocardiography from baseline to 6-, 12-, 24- and 36-months post intervention).
Conclusions And Relevance:
The Catheter Ablation versus Anti-arrhythmic Drugs for Ventricular Tachycardia (CAAD-VT) trial will help determine whether catheter ablation is superior to antiarrhythmic drug therapy alone, in patients with SHD-related VT.
Trial Registry:
Australian New Zealand Clinical Trials Registry (ANZCTR) TRIAL REGISTRATION ID: ACTRN12620000045910 TRIAL REGISTRATION URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=377617&isReview=true.
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