RCT: Linear Ablation Plus Ethanol infusion of the vein of Marshall Enhances Rhythm Outcomes in Persistent AF
20 Nov, 2024 | 15:48h | UTCBackground: Pulmonary vein isolation (PVI) is the cornerstone of catheter ablation for atrial fibrillation (AF) but has modest efficacy in persistent AF. Previous randomized trials have not demonstrated additional benefit from adding linear ablation to PVI, possibly due to challenges in achieving durable lesions. Ethanol infusion of the vein of Marshall (EIVOM) may facilitate linear ablation, especially at the mitral isthmus, potentially improving outcomes.
Objective: To determine whether adding linear ablation combined with EIVOM to PVI improves maintenance of sinus rhythm compared with PVI alone in patients with persistent AF.
Methods: PROMPT-AF was an investigator-initiated, multicenter, open-label randomized trial involving 12 hospitals in China. The study included 498 patients aged 18–80 years with persistent AF lasting >3 months undergoing first-time ablation. Participants were randomized to either PVI alone or PVI plus EIVOM and linear ablation targeting the left atrial roof, mitral isthmus, and cavotricuspid isthmus. Primary outcomes included freedom from atrial arrhythmias lasting >30 seconds without antiarrhythmic drugs over 12 months. Patients were monitored weekly with wearable ECG patches and periodic Holter monitoring.
Results: Among 495 patients analyzed (mean age, 61.1 years; 72.9% male), the intervention group demonstrated significantly higher freedom from atrial arrhythmias without antiarrhythmic drugs (70.7% vs 61.5%; HR, 0.73; 95% CI, 0.54–0.99; P = .045). Secondary outcomes showed no significant differences in quality of life or arrhythmia recurrence with antiarrhythmic drugs. Linear ablation increased procedural time (188.0 vs 140.8 minutes, P < .001) and fluoroscopy exposure. Serious adverse events were comparable between groups, though pericarditis or pericardial effusion occurred in 7 intervention patients versus none in the control.
Conclusions: Adding linear ablation and EIVOM to PVI significantly improves freedom from atrial arrhythmias in patients with persistent AF compared with PVI alone.
Implications for Practice: The combination of linear ablation and EIVOM addresses limitations of PVI alone by enhancing lesion durability and targeting challenging areas such as the mitral isthmus. However, the increased procedural complexity and longer operative times highlight the need for skilled operators. Adoption should be balanced against risks and resource demands.
Study Strengths and Limitations: Strengths include the randomized, multicenter design and high procedural adherence. Limitations involve the open-label design and potential underestimation of arrhythmia recurrence due to intermittent rhythm monitoring rather than continuous monitoring. The increased procedural time and fluoroscopy exposure are concerns, and the findings may not be generalizable to all persistent AF patients, especially those with episodes lasting less than 3 months.
Future Research: Further studies are needed to optimize ablation strategies, assess long-term outcomes, and evaluate the safety, efficacy, and cost-effectiveness of incorporating EIVOM and linear ablation in diverse patient populations.