Long-term follow-up of thoracoscopic ablation in long-standing persistent atrial fibrillation

Abstract

Objectives: Catheter ablation of long-standing persistent atrial fibrillation (LSPAF) remains challenging, with suboptimal success rates obtained following multiple procedures. Thoracoscopic ablation has shown effective at creating transmural lesions around the pulmonary veins and box; however, long-term rhythm follow-up data are lacking. This study aims, for the first time, to assess the long-term outcomes of thoracoscopic pulmonary vein and box ablation in LSPAF.

Methods: Rhythm follow-up consisted of continuous rhythm monitoring using implanted loop recorders or 24-h Holter recordings. Rhythm status and touch-up interventions were assessed up to 5 years.

Results: Seventy-seven patients with symptomatic LSPAF underwent thoracoscopic ablation in 2 centres. Freedom from atrial arrhythmias at 5 years was 50% following a single thoracoscopic procedure and 68% allowing endocardial touch-up procedures (performed in 21% of patients). The mean atrial fibrillation burden in patients with continuous monitoring was reduced from 100% preoperatively to 0.1% at the end of the blanking period and 8.0% during the second year. Antiarrhythmic drug use decreased from 49.4% preoperative to 12.1% and 14.3% at 2 and 5 years, respectively (P < 0.001). Continuous rhythm monitoring resulted in higher recurrence detection rates compared to 24-h Holter monitoring at 2-year follow-up (hazard ratio: 6.5, P = 0.003), with comparable recurrence rates at 5-year follow-up.

Conclusions: Thoracoscopic pulmonary vein and box isolation are effective in long-term restoration of sinus rhythm in LSPAF, especially when complemented by endocardial touch-up procedures, as demonstrated by the 68% freedom rate at 5 years. Continuous rhythm monitoring revealed earlier, but not more numerous documentation of recurrences at 5-year follow-up.

Keywords: Ablation; Atrial fibrillation; Long-standing persistent; Surgery; Thoracoscopy.

Figure 1:

Positioning of the Gemini-S ablation device to isolate the pulmonary veins and left atrial posterior wall.

Figure 2:

Freedom from all atrial arrhythmias after a single thoracoscopic ablation procedure only (single procedure freedom, blue line) or when allowing catheter touch-up procedures if required (multiple procedure freedom, measured from last procedure, red line).

Figure 3:

Rhythm status at 6 months and 1, 2 and 5 years following thoracoscopic ablation, including touch-up procedures and antiarrhythmic drug use. Patients at each timepoint are n = 76, n = 72, n = 57 and n = 35, respectively. AAD: antiarrhythmic drug; AF: atrial fibrillation.

Figure 4:

(A) Atrial arrhythmia recurrence rates after the thoracoscopic ablation procedure only, in intermittent (blue line) and continuous (red line) rhythm monitoring groups. (B) Landmark analysis of recurrence rates from baseline to medium-term (2 years) follow-up and from medium-term to long-term (5 years) follow-up between continuous and intermittent rhythm monitoring. CI: confidence interval; HR: hazard ratio.

Figure 5:

Atrial arrhythmia burden determined using continuous rhythm monitoring devices over the first 2 years following thoracoscopic ablation. (A) Changes in the average population burden following ablation. (B) Mean burden over the first 2 years following ablation per individual patient, ranked from highest to lowest.