Sequential hybrid procedure for persistent atrial fibrillation

Abstract

Background: Catheter ablation of persistent atrial fibrillation yields an unsatisfactorily high number of failures. The hybrid approach has recently emerged as a technique that overcomes the limitations of both surgical and catheter procedures alone.

Methods and results: We investigated the sequential (staged) hybrid method, which consists of a surgical thoracoscopic radiofrequency ablation procedure followed by radiofrequency catheter ablation 6 to 8 weeks later using the CARTO 3 mapping system. Fifty consecutive patients (mean age 62±7 years, 32 males) with long-standing persistent atrial fibrillation (41±34 months) and a dilated left atrium (>45 mm) were included and prospectively followed in an unblinded registry. During the electrophysiological part of the study, all 4 pulmonary veins were found to be isolated in 36 (72%) patients and a complete box-lesion was confirmed in 14 (28%) patients. All gaps were successfully re-ablated. Twelve months after the completed hybrid ablation, 47 patients (94%) were in normal sinus rhythm (4 patients with paroxysmal atrial fibrillation required propafenone and 1 patient underwent a redo catheter procedure). The majority of arrhythmias recurred during the first 3 months. Beyond 12 months, there were no arrhythmia recurrences detected. The surgical part of the procedure was complicated by 7 (13.7%) major complications, while no serious adverse events were recorded during the radiofrequency catheter part of the procedure.

Conclusions: The staged hybrid epicardial-endocardial treatment of long-standing persistent atrial fibrillation seems to be extremely effective in maintenance of normal sinus rhythm compared to radiofrequency catheter or surgical ablation alone. Epicardial ablation alone cannot guarantee durable transmural lesions.

Clinical trial registration: URL: www.ablace.cz Unique identifier: cz-060520121617.

Keywords: hybrid approach; persistent atrial fibrillation; radiofrequency ablation; sequential; surgical treatment.

Figure 1.

Bipolar voltage map of the left atrium after epicardial radiofrequency thoracoscopic ablation, posterior view. A, All 4 pulmonary veins were found isolated, while a gap was found in the middle of the roof line allowing electrical activation of the posterior wall. Red dots show sites that were re‐ablated with endocardial touch‐up. B, Remapping after ablation revealed no potentials in the posterior wall, which confirmed a complete box‐lesion.

Figure 2.

Cardiac rhythm 6 to 8 weeks after the surgical thoracoscopic epicardial radiofrequency (RF) ablation and 3 and 12 months after the transvenous catheter ablation.

Figure 3.

Success rate of surgical thoracoscopic epicardial radiofrequency isolation of pulmonary veins, linear ablation lines connecting both superior and inferior pulmonary veins, and the trigone line connecting the right superior pulmonary vein across the left atrial roof toward the noncoronary aortic cusp as they were assessed (A) immediately after the ablation during surgery and (B) during the electrophysiological examination 6 to 8 weeks following the index procedure. Percentage of deployed left atrial appendage clips is also depicted (violet color). IVC indicates inferior vena cava; LIPV, left inferior pulmonary vein; LSPV, left superior pulmonary vein; NA, not applicable; RIPV, right inferior pulmonary vein; RSPV, right superior pulmonary vein; SVC, superior vena cava.

Figure 4.

Kaplan–Meier arrhythmia‐free survival during the mean follow‐up of 513±138 days. RFA indicates radiofrequency ablation.