Six-months results after left atrial Cox-maze like procedure using bipolar irrigated radiofrequency ablation for treatment of permanent atrial fibrillation

Objective: The purpose of this study was to assess the safety and results of Cox mini-maze lesion set using bipolar irrigated radiofrequency for left atrial (LA) ablation in patients with permanent atrial fibrillation (AF) undergoing open heart surgery. Methods: Forty nine patients (69 years) underwent a Cox-maze like LA procedure using the Cardioblate bipolar device (Medtronic, Minneapolis, MN, USA). Mean duration of permanent AF was 64.4 months and mean LA diameter was 51mm. Lesion set consisted of en-bloc ablation of the right and left pulmonary veins (PV), a line between both islands of PV, a circumferential lesion at the base of the LA appendage, a connecting line between the basis of the LA appendage and the ostium of the left superior PV and a LA isthmus line including the coronary sinus. The LA appendage was excluded. The ablation procedure was performed concomitant to coronary (n=7), mitral valve (n=17), aortic valve surgery (n=3), and combined procedures (n=22). Results: Average ablation time was 17.7 minutes. In 3 patients a permanent pacemaker was necessary but there were no other associated complications to the ablation procedure. In-hospital mortality was 2.1% (n=1). At six-months follow-up 82.2% of patients (n=37) were in sinus rhythm and presented a substantial LA contraction. There were 3 late deaths (6.2%). Conclusions: Bipolar irrigated radiofrequency ablation using a Cox-maze like lesion set for treatment of permanent AF during concomitant cardiac procedures is safe and effective, with 82.2% of patients free from AF at six months follow-up.