Background: The debate on the best treatment strategy for atrial fibrillation (AF) has expanded following the introduction of the so-called “hybrid procedure” that combines minimally invasive epicardial ablation with endocardial catheter ablation. However, the advantage of the hybrid approach over conventional epicardial ablation remains to be established.

Methods: From June 2008 to December 2020, 609 surgical AF ablation procedures through a right minithoracotomy were performed at our institution. From 2008 to 2011, a unipolar radiofrequency (RF) device was used, whereas from 2011 to 2020 a bipolar RF device was used. In addition, between September 2016 and April 2017, 60 patients underwent endocardial completion of epicardial linear ablation. In 30 of these latter patients, surgical isolation of the Bachmann’s bundle (BB) was also performed. Starting from 2021, surviving patients at follow-up were asked to undergo electrocardiographic evaluation and left ventricular function assessment and to complete a questionnaire addressing quality of life and predisposing factors for recurrent AF.

Results: The ablation procedure was completed in all patients. Upon discharge, 30 (4.9%) patients showed recurrence of AF, whereas the remaining patients (95.1%) were in sinus rhythm. All patients in whom a hybrid approach was used either with or without BB ablation were discharged in sinus rhythm. After a mean follow-up of 74 months, 122 (20%) patients developed recurrent AF, including 19.9% in whom a unipolar RF device was used, 21% in whom a bipolar RF device was used, 23% who had undergone a hybrid procedure without BB ablation and 3.3% who had undergone a hybrid procedure with BB ablation. On multivariate analysis, reduced left ventricular ejection fraction, worsening of European Heart Rhythm Association symptom class, and cognitive impairment or depression during follow-up were found to be significantly associated with AF recurrence.

Conclusions: Surgical AF ablation through a right minithoracotomy is safe and may allow the creation of additional linear lesions, particularly in the BB. The placement of adjunctive linear lesions in the setting of a hybrid procedure can be more effective in reducing the risk for AF recurrence than isolated surgical ablation or hybrid ablation without the addition of further linear lesions, with no incremental risk to the patient. 

Keywords: Surgical ablation of atrial fibrillation, Catheter ablation of atrial fibrillation, Hybrid ablation of atrial fibrillation