Initial Experience of Non-Atriotomy Surgical Ablation During Coronary Artery Bypass Grafting With Preexisting Atrial Fibrillation: A Multicenter Study

<h2>Abstract</h2><h3>Background</h3> Guideline concordance with surgical ablation in patients undergoing isolated coronary artery bypass grafting (CABG) is poor. Additional atriotomy and safety concerns are barriers to ablation. We sought to evaluate the initial safety and associated rhythm outcomes of a novel non-atriotomy surgical ablation (NASA) left atrial box lesion in patients undergoing isolated CABG. <h3>Methods</h3> A multicenter retrospective review included all concomitant NASA in patients with preexisting atrial fibrillation undergoing isolated CABG. The primary outcome was NASA-related intraoperative complications. Associated rhythm outcomes were per the Heart Rhythm Society definition of freedom from atrial fibrillation, atrial flutter, and atrial tachycardia (FFAF) <30 seconds at 12 months off class I or III antiarrhythmic medications by >24-hour continuous monitoring. Data are reported as median (interquartile range). <h3>Results</h3> Ninety-seven patients were analyzed. The median age was 73 (68-76) years; CHA₂DS₂-Vasc score, 4.0 (3-5); left ventricular ejection fraction, 55% (45%-60%); and left atrial diameter, 4.0 (3.6-4.7) cm. Most patients (86% [83/97]) had paroxysmal atrial fibrillation. The primary safety outcome of intraoperative complications attributed to NASA was not observed (0% [0/97]). Thirty-five patients (35/97 [36%]) had at least 12 months (median, 12 months; interquartile range, 12-24 months) of continuous ambulatory monitoring, and FFAF was 94% (33/35); 91% (29/32) showed FFAF off antiarrhythmic medications. <h3>Conclusions</h3> In patients with mostly paroxysmal atrial fibrillation undergoing isolated CABG surgery, concomitant NASA was safe and associated with favorable restoration of normal sinus rhythm at 1 year.