Surgical Treatment of Atrial Fibrillation

Abstract

Atrial fibrillation (AF) is the most common chronic arrhythmia in the adult population. Ablation lines have largely replaced the historical and challenging cut and sew techniques. Surgical ablation of AF is commonly performed in cases with other indications for cardiac surgery and less commonly as a stand-alone therapy. Pulmonary vein isolation is the cornerstone of this procedure. Extended left atrial ablation lines may increase efficacy in cases with longstanding persistent or permanent AF. Additional efficacy by adding right atrial ablation is controversial but is often performed in cases undergoing right atrial or atrial septal surgery. Left atrial volume reduction is recommended in cases with large left atria and AF undergoing another cardiac surgery. Arrhythmia recurrence is not uncommon after surgical ablation of AF and varies among studies due to heterogeneity in patient population, lesion set and endpoints. Freedom from AF recurrence was 65-87% at 12 months and 58-70% at 2 years follow-up. Long-term monitoring is recommended due to an increased prevalence of asymptomatic recurrences. The strongest predictors of AF recurrence are longstanding or persistent AF and a large left atrium. The most common mechanisms of recurrence are pulmonary vein reconnection, nonpulmonary vein triggers, and gaps in the ablation lines. About 20% of atrial tachyarrhythmia recurrences are atrial flutter or atrial tachycardia. There are not enough data in the surgical literature to support withdrawal of anticoagulation after surgical AF ablation. Patients selected for stand-alone surgical ablation usually have low risk profiles and low postoperative mortality rates (0.2%).

Late Results of Cox Maze III Procedure in Patients with Atrial Fibrillation Associated with Structural Heart Disease

“…Up to 3 months after surgical treatment of AF, the substrates and triggers of recurrent atrial tachyarrhythmias may be different from the determinants of baseline arrhythmia and, for this reason recurrences within this period may not be considered a therapeutic failure per se . 19 …”

“…However, so far, there has been no strong evidence for interruption of oral anticoagulation in the postoperative period of surgical repair of AF, regardless of maintenance of sinus rhythm. 19 Decision on the suspension of anticoagulation should be individualized.…”

“…It is known that, despite sinus rhythm recovery, a group of patients does not show any improvement of left atrial contractile function, which may result from scars and electrical isolation areas created during the procedure. 19 …”

Myricetin inhibits Kv1.5 channels in HEK293 cells

“…Catheter ablation has been proposed as an effective nonpharmacological alternative for AF that is often, however not always, the second-line treatment (28). In addition, surgical ablation of AF is commonly performed in cases with other indications for cardiac surgery and it is limited to cases with low surgical risk (29). However, non-drug treatments are limited by factors including their indications, medical conditions and costs.…”