Surgical Treatment of Atrial Fibrillation with Concomitant Mitral Valve Disease: An Asian Review

Atrial fibrillation (AF) is the most common sustained cardiacarrhythmia in patients with mitral valve disease and is presentin up to 50% of patients undergoing mitral valve surgery,contributing to increased risks of systemic embolization, anticoagulant-related hemorrhage and mortality. The Cox maze IIIprocedure, introduced in 1987 by Dr. James Cox, was the firsteffective operation for AF and is recognized as the gold standardtherapy for AF associated with organic heart disease.However, few surgeons have adopted the Cox maze III procedure,as it is a lengthy operation with extensive cutting, suturingand blood loss. Several groups in Asia have successfullydeveloped less invasive approaches using a number of differentenergy sources to create continuous lines of ablation to replacethe surgical incisions. Because high-density real-time intraoperativemapping to define the mechanisms of AF is currentlynot available to guide AF ablation in most surgical groups, an anatomic approach to ablationbased on our understanding of the pathophysiology and empiric results is reasonable. Thepreoperative left atrial size and duration of AF are primary predictors of sinus conversionafter the maze procedure for patients with persistent and permanent AF and mitral valve disease.The maze procedure combined with an atrial volume reduction technique may increasethe sinus conversion rate. Future progress will require a better understanding of the mechanismsof AF, and minimally invasive cardiac surgery with endoscopic AF ablation needs tobe explored in the Asian region.