Editorial on the article entitled "Surgical ablation of atrial fibrillation during mitral-valve surgery".

Atrial fibrillation (AF) is very commonly accompanied by mitral valve (MV) diseases. As hemodynamic overload on the left atrium (LA) either by regurgitant blood volume or by increased hydrostatic pressure secondary to mitral stenosis persists, atrial tissue undergoes pathologic changes such as enlargement of LA chamber, thinning of atrial wall and reduction in number of atrial myocytes, which are replaced by interstitial fibrosis. In addition to these arrhytmogenic environments in the atria, increased electrical autonomicity in the junction between pulmonary veins and LA leads to abnormal pacemaker activities, this now is regarded as the key culprit of AF. As many as 20-60% of patients undergoing MV surgeries are reported to have AF, and this coexisting AF has long been regarded as poor prognostic marker in patients undergoing MV surgeries (1). Thanks to longstanding dedicated efforts in cardiac surgical society initially propelled by Dr. James Cox, we now have a great solution to treat this disease—the Maze procedure (2).