Possibility of focal activation around the left upper pulmonary vein during chronic atrial fibrillation with mitral valve disease.

Focal regular activations were sometimes observed during chronic atrial fibrillation (AF) associated with mitral valve disease. We present a 58 year-old male diagnosed with mitral valvular stenosis and regurgitation with chronic atrial fibrillation. Intraoperative mapping of both atria was performed during mitral valvular surgery. Regular and repetitive activations around the left superior pulmonary vein were observed, in contrast to irregular and chaotic activations of the right atrium. This regular activation was supposed to be the focus of chronic AF. Surgical ablation of the posterior left atrium was successfully performed and eliminated the chronic AF, concomitant with mitral valve replacement.