Corridor procedure--surgical option for treatment of chronic atrial fibrillation in patients undergoing mitral valve replacement.

The aim of this study was to determine the effectiveness of the 'corridor' procedure when added to mitral valve replacement in restoring and maintaining sinus rhythm in patients with chronic atrial fibrillation resulting from rheumatic mitral valve disease. Twenty-two patients with rheumatic mitral valve disease and chronic atrial fibrillation with fast, irregular ventricular response were divided into two groups. In the first group (n = 12), mitral valve replacement was combined with sinus node-AV node isolation ('corridor'): in the second, control group (n = 10), mitral valve replacement was performed through the left atriotomy. The effectiveness of the 'corridor' procedure on heart rhythm was analysed by: (i) 24-h Holter monitoring performed before and during 72 h after surgery, at hospital discharge, and 2 months later; and (ii) postoperative electrophysiological studies using temporary epicardial wires on each isolated atrial compartment. Immediately after surgery and in the following 2 months, heart rate variability analysis showed significantly lower hourly ventricular rates and rate variations in the 'corridor' group compared with those of the control group (P < 0.01). A significant difference was also found when comparing postoperative to preoperative findings in the corridor group (P < 0.05). In the control group, however, no significant differences (P > 0.05) were found concerning pre- and postoperative ventricular rate variations. At hospital discharge, nine of 12 patients with 'corridor' procedure were in sinus rhythm. Control patients remained in atrial fibrillation with irregular ventricular rate. The 'corridor' procedure, when added to mitral valve replacement, prolonged surgery, but led to restoration and long-term maintenance of sinus rhythm in 75% of patients with chronic atrial fibrillation and rheumatic mitral valve disease.