Conduction disturbances after superior septal approach for mitral valve repair

Background. The superior septal approach sacrifices the sinus node artery, and it requires more invasive incisions into the right and left atria. Ther efore, postoperative rhythm disturbances could be troublesome in patients w ith SSA. In this study, we evaluated perioperative and midterm conduction d isturbances in the cardiac rhythms of patients who had a SSA for mitral val ve repair. Methods. Fifty-two patients had mitral valve operations by the superior sep tal approach, and cardiac rhythm status was assessed. The mean follow-up pe riod was 15 +/- 8 months. In patients with normal sinus rhythms preoperativ ely, serial changes in PR intervals were also assessed. Holter electrocardi ograms were used 6 to 12 months postoperatively. Twelve patients who had mi tral valve operations by conventional left atriotomy from the right side of the left atrium served as the control group. Results. There were no operative deaths, but one patient in the experimenta l group died of cerebral hemorrhage 4 months postoperatively. No intractabl e arrhythmias occurred. Of the 25 patients who maintained sinus rhythms, pr eoperative PR interval on electrocardiogram was 155 +/- 20 milliseconds. Po stoperative PR intervals increased for 1 week, had decreased within 2 weeks postoperatively, and returned to the normal range by 6 months postoperativ ely. Holter electrocardiograms of 17 patients did not show supraventricular arrhythmias exceeding 3% of the total beats. None of the patients needed p acemaker implantation. The PR intervals of 5 patients with normal sinus rhy thms in the control group did not show significant changes perioperatively. Conclusions. The superior septal approach is excellent for mitral valve ope rations because it overcomes postoperative dysrhythmias. (C) 1999 by The So ciety of Thoracic Surgeons.