Atrial fibrillation after coronary artery bypass grafting: a comparison of cardioplegia versus intermittent aortic cross-clamping

Supraventricular tachyarrhythmias following coronary artery bypass grafting are a common cause of postoperative morbidity, with a reported incidence of 10-40%. Two techniques of myocardial protection were assessed to determine their influence on the occurrence of postoperative supraventricular tachyarrhythmias. Group I (n = 82) received cold potassium cardioplegia combined with topical hypothermia and systemic cooling to 28 degrees C. Group II (n = 88) were protected by intermittent aortic cross-clamping with a systemic temperature of 32 degrees C. The overall incidence of atrial fibrillation/flutter was 22.3%. No significant difference was detected in the incidence of clinically important atrial fibrillation/flutter between the two groups [21/82 (25.6%) in group I versus 17/88 (19.3%) in group II, P > 0.25]. There was a positive association with age: in patients over 60 years the incidence of arrhythmias (31.8%) was significantly greater than in those less than 60 years (12.9%), P < 0.01. Sex, cardiopulmonary bypass times, aortic cross-clamp times, number of coronary grafts, end-operative creatine kinase myocardial band isoenzyme, right coronary endarterectomy and perioperative myocardial infarction had no association with the occurrence of postoperative atrial tachyarrhythmias.