Beta-blocker effects on postoperative atrial fibrillation

OBJECTIVES: To determine whether restarting of Beta Blocker following cardiac surgery would reduce the incidence and the severity of post-operative atrial fibrillation (AF). METHODS: 210 patients who underwent elective coronary artery bypass grafting were randomized to control (C) (n = 105) and Beta Blockers (BB) (n = 105) groups. Preoperatively all patients were on one type or another of betablockers. Postoperatively only the (BB) group received the medication. Both groups were well matched and had the same cardioplegic technique. RESULTS: It was found that; (1) post op (AF) developed in 40 patients of group (C) and in 18 patients of group (BB) P value < 0.02. (2) 73% of (AF) patients in group (C) and 81% in group (BB) were older than 70 years of age. (3) 76% of the (AF) in (BB) group versus 43% in (C) group were converted to sinus rhythm or to a stable controlled rhythm within 24 h or less. P value < 0.01. CONCLUSIONS: The results indicate that restarting the Beta Blockers in the post-operative period after coronary bypass grafts significantly control the incidence and the severity of atrial fibrillation. Also it confirms the strong relation between the older age and (AF) occurrence.