Use of Metoprolol for Prevention of Atrial Fibrillation After Coronary Bypass

Although atrial fibril lation co ınpromi ses left ventricular funct ion in patie nts with Ieft ventricular dysfunction (L VD), it is not known whether or not L VD has any direct effect on atrial fibrillation occurrence. Beta blackers are the most comınan drugs used in atrial fibrill ation prophylaxis. The ai m of this study was to investigate the atrial fibrillation occ urrence in patients unde rgoing coronary artery bypass grafting (CABG) surgery and the prophylactic effect of metoprolol in these cases. In this pros pective study, 526 patients who underwent CABG surgery were included, 253 of them with high left ventricular performance score (Group I) and 273 with normal left ventricular performance score (Group ll). Metoprolol was given 80 patients in group I and I 15 patients in group II in the postoperative period. The remaining patients (173 in group I, 158 in group Il) were not given any antiarrhythmic drugs. In pat ients wi th impaired le ft ventricular performance, atrial fibri llation occured 5 patients in g roup la (6.3%), and 28 patients in group Ib (16.2%). In patients with normal ventric ular performance, 6 patients in group Ila (5.2%) and 24 patients in group Ilb (15.2 %) atrial fibrillation was encountered (p<0.05). In both groups, mean occurrence time of atr ial fibrillat ion was the second postoperative day (p>0.05). Although duration of intensive care unit was s iınil ar in all groups (p>0.05), hos pitalization time was significantly longer in patients with atrial fib rillation than those of patients with normal sinus rhythm (p<0.05). In conclusion, the use of metoprolol was effective for preventing atrial fibrillation after CABG surgery e ither in. patients with normal or in paticnts wi th impaired left ventricular function. On the other hand, development of atrial fibril lation prolongs the hospitali zation durat ion, but not the stay in the intensive care unit after CABG surgery.