The value of gamma glutamyl transpeptidase in atrial fibrillation following coronary artery bypass grafting

Abstract

Atrial fibrillation (AF) seen following open heart surgery is one of the complications with important conseqences in the short and long term. The exact cause is unknown, however oxidative stress has been postulated. In this study, the significance of serum gamma glutamyl transferase (GGT) as a predictor of oxidative stress was evaluated in cases who developed AF after coronary artery bypass grafting (CABG).One hundred patients undergoing CABG in the department of cardiovascular surgery at our hospital, were included in the study. Patients with chronic liver disease, atrial fibrillation prior to surgery, large left atrium (greater than 45 mm), the need for emergency surgery, thyroid dysfunction, were excluded from the study. Before operation all patients had echocardiographic examination, electrocardiograms taken, and blood samples drawn for routine biochemistry including GGT. Group 1 consisted of 36 patients, who developed AF; group 2 consisted of 64 patients who did not develop AF. Patients were seen at one month after surgery. Medical treatment was given to the group with AF. Beta blocker therapy was contiunued the same as prior to surgery. The groups were similar with respect to sex, cardiovascular risk factors, the extent of coronary artery disease (p>0.05). Age differed significantly between the groups (Table 1). Patients who developed AF within 48 hours after surgery had a tendency to have a higher level of GGT. The group with AF had a significantly higher level of AST (p=0.027) (Table 2). In this study, we found that patients undergoing coronary bypass surgery, who developed AF after surgery, had a tendency to have a higher level of GGT. Our finding suggests a need for larger prospective studies looking at the relationship of plasma GGT level as a predictor of oxidative stres and the development of AF after CABG.