morbidity. New–onset of atrial fibrillation is the most common arrhythmic complication after coronary artery bypass graft surgery and it may result

in haemodynamic compromise, thrombotic events, anxiety, and thus a prolonged hospitalization.

Materials and methods: A prospective study was performed in the Institute of Cardiovascular Diseases and Transplantation of Tirgu Mures,

Romania. We collected data between January and June 2017. For statistical analysis T–test and Fisher–test (GraphPad Prism 6.0 software, GraphPad

Software, Inc, La Jolla, CA 92037 USA) were used. Significance level was set at p<0.005.

Results: In the arrhythmic group, the mean age was higher than in the control group. The ejection fraction was lower in the arrhytmic group. In the

arrhytmic group more cases needed higher doses of inotropic drugs than in the control group. The arrhytmic group presented statistically significant

hemodynamic and renal postoperative complications.

Discussion: Cardiac dilatation, myocardial atrophy, decrease of conduction tissue and atrial fibrosis caused by aging may be responsible for the

increased risk of atrial fibrillation after CABG. Echography findings that suggested the increased risk of atrial fibrillation in the postoperative

period was the enlarged atrium. The blood supply to the right atrium, the sinoatrialnode and the atrioventricular node is mainly conveyed via the

right coronary artery, thus the stenosis of the right coronary artery may be a predictor. The statistically significant hemodynamic and renal

postoperative complications in our study are among the most common postoperative complications described in the literature.

Conclusions: Postoperative atrial fibrillation is more frequent in the elderly patients (above 60 years) with increased left atrium. Other

disturbances that predispose to this arrhythmia are: hypoxia and metabolic acidosis.