Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 49 2 2011 02 15 89 92 EN Hassan Radmehr Cardiovascular Surgery Department, Imam Khomeini Medical Center, Tehran University of Medical Sciences, Tehran, Iran. Seyed Khalil Forouzannia Cardiovascular Research Center, Afshar Hospital, Shahid Sadooghi University of Medical Sciences, Yazd, Iran. Ali Reza Bakhshandeh Cardiovascular Surgery Department, Imam Khomeini Medical Center, Tehran University of Medical Sciences, Tehran, Iran. Mehdi Sanatkar Cardiovascular Surgery Department, Imam Khomeini Medical Center, Tehran University of Medical Sciences, Tehran, Iran. 2015 09 28 This study evaluates the effect of preoperative increased level of serum creatinine (Cr) on early outcomes after coronary artery bypass graft surgery (CABG). 1140 patients who underwent CABG in our center were studied. Patients with Cr >2.25 mg/dl or preoperative dialysis and who had off-pump operations were excluded. Group 1 consisted of 892 patients with normal Cr (0.5-1.2 mg/dl) and group 2 consisted of 248 (21.8%) patients with mild increased level of serum Cr (1.3-2.2 mg/dl). Patients in group 1 were younger than group 2. There were more patients with hypertension in group 2, but there were not statistically significant difference between two groups in terms of the frequency of diabetes, smoking, cerebrovascular disease and New York Heart Association (NYHA) class. Left ventricular ejection fraction (LVEF) was lower in group 2. Cardiopulmonary bypass time (CPB) was longer in group 2. Early mortality was 3.2% in group 1 and 8.4% in group 2 (P<0.001). Prolonged ICU stay, low cardiac output, prolonged mechanical ventilation, postoperative atrial fibrillation, postoperative re-exploration and sepsis were more frequent in group 2. Mild increase in serum Cr level preoperatively is a marker of increased early mortality and outcome after CABG. https://acta.tums.ac.ir/index.php/acta/article/view/3699 https://acta.tums.ac.ir/index.php/acta/article/download/3699/3674