The importance and the relationship of blood glucose level in the development of atrial fibrillation in coronary bypass surgery in diabetic patients

Aim: Currently, coronary artery bypass graft surgery (CABG) is the most commonly performed open heart surgery. Diabetes mellitus (DM) causes morbidity and mortality in patients undergoing CABG as in other surgeons. In this study, we aimed to explain the relationship between blood glucose level and Atrial Fibrillation (AF) after CABG operations in DM patients. Material and Method: In this study we included, 456 patients, whom underwent elective isolated CABG operation between January, 2015 and August 2017, retrospectively. 219 of these patients had DM. These patients were divided into two groups as Group 1 (no postoperative AF developed) and Group 2 (postoperative AF, developed). Preoperative demographics, amount of drainage after operation, amount of blood usage during and after operation were recorded and statistically evaluated. Results: Group 1 had 135 patients (58 F, 77 M) and Group 2 had 84 patients (31 F, 53 M). The mean time for the diagnosis of DM in patients was 5.2 ± 2.3 years in Group 1 and 6.7 ± 2.6 years in Group 2. 92 of the group 1 patients (68.2%) were receiving standard insulin therapy, 43 (31.8%) were receiving oral antidiabetic treatment, 65 of the group 2 patients (77.4%) were receiving standard insulin therapy, 19 (22.6%) were receiving oral antidiabetic treatment. There was no significant difference between the groups in terms of smoking habit, COPD and HT. The mean age was 62.4 ± 8.2 years in Group 1 and 61.5 ± 6.3 years in Group 2. Blood glucose levels of the patients were measured 182 ± 56 mg / dl preoperative, in perioperative period as 224 ± 48 mg / dl and 162 ± 41 mg / dl postoperatively in Group 1. Blood glucose levels of the patients in Group 2 were measured 210 ± 44 mg / dl preoperatively, 256 ± 38 mg / dl in perioperative period, 195 ± 63 mg / dl postoperatively. The mean duration of hospitalization in intensive care unit was 2.3 ± 0.5 days in Group 1 and 4.4 ± 1.2 days in Group 2. Conclusion: Diabetes mellitus is still an important risk factor for morbidity and mortality in coronary bypass surgery. Although not directly, increased glucose levels cause a significant increase in the rate of postoperative AF development. As a result of this study, lowering and following up of blood glucose levels in DM patients before and after the operation will decrease the rate of postoperative AF development and hence the duration of hospital stay and cost.