Indications to coronary artery bypass graft angiography in the early postoperative period

Aim . To determine indications to emergency coronary artery bypass angiography. Methods . 7,616 medical records of patients with coronary artery disease who underwent isolated CABG in the period from 2012 to 2019 at the Federal Center for Cardiovascular Surgery were reviewed. Of them, 103 (1.35%) patients underwent emergency coronary artery bypass graft angiography in the early postoperative period to verify signs of myocardial damage. Patients were assigned to two groups based on angiographic findings and selected treatment strategy. Out of 75 patients, 57 patients from Group 1 had no severe angiographic signs of occlusive changes of the grafts and native arteries. But 18 patients reported failed graft and required conservative management. Group 2 (n = 28) included patients who had failed coronary artery bypass grafts according to angiography findings. 20 patients underwent endovascular treatment, and 8 patients underwent repeated surgery. The control group included 30 patients (0.39%) without any signs of ischemic myocardial damage. Intraoperative flow was assessed as well as postoperative electrocardiographic and echocardiographic records. Biochemical markers of myocardial damage were measured. Results . Blood flow velocity was less than 20 ml/min, and the pulsatility index exceeded 3.0 according to the intraoperative flow assessment of coronary artery bypass grafts with impaired blood flow according to angiography findings. There was no relationship found between ischemic changes according to ECG, ECHO-CG, and angiographic findings. Significant differences were found in troponin I levels between Group 1 (patients with coronary artery graft dysfunction) and the control group (Group 3) at all time intervals (1, 6, 12, 24 and 48 hours). Conclusion . The predictors of failed coronary artery bypass grafts in the early postoperative period allowed identifying indications to emergency angiography.