Outcomes After Early Postoperative Myocardial Infarction Due to Graft Failure in Patients Undergoing Coronary Artery Bypass Grafting

Abstract

Background: Early graft failure (EGF) after coronary artery bypass grafting (CABG) occurs in up to 12% of grafts, but is often clinically unapparent. EGF may result in perioperative myocardial infarction with consequently increased mortality. The aim of the present study was to analyze the incidence of clinically apparent EGF in patients undergoing CABG and the influence on mortality.

Methods: We analyzed outcomes of consecutive patients undergoing CABG from January 2015 to December 2018 with respect to postoperative emergency coronary angiography (CAG) due to suspected EGF and 30-day mortality. Patients with CAG-documented EGF were matched to patients without EGF to examine predictors of mortality.

Results: The analysis included 5638 patients undergoing CABG. Eighty-six patients (1.5%) underwent emergency CAG due to suspected EGF. Clinically apparent EGF was observed in 61 of these patients (70.9%), whereas 14 (16.3%) had a culprit lesion in a native coronary artery. The majority of patients (n = 45; 52.3%) were treated with percutaneous coronary intervention and 31 (36%) underwent re-do CABG. The remaining patients were treated conservatively. The 30-day mortality rate of suspected EGF patients undergoing CAG was 22.4% (n = 19), which was higher than the mortality rate of 2.8% overall (P<.001); this remained higher after matching the EGF patients with the control group (11 [20.4%] vs 2 [4.0%]; P=.02).

Conclusion: Emergency CAG after CABG is rare and is primarily carried out in patients with EGF. The 30-day mortality rate of these patients is high, and EGF is an independent predictor of mortality. Perioperative CAG with subsequent treatment is mandatory in these patients.

Keywords: coronary artery bypass grafting; early graft failure; perioperative mortality; perioperative myocardial infarction.