Abstract 4145534: Impact of operation related myocardial infarction on the clinical outcome of patients undergoing coronary endarterectomy combined with coronary artery bypass grafting

Background: Coronary endarterectomy (CE) combined with coronary artery bypass grafting (CABG) is one of the last revascularization options for patients with diffuse coronary artery disease. However, concerns exist regarding the application of CE due to the increased perioperative risk, including operation related postoperative myocardial infarction (POMI). However, the impact of POMI on the later outcome is unknown. Research question: Does POMI influence the follow-up clinical outcome of patients undergoing CE+CABG? Aims: To evaluate the impact of POMI on the patient outcome after CE+CABG. Methods: Patients who underwent CE+CABG (excluding concomitant valvular or ventricular aneurysm surgery) between September 2008 and January 2024 were retrospectively enrolled. POMI was defined according to the Forth Universal Definition of Myocardial Infarction. Patients were divided into POMI and no POMI group. Propensity score matching (PSM) analysis with 1:4 ratio was performed to balance the potential baseline confounders. Kaplan-Meier analysis and log-rank test was performed to test the survival difference between the two groups. Cox regression analysis was used to calculate the hazard ratios (HR) and 95% confidence intervals (CI).The primary outcome was the follow-up overall survival, and the secondary outcome was the survival free of major adverse cardiovascular and cerebrovascular events (MACCE), composite of all-cause death, myocardial infarction, stroke and repeat revascularization. Results: A total of 859 patients met the inclusion criteria, including 52 in the POMI group and 807 in the no POMI group. The mean age was 61.1±9.0 years, and 78.5% of them were male. During a median follow-up of 13.1 [6.2, 37.7] months, 28 (3.3%) of the patients suffered from death, while 66 (7.7%) suffered from MACCE. The PSM resulted in pairing of 52 and 208 patients in the two groups. The survivals differed significantly between the two groups ( Figure 1A & B ). Cox regression analysis revealed that POMI was observed to be associated with decreased overall (HR: 5.28, 95% CI:1.42-19.67, P=0.013) and MACCE-free (HR: 4.51, 95% CI: 1.69-12.01, P=0.003), which was in line with the unmatched analysis (Overall survival: P=0.001, MACCE-free survival: P=0.001). Conclusion: POMI after CE+CABG might impair the survival outcomes of patients.