Inpatient vs Delayed Readmission for Coronary Artery Bypass Grafting After Non-ST Elevation Myocardial Infarction.

Abstract

The optimal timing of coronary artery bypass grafting (CABG) after non-ST elevation myocardial infarction (NSTEMI) remains debated. We assessed national practice patterns and outcomes of CABG timing after NSTEMI, including inpatient vs delayed surgery, and specific timing of inpatient surgery. Medicare beneficiaries aged ≥65 years presenting nonelectively with NSTEMI who underwent diagnostic angiography from October 2016 to October 2021 were identified. Patients undergoing percutaneous coronary intervention during the index admission and those who died before any revascularization were excluded. Patients undergoing inpatient CABG were compared with those discharged and returning for elective CABG within 3 months using propensity score matching, with a primary end point of 30-day mortality and a secondary end point of 4-year survival. Among inpatient CABG patients, 30-day mortality of patients undergoing intervention at 0 to 1, 2 to 3, 4 to 7, and >7 days after diagnosis was assessed with logistic regression with natural cubic splines. Of 704,638 patients with NSTEMI who underwent angiography, 90,551 (27.1%) underwent inpatient CABG and 5715 (2.3%) returned for elective CABG. After propensity matching, 30-day mortality was lower with elective readmission (3.6% vs 4.9%, P < .001), although 4-year survival was similar (P = .553). Among discharged patients, 1.3% required urgent CABG (30-day mortality of 6.3%) and 9.1% died without revascularization within 3 months. Among inpatient CABG patients, optimal short-term outcomes were observed at 2 to 4 days after angiography. Optimal CABG outcomes after NSTEMI occur when surgery is performed 2 to 4 days after diagnosis. Although delayed elective CABG offers short-term survival advantages in highly-selected patients, the risk of mortality and urgent intervention in discharged patients suggest most should undergo inpatient revascularization.