Abstract
BACKGROUND: Although guidelines recommend preoperative stress testing for patients with risk factors, the appropriate indications for stress perfusion cardiac magnetic resonance (CMR) have not been clearly defined. This study aimed to investigate the value of preoperative stress perfusion CMR in predicting major adverse cardiovascular events (MACE) in patients undergoing major noncardiac surgery. METHODS: This study included 309 patients who underwent CMR within 180 days prior to major noncardiac surgery between 2010 and 2022. Patients were categorized based on the presence or absence of inducible myocardial ischemia. The primary outcome was MACE, defined as a composite of cardiovascular death, myocardial infarction, sustained ventricular arrhythmia, heart failure, or ischemic stroke occurring during the indexed hospitalization for surgery or within 30 days post-discharge. RESULTS: The mean patient age was 72 years (51% male), and 21% demonstrated inducible myocardial ischemia. Total MACE occurred in 4.5% of patients and was significantly higher in the inducible ischemia group compared to those without ischemia (16.9% vs. 1.3%, p < 0.001). Cox regression analysis identified inducible ischemia as the strongest predictor of MACE (hazard ratio [HR] 10.72, 95% confidence interval [95% CI] 2.91-39.60, p < 0.001). Other predictors included left ventricular ejection fraction (HR 0.94, 95% CI 0.92-0.97, p < 0.001), the number of ischemic segments (HR 1.19, 95% CI 1.07-1.31, p = 0.001), the presence of late gadolinium enhancement (LGE) (HR 6.28, 95% CI 1.93-20.44, p = 0.002), and the number of LGE segments (HR 1.21, 95% CI 1.08-1.37, p = 0.002). The predictive performance of the Revised Cardiac Risk Index score significantly improved after the addition of inducible ischemia (C-statistic 0.61 vs. 0.77; net reclassification improvement 0.58, p < 0.001; integrative discrimination index 0.07, p < 0.001). CONCLUSIONS: In this retrospective cohort study, inducible myocardial ischemia detected by stress perfusion CMR in patients undergoing major noncardiac surgery was associated with MACE during hospitalization or within 30 days post-discharge. Larger prospective or multicenter studies are required to validate these findings and ensure generalizability.