Abstract 20317: Stress-Induced Ischemia Does Not Risk Stratify Patients Prior to Vascular Surgery and is Not Associated With Elevated Post Operative Troponin

IntroductionImaging-based stress testing is used to risk stratify patients undergoing vascular surgery, though the evidence is limited. We aim to assess whether ischemia provides prognostic value for post-operative events and is associated with elevated troponin.MethodsConsecutive patients with imaging stress tests prior to vascular surgery were included. Clinical risk was determined by the revised cardiac risk index (RCRI). The primary outcome was post-operative myocardial infarction, heart failure, arrhythmia, or death within 30 days. The secondary outcome was elevated troponin.ResultsAmong 688 patients, 7.6% had exercise radionuclide imaging, 14.4% exercise echocardiography, 19.3% dobutamine echocardiography, and 58.7% vasodilator radionuclide imaging. Overall, 21.8% had ischemia. Patients with ischemia were more likely to be male, have CAD, heart failure, and diabetes (Table 1). The primary outcome occurred in 17.2%, and 6.7% had an elevated troponin. Ischemia was not associated with the primary (20.7% v. 16.2%, p=0.22) or secondary outcome (8.7% v. 6.1%, p=0.27). On multivariable analysis, a higher RCRI score and an inability to exercise were associated with the primary outcome while only RCRI was associated with the secondary outcome (Figure 1).ConclusionsIn patients undergoing vascular surgery, stress-induced ischemia did not provide risk stratification for cardiac events. Ischemia was also not associated with elevated troponin, supporting the hypothesis that post-operative troponinemia is often not mediated by severe epicardial stenosis. Table 1. Baseline Characteristics Figure 1. Multivariable logistic regression models