Predictors of moderate to severe ischemia among patients referred to stress myocardial perfusion scintigraphy

Introduction Patients with moderate to severe ischemia on stress myocardial perfusion scintigraphy are at highest risk for cardiovascular adverse events and death. The presence, extent and severity of ischemia detected on myocardial perfusion scintigraphy have all decreased over the past few years. Therefore, there is an increasing need to identify patient cohorts where the results of myocardial perfusion scintigraphy will have the greatest impact on clinical management. The data on predictors of moderate to severe ischemia within contemporary population of patients are scarce. Purpose of our study was to evaluate the predictors of moderate to severe ischemia across all potentially relevant clinical parameters in a cohort of patients referred to stress myocardial perfusion scintigraphy. Methods The clinical data and myocardial perfusion scintigraphy results of 4620 consecutive patients admitted to our department from January 2020 to December 2023 were prospectively collected. All patients underwent a 2-day stress/rest 99mTc tetrofosmin (Myoview, GE Healthcare) myocardial perfusion scintigraphy. Patients were imaged in the sitting position using a Cardius® X-ACT camera (Digirad, California, USA). The magnitude of myocardial ischemia was determined semi quantitatively in a 17-segment model according to the European Association of Nuclear Medicine guidelines. Patients were categorized in moderate to severe ischemia (>10% ischemia) and <10% of ischemia groups. Results The baseline clinical characteristics of the study population according to the degree of ischemia are shown in Table 1. Of the 4620 patients, 1695 (36.7%) had ischemia, 191 (4.1% of all patients, 11% of patients with ischemia) had moderate to severe ischemia. The proportion of male gender and the frequency of diabetes, dyslipidemia and prior coronary artery disease were higher in patients with moderate to severe ischemia (all p <0.001, Table 1). Patients with moderate to severe ischemia had more often typical chest pain, were inpatients and had a higher frequency of myocardial scar (all p <0.001, Table 1). In multivariable analysis male gender, diabetes, typical chest pain, known coronary artery disease and inpatient status turned out as predictors of moderate to severe ischemia (Table 2). Dyslipidemia and myocardial scar were not significant predictors (Table 2). Conclusion The prevalence of moderate to severe ischemia is particularly high among diabetic male patients with typical chest pain and known coronary artery disease. These observations may be used in clinical practice to identify patients who are most likely to benefit from referral to stress myocardial perfusion scintigraphy.