Rest myocardial perfusion imaging: a valuable tool in ED

BackgroundAcute chest pain is a frequent cause of emergency department (ED) visits. Rest myocardial perfusion imaging (RMPI) during or immediately after an episode of chest pain can provide diagnostic and prognostic information concerning acute coronary syndromes.AimOur purpose was to evaluate the RMPI score in risk stratification of chest pain suspected to be of cardiac ischemic origin and negative troponin assessment.MethodsNinety-six patients without an ongoing myocardial infarction or a history of coronary artery disease and in whom RMPI was performed in the ED because of chest pain suspected to be related with acute myocardial ischemia were included.Follow-up was performed considering the occurrence of death, myocardial infarction, or revascularization in a 12-month period admission.ResultsFourteen (14.6%) patients had events. According to survival analysis, the variables related with events were a history of angina (hazard ratio [HR], 4.5; P ≤ .01), an ischemic electrocardiogram (HR, 4.0; P ≤ .01), the abnormal RMPI (HR, 11.4; P ≤ .05), and the RMPI score (HR, 1.1; P ≤ .0001). When the variables of interest were forced into a multivariate model, the χ2 associated with the model that includes clinical and electrocardiogram information was 16.3 (P ≤ .005) and in the model that also includes RMPI score, it was 23.0 (P ≤ .0005).ConclusionIn a low- to intermediate-risk group of patients with suspected acute myocardial ischemia, RMPI gives not only diagnostic information but adds prognostic value to the traditional ED risk stratification tools.