Association of the extent of myocardial ischemia with outcomes in patients with suspected coronary artery disease in Japan: a cohort study

Abstract

Abstract Background There is an ongoing controversy regarding the necessity of single-photon emission computed tomography (SPECT) for patients with ischemic heart diseases after the publication of the results of the ISCHEMIA trial. Purpose We aimed to evaluate the association of the extent of myocardial ischemia with outcomes in patients with suspected coronary artery disease in Japan. Methods From the data of 2780 patients with stable angina who were enrolled prospectively between January 2006 and March 2008 in Japan and had undergone physician-referred non-invasive imaging tests, 1205 patients managed with SPECT were stratified by 10% myocardial ischemia. Major adverse cardiac events (MACEs), including death, myocardial infarction, hospitalization for heart failure, and late revascularization, were followed-up for 1 year. Results Patients with ≥10% myocardial ischemia (n=173) were older than patients with <10% myocardial ischemia (n=1032) and had a significantly higher 1-year cumulative incidence of MACEs (9.1% vs. 1.2%, P<0.0001). After adjusting for confounders, the risk of ≥10% myocardial ischemia relative to <10% myocardial ischemia for MACEs remained significant (adjusted hazard ratio [95% confidence interval], 2.40 [1.09–5.26], P=0.029). Conclusion The presence of ≥10% myocardial ischemia was significantly associated with the 1-year risk for MACEs in Japanese patients with suspected coronary artery disease. Funding Acknowledgement Type of funding sources: None. Study flowchartOutcomes