Revascularization and outcomes in Veterans with moderate to severe ischemia on myocardial perfusion imaging

BACKGROUND: The prevalence of ischemia on nuclear myocardial perfusion imaging (MPI) has been decreasing. Recent research has questioned the benefit of invasive revascularization for patients with moderate to severe ischemia. We hypothesized that patients with moderate to severe ischemia could routinely undergo successful revascularization. METHODS: We analyzed data from 544 patients who underwent an MPI at a single academic Veterans Affairs Medical Center. Patients with moderate to severe ischemia, defined as a summed difference score (SDS) 8 or greater, were compared to the rest of the cohort. RESULTS: Of the total cohort (n = 544), 39 patients had MPI studies with resultant moderate to severe ischemia. Patients with ischemia were more likely to develop coronary artery disease (74.4% versus 38.8%, P < 0.0001) and have successful revascularization (38.5% versus 4.0%, P < 0.0001) during the following year. Revascularization was attempted in 31 patients with moderate to severe ischemia, though only 15 (47%) of these attempts were successful. Ischemia was predictive of myocardial infarction (5.1% versus 0.8%, P = 0.01) within 1 year. CONCLUSION: Moderate to severe ischemia is an uncommon finding in a contemporary nuclear laboratory. Among patients with ischemia, revascularization is typically attempted but is frequently unsuccessful. TRIAL REGISTRATION: This trial does not appear on a registry as it is neither randomized nor prospective.