Abstract
BACKGROUND: Although randomized trials have provided evidence for invasive fractional flow reserve to guide revascularization, evidence for non-invasive imaging is less well established. The present study investigated whether hybrid coronary computed tomography (CCTA)/single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) can identify patients who benefit from early revascularization compared to medical therapy.
METHODS: This retrospective study consists of 414 patients referred for evaluation of known or suspected coronary artery disease (CAD) with CCTA/SPECT hybrid imaging. CCTA categorized patients into no CAD, non-high-risk CAD and high-risk CAD. In patients with CAD (n = 329), a matched finding (n = 75) was defined as a reversible perfusion defect in a territory subtended by a coronary artery with CAD. All other combinations of pathologic findings were classified as unmatched (n = 254). Death, myocardial infarction, unstable angina requiring hospitalization, and late coronary revascularization were defined as major adverse cardiac events (MACE). Cox hazards models included covariates age, male gender, more than two risk factors, previous CABG, high-risk CAD and early revascularization.
RESULTS: During median follow-up of 6.0 years, 112 patients experienced a MACE (27%). Early revascularization (n = 50) was independently associated with improved outcome among patients with a matched finding (p < 0.001). There was no benefit among patients with an unmatched finding (p = 0.787), irrespective of presence (p = 0.505) or absence of high-risk CAD (p = 0.631).
CONCLUSIONS: Early revascularization is associated with an outcome benefit in CAD patients with a matched finding documented by cardiac hybrid imaging while no benefit of revascularization was observed in patients with an unmatched finding.
Benz, Dominik C