Background: Characterization of ischemia is recommended in patients with stable coronary artery disease (CAD) prior to elective myocardial revascularization, ensuring appropriate indication where there is a reasonable expectation of benefit from the procedure. The aim of the present study was to evaluate the revascularization rate and the impact on mortality in patients referred to SPECT-MPI.

Methods: Medical records of the consecutive 14,185 patients’ cohort submitted to single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) from January 2007 to December 2010 at a single centre, were retrospectively analyzed. SPECT-MPI results were classified as abnormal on the presence of any perfusion defect. Abnormal scans were further classified as mild ischemia, moderate/severe ischemia, fibrosis and fibrosis and ischemia. Three year overall survival (3y-OS) analysis of group of patients with normal and abnormal scans, submitted or not to revascularization (percutaneous or surgical) was performed.

Results: Of the 14,185 patients, 1,320 (9.3%) died during mean follow up of 36 months (+/-12mo). 3y-OS of patients with normal scans, mild ischemia, fibrosis and ischemia, only fibrosis and moderate/severe ischemia were: 93.0%, 93.2%, 86.5, 85.3% and 82.5%, respectively (P<0.001). The overall revascularization incidence was 7.6%. The 3y-OS of patients with normal or with mild reversible defect SPECT-MPI that were or not further submitted to revascularization was similar (93.3% and 93.0% respectively); while in patients with moderate/severe ischemia on SPECT-MPI who were submitted to revascularization the 3y-OS was significantly lower than in those who did not underwent revascularization (90.4% and 87.5% respectively; P<0.001).

Conclusion: Significant differences were seen in the mortality rates comparing patients with normal and abnormal SPECT-MPI. Our findings suggest that patients with moderate or severe ischemic SPECT-MPI submitted to revascularization present lower mortality than those who were not revascularized. Also, revascularization does not have effect, prevent or impact on mortality in patients with normal SPECT-MPI or with mild defect.