Ischemic myocardial perfusion is a strong predictor of death in women in Brazil

Objectives To assess the prognosis of contemporary single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI) in all-cause mortality for women in a developing country.

Methods A total of 2,225 consecutive women with mean age of 64.5 (± 5.6) years referred for SPECT-MPI were followed by a mean period of 3.7 ± 1.4 years. SPECT-MPI scan results were classified as abnormal on the presence of any perfusion defects. Abnormal scans were further classified as with mild/moderate reversible, severe reversible, fixed and mixed perfusion defects. Multivariable Cox proportional hazard models were developed to predict all-cause mortality. Risk-adjusted models incorporated clinical risk factors, left ventricular ejection fraction (LVEF) and perfusion variables.

Results All-cause death was observed in 139 patients and SPECT-MPI results significantly risk stratified the population; patients whose scans presented perfusion defect had significantly higher death rates compared to patients with normal scans, 13.1% vs 4.0%, respectively (P< 0.001). Cox proportional hazards analysis demonstrated that after adjusting for known ischemic heart disease (IHD), age, smoking status and LVEF, SPECT-MPI results added significant incremental prognostic information (global chi-square increased from 87.7 to 127.1; P <0.0001).

Conclusions SPECT-MPI added incremental prognostic information to clinical and left ventricular function variables for women in a developing country. Presence of severe reversible perfusion defects was the most powerful prognostic factor in prediction of all-cause death. Although the contemporary advances on IHD therapy, a higher mortality rate was observed in women with severely abnormal SPECT-MPI when compared to previous studies in developed countries