The significance of post-stress decrease in left ventricular ejection fraction in patients undergoing regadenoson stress gated SPECT myocardial perfusion imaging

Abstract

The significance of post-stress decrease in left ventricular ejection fraction (LVEF) with regadenoson stress gated SPECT (GSPECT) myocardial perfusion imaging (MPI) has not been studied. Consecutive patients who underwent rest/regadenoson stress GSPECT-MPI followed by coronary angiography within 6 months were analyzed. Change in LVEF by GSPECT-MPI was calculated as stress LVEF minus rest LVEF; a significant decrease was tested at 5% and 10% thresholds. In a diagnostic cohort of 793 subjects, LVEF change was not predictive of severe/extensive coronary artery disease (area under the curve, 0.50; 95% confidence interval, 0.44-0.57; P=0.946). There was no significant difference in the rates of severe/extensive coronary artery disease in patients with or without a decrease in LVEF, irrespective of MPI findings. In an outcome cohort of the 929 subjects followed for 30 ± 16 months, post-regadenoson stress decrease in LVEF was not associated with increased risk of the composite endpoint of cardiac death or myocardial infarction or in the risk of coronary revascularization. In patients selected to undergo coronary angiography following regadenoson stress GSPECT-MPI, a decrease in LVEF after regadenoson stress is not predictive of severe/extensive CAD or adverse clinical outcomes, irrespective of MPI findings.