Predictive value of phase analysis of gated myocardial perfusion imaging for major adverse cardiac events in patients with coronary artery disease

Abstract

Objective To evaluate the value of phase analysis of gated myocardial perfusion imaging (GMPI) in predicting major adverse cardiac events (MACE) in patients with coronary atherosclerotic heart disease. Methods Patients who underwent two-day rest-stress GMPI in the Department of Nuclear Medicine of Beijing Hospital from September 2012 to January 2014 were selected as observed subjects and analyzed retrospectively. The general clinical information, GMPI images and related parameters including phase standard deviation (PSD), phase histogram bandwidth (PBW), entropy, left ventricular ejection fraction (LVEF), summed stress score (SSS), peak ejection rate (PER), peak filling rate (PFR) were noted. Patients were followed up until the onset of MACE (cardiac death, nonfatal myocardial infarction, and late revascularization within 60 d after GMPI). χ2 test, independent-sample t test or Wilcoxon rank sum test were used to compare data between different groups. The independent risk factors of MACE were obtained by Cox proportional risk regression model. Kaplan-Meier survival curve analysis was used to analyze the cumulative survival rate without MACE. Results A total of 505 patients (235 males, 270 females, median age: 73 years) were followed up successfully, with a median follow-up period of 55.6(52.0, 60.5) months. There were 54 cases (10.7%) with MACE: 6 patients with cardiac death, 27 patients with non-fatal myocardial infarction, and 21 patients with late revascularization. The incidence of hypertension and hyperlipidemia in patients with MACE was significantly higher than that in patients without MACE (χ2 values: 4.126, 6.021, both P 80°), abnormal entropy(>58 J·mol-1·K-1) and SSS≥12 were independent risk factors for MACE (odds ratio(OR) values: 2.795(95% CI: 1.259-6.201), 3.213(95% CI: 1.468-7.029), 3.640 (95% CI: 1.999-6.628), all P 26.7°), abnormal PBW group and abnormal entropy group were 51.2%, 63.2% and 46.7%, which were significantly lower than those of normal PSD group (92.3%; χ2=77.768, P<0.05), normal PBW group (94.2%; χ2=77.741, P<0.05) and normal entropy group (92.8%; χ2=117.437, P<0.05). The 5-year cumulative MACE-free survival rate (31.7%) of patients with abnormal PBW and SSS≥12 was significantly lower than that of patients with normal PBW or patients with abnormal PBW and SSS<12 (80.1%-94.4%; χ2=185.4, P<0.01). The combination analysis of entropy and SSS showed similar results. Conclusions PBW and entropy obtained by GMPI phase analysis are independent risk factors for predicting MACE in coronary artery disease. GMPI phase analysis is useful for coronary artery disease risk stratification. Key words: Coronary artery disease; Prognosis; Myocardial perfusion imaging; Tomography, emission-computed, single-photon; Tomography, X-ray computed; Technetium Tc 99m sestamibi