Myocardial Perfusion Reserve After a PET-Driven Revascularization Procedure:A Strong Prognostic Factor

Not all patients treated on the basis of PET-proven viability benefit from revascularization. Myocardial perfusion reserve (MPR) predicts survival in patients not undergoing revascularization. In the present study, we investigated whether MPR is related to survival in ischemic heart disease (IHD) patients after a PET-driven intervention. Methods: Between 1995 and 2003, 119 consecutive patients with chronic IHD underwent a PET-driven revascularization procedure based on ischemia-viability assessment with PET. Patients were followed for all-cause mortality and major cardiovascular events. Results: One hundred nineteen patients underwent a PET-driven revascularization procedure (67 percutaneous coronary interventions, 52 coronary artery bypass grafts) because of angina complaints. The mean age was 67 +/- 11 y (96 men, 23 women); global left ventricle MPR was 1.54 +/- 0.43. MPR intertertile boundaries were 1.34 and 1.67. Significantly more cardiac deaths were observed in the lowest and middle MPR tertiles than in the highest tertile. The age-and sex-corrected hazard ratio for the middle tertile was 8.3 (95% confidence interval, 1.02-68.3) and for the lowest tertile 23.6 (95% confidence interval, 3.1-179) (P = 0.002). After left ventricular ejection fraction (LVEF) and viability were added to the model, MPR remained significant, with hazard ratios of 6.5 (0.8-54.4) and 18.5 (2.3-145.5) (P = 0.004), whereas neither LVEF nor viability reached significance in this model. Comparable results were found for major adverse cardiac events, with hazard ratios of 3.15 (0.82-12.0) and 8.24 (2.36-28.8) (P = 0.002). Conclusion: Patients with IHD revascularized on the basis of PET viability assessment who have a low MPR are at risk for cardiac death and subsequent cardiac events. MPR is a more sensitive predictor for cardiac death than LVEF and extent of viability.