The Incremental Prognostic Value of the Incorporation of Myocardial Perfusion Assessment into Clinical Testing with Stress Echocardiography Study

Background The authors recently demonstrated that simultaneous assessment of myocardial perfusion (MP) and wall motion (WM) by myocardial contrast echocardiography (MCE) is feasible and accurate when incorporated into a clinical stress echocardiography (SE) service. However, it is unknown whether the incremental prognostic value of MP beyond WM, previously shown in research studies, is reproducible when MCE is performed in the clinical arena. Methods In this prospective study, MCE was performed by multiple operators during routine clinical SE, whose results were classified as normal WM and MP, abnormal WM and MP, or normal WM but abnormal MP. Patients were followed for the prospectively determined combined primary outcome of all-cause mortality, nonfatal myocardial infarction, and late revascularization. Cox regression analyses were performed to identify predictors of outcome. Results Of 220 patients undergoing simultaneous MCE during SE, 197 patients (90%) with interpretable WM and MP images were available for follow-up at a mean time period of 17 ± 7 months. There were 35 events (six deaths, six myocardial infarctions, and 23 revascularizations). Among prognostic clinical variables, resting left ventricular function, and WM and MP data, abnormal MP at peak stress was the only independent predictor of primary outcome (hazard ratio, 4.41; 95% confidence interval, 1.37–14.20; P = .02). Sequential Cox regression models showed that abnormal MP also carried incremental prognostic value over clinical variables, resting left ventricular function and abnormal WM. Conclusions In keeping with previous research studies, this prospective study demonstrates the incremental prognostic benefit of MP assessment beyond WM when MCE is incorporated into a clinical SE service.