End-Systolic Elastance and Ventricular-Arterial Coupling Reserve Predict Cardiac Events in Patients with Negative Stress Echocardiography

Background. A maximal negative stress echo identifies a low-risk subset for coronary events. However, the potentially prognostically relevant information on cardiovascular hemodynamics for heart-failure-related events is unsettled. Aim of this study was to assess the prognostic value of stress-induced variation in cardiovascular hemodynamics in patients with negative stress echocardiography. Methods. We enrolled 891 patients (593 males mean age 63 +/- 12, ejection fraction 48 +/- 17%), with negative (exercise 172, dipyridamole 482, and dobutamine 237) stress echocardiography result. During stress we assessed left ventricular end-systolic elastance index (ELVI), ventricular arterial coupling (VAC) indexed by the ratio of the ELVI to arterial elastance index (EaI), systemic vascular resistance (SVR), and pressure-volume area (PVA). Changes from rest to peak stress (reserve) were tested as predictors of main outcome measures: combined death and heart failure hospitalization. Results. During a median followup of 19 months (interquartile range 8-36), 50 deaths and 84 hospitalization occurred. Receiver-operating-characteristic curves identified as best predictors ELVI reserve for exercise (AUC = 0.871) and dobutamine (AUC = 0.848) and VAC reserve (AUC = 0.696) for dipyridamole. Conclusions. Patients with negative stress echocardiography may experience an adverse outcome, which can be identified by assessment of ELVI reserve and VAC reserve during stress echo.