Clinical Significance of Global Wasted Work in patients receiving Cardiac Resynchronization Therapy for Heart Failure

Introduction Risk stratification remains key in the management of patients with heart failure (HF). Besides enduring standards such as left ventricular (LV) ejection fraction, the amount of LV myocardial global wasted work (GWW) might better predict outcome in HF patients who are eligible for cardiac resynchronization therapy (CRT). The aim of this study is to evaluate the relation between preoperative GWW and outcome in a large prospective cohort of patients with heart failure and reduced ejection fraction (HFrEF) receiving CRT. Method The study included 249 HF patients. GWW was calculated by speckle tracking strain two-dimensional echocardiography using pressure-strain loops. The primary outcome of the study was all-cause death. A combined response to CRT defined as LV reverse remodeling and/or absence of hospitalization for HF was also studied. Results Median follow-up was 48 months (interquartile range 43-54). Median preoperative GWW was 281 (184-388) mmHg%. Preoperative GWW correlated with mortality during follow-up (hazard ratio (HR) 1.5 (1.1-2.0) per SD decrement, P = 0.006). After adjustment on established predictors of outcome in HFrEF patients receiving CRT, patients with GWW  Fig. 1 ). Conclusion A low preoperative GWW (