Prognostic significance and normal values of 2D strain to assess right ventricular systolic function in chronic heart failure

BACKGROUND: Normal values and the prognostic significance of right ventricle (RV)-2D strain in chronic heart failure (CHF) patients are unknown. METHODS AND RESULTS: Between 2005 and 2010, we prospectively enrolled 43 controls and 118 stable CHF patients. Standard echocardiographic variables, tricuspid annular plane systolic excursion, peak systolic velocity of tricuspid annular motion using tissue Doppler imaging, and RV and left ventricle (LV) 2D-strain were measured. The primary outcome was death or emergency transplantation or emergency ventricular assist device implantation or acute heart failure. RV-2D strain was measurable in 39 controls (58±17 years, 50% men), whose median value was 30% (95% confidence interval [95%CI], 39%; 20%); and in 104 CHF patients (80% men, mean age 57±11 years, and mean LV ejection fraction 29%±8%), whose median value was 19% (95%CI, 34%; 9%). During the mean follow-up of 37±14 months, 44 experienced the primary outcome. By Cox proportional hazards multivariate analysis, only RV-2D strain and log B-type natriuretic peptide independently predicted experiencing the primary outcome within the first year. The best RV-2D strain cut-off by receiver-operating characteristics analysis was 21%, and patients with values >21% were at greatest risk (χ(2)-log-rank test=14.1, P