The prognostic value of right ventricular strain and mechanical dispersion on mortality in patients with normal left ventricle function

Aims: We aimed to assess if right ventricular (RV) 4-chamber longitudinal strain (RV4CLS), RV free wall longitudinal strain (RVFWLS) and RV mechanical dispersion index (RVMDI) have prognostic independent value in patients with preserved ejection fraction (pEF), without clearly elevated LV filling pressure. Methods: Retrospective analysis of Peak RV4CLS, RVFWLS, RVMDI and comprehensive echocardiographic assessment including left ventricle (LV), atrium (LA) strain and RV parameters in patients with pEF (EF ≥ 50%; E/e’ < 14). Multivariate Cox regression hazards model were used to determine the independent association between RV strain parameters to all-cause mortality and cardiovascular events. Results: We analyzed 224 consecutive patients with pEF (age 65.2 ± 19.8, 44% female, Charlson Comorbidity Index median = 3.8), with all-cause mortality of 64 patients and 28 cardiovascular events, during a median follow-up of 8.2 years (interquartile range: 6.8 to 8.4 years). The best strain univariate predictors of mortality were RV4CSL [1.16 (1.07–1.26); p = 0.0001] and RVMDI [1.01 (1.001–1.02); p = 0.02] being superior to LV and LA strain, or other RV functional indices. Moreover, after adjustment for clinical (age, gender, Charlson Comorbidity Index), conventional echocardiographic parameters (LA volume, E/e’ average, LVEDD, routine RV functional indices), LV and LA STE, RV4CLS and RVFWLS remained statistically significant associates of all-cause mortality and cardiac events. RV4CLS, or RVFWLS remained statistically significant associated for all-cause mortality, after additional adjustment for RVFAC and RVMDI. Conclusions: RV4CSL and RVMDI provide significant prognostic additive value in patients with preserved ejection fraction with excellent reproducibility, incremental to routine clinical, hemodynamic and LV and LA STE parameters.