Association of right ventricular dysfunction with blood volume expansion to outcomes in chronic left-sided heart...

The clinical significance of right ventricular dysfunction (RVD) and concomitant blood volume expansion (BVE) in chronic left-sided heart failure (HF) is not well characterized. Accordingly, we assessed the relationship of RVD severity to quantitative measures of blood volume (BV) on clinical outcomes. BV was measured in 150 clinically euvolemic patients at hospital discharge using nuclear medicine indicator-dilution methodology. Patients were stratified by severity of RVD and BVE ≥+25% of normal volume. Data were analyzed for the association of RVD and BVE to composite outcome (HF-related mortality/1st rehospitalization) at 1-year postindex hospitalization. Absolute BV was larger in patients with ≥ moderate RVD (n = 80) compared with normal right ventricle (RV) function (n = 36) (6.8 ± 1.6 vs. 6.1 ± 1.5 L, P = 0.029). Distribution of BV profiles within the two subgroups, however, varied significantly. BVE was demonstrated in 59% of patients with RVD [compared to 33% with normal RV (P = 0.010)] and normal BV in 25% with RVD {compared to 44% with normal RV (0.042)]. Kaplan-Meier and Cox regression analyses support BVE with erythrocythemia (relative to normal) as an independent predictors of better composite outcomes (P = 0.037), whereas RVD was not associated with an additional increase in risk (P = 0.137). This prospective analysis demonstrated a high prevalence of RVD (76% of cohort) and BVE (51%) at hospital discharge. Importantly, BVE with erythrocythemia was associated with better composite outcomes despite a high prevalence of RVD, whereas RVD alone was not a predictor of further risk. This suggests that BVE may serve as an adaptive response in part compensating RVD in chronic left-sided HF.NEW & NOTEWORTHY This analysis provides a novel assessment of the relationship between the severity of right ventricular dysfunction (RVD) and blood volume expansion (BVE) on clinical outcomes in patients with chronic left-sided heart failure. Findings demonstrate that despite the high prevalence of moderate or greater RVD, persistent BVE was associated with better 1-year event-free survival relative to normal BV. Hypothesis-generating, this suggests that BVE may provide an adaptive response compensating in part for the impact of RVD in chronic HF.