Vascular expansion during worsening of heart failure: Effects on clinical features and its determinants.

Background: This study investigated the relation of the changes in serum solutes/albumin to the level of vascular expansion and clinical features during worsening HF.

Methods: Data from 47 patients with acute on chronic HF worsening were analyzed. Blood tests included hemoglobin, hematocrit, albumin, solutes (Na/K/Cl/BUN/Cr), and b-type natriuretic peptide (BNP). The relative change in the vascular expansion from stable to worsening HF was estimated based on changes in the plasma volume (%PV).

Results: When divided into two groups based on the median %PV, the clinical features of the expansion group (11≤%PV [range 11% to 36%]; n=24) included a lower incidence of crackles (13% vs. 52%, p=0.005) and a tendency toward preserved renal function (83% vs. 57%, p=0.06) compared with the non-expansion group (%PV [range -19% to 11%]<11; n=23), whereas the increase in body weight and log BNP did not differ between groups. The expansion group had a greater increase in serum Na (3.58±4.43 vs. -0.11±3.31mEq/L, p=0.0016) and Cl (5.54±6.24 vs. -0.03±4.18mEq/L, p=0.0006), and a decrease in serum albumin (-0.37±0.3 vs. -0.16±0.3g/dL, p=0.04) and creatinine (-0.28±0.39 vs. -0.06±0.22mg/dL, p=0.027) from stability to worsening HF. Multivariate logistic regression analysis revealed an independent association between the increase in %PV and the increase in the serum Cl concentration from stability to worsening HF (odds ratio: 12.2, 95% confidence interval: 1.78-83.8, p=0.011).

Conclusions: Though this study is observational and does not allow for causal inference, it may nonetheless be speculated that a greater accumulation of Cl in the blood vessels acts to increase or maintain intravascular volume, which induces different clinical features of HF.