Abstract
AIMS: Plasma volume status (PVS), a measure of plasma volume, has been evaluated as a prognostic marker for chronic heart failure. Although the prognostic value of PVS has been reported, its significance in patients with acute decompensated heart failure (ADHF) admitted to the cardiovascular intensive care unit (CICU) remains unclear. In this study, we examined the relationship between PVS and long-term mortality in patients with ADHF admitted to the CICU. METHODS: Between January 2018 and December 2020, 363 consecutive patients with ADHF were admitted to the Nippon Medical School Hospital CICU. Of the 363 patients, 206 (mean age, 74.9 ± 12.9 years; men, 64.6%) were enrolled in this study. Patients who received red blood cell transfusions, underwent dialysis, were discharged from the CICU or died in the hospital were excluded from the study. We measured the PVS of the patients at admission, transfer to the general ward (GW) and discharge using the Kaplan-Hakim formula. The patients were assigned to four groups according to the quartiles of their PVS measured at each of the three abovementioned timepoints. We examined the association between PVS and all-cause mortality during the observation period (1134 days). The primary endpoint of this study was all-cause mortality. RESULTS: The Kaplan-Meier analysis showed that the high PVS group had a significantly higher mortality rate at admission, transfer to the GW and discharge than the other groups (log-rank test: P = 0.016, P = 0.005 and P < 0.001, respectively). Univariate Cox regression analysis showed that age, body mass index, history of heart failure, use of beta-blockers, albumin level, blood urea nitrogen level, N-terminal pro-brain natriuretic peptide level and left ventricular ejection fraction were significantly different among the PVS groups and thus were not significant prognostic factors for ADHF. Furthermore, the multivariate analysis revealed that PVS at discharge [hazard ratio (HR) = 1.06 (1.00-1.12), P = 0.048] was an independent poor prognostic factor for ADHF. CONCLUSIONS: This study highlights the effect of PVS measured at different timepoints on the prognoses of ADHF patients. Regular assessment of PVS, particularly at discharge, is crucial for optimising patient management and achieving favourable outcomes in cases of ADHF.