摘要:Background: Hemoconcentration (HC) has been suggested to be a useful biomarker for determination of optimum diuretic therapy in acute heart failure (HF), but role of this factor in rehospitalization and death was still controversial. In this study, we aimed to define relation between HC and readmission and mortality rate among Iranian patients with acute HF. Methods: This was a prospective cohort study done from March 2017 to March 2018 using data of a HF section of Persian Registry Of cardioVascular diseasE. From a total number of 390 registered HF individuals aged 18 years or older, 69 ones showed alterations in hemoglobin (Hb) levels. Hb levels were measured at admission and discharge time. HC was defined as any increased level in Hb during hospitalization. The relation of HC with readmission and death rate was done using multiple logistic regression and Cox proportional hazard model, respectively. Results: The mean age of study population was 70.5 ± 11.9 years with the dominant percentage of male participants (66.9%). Patients showing HC during admission did not reveal any significant decreased likelihood of rehospitalization compared to negative ones. In comparison to HC negative patients, those showing increments in Hb levels had a borderline significant lower likelihood of mortality (hazard ratio: 0.82, 95% confidence interval, CI = 0.07–1.18, P = 0.08). Conclusions: Our data suggested that HC was associated marginally with reduced mortality rate 6 months post HF attack and could be utilized as a useful biomarker for risk stratification of HF patients. Several prospective longitudinal population-based studies are necessary proving these associations.