IntroductionThe risk of unfavourable outcomes after an acute heart failure (AHF) episode remains high. Effective decongestion, reflected by haemoconcentration (HC), may guide therapy. Optimal timing of HC remains unspecified.MethodsWe analysed the AHF registry to evaluate the prognostic differences of various timing of HC. Subjects were divided into 3 groups by time of reaching HC.ResultsThe groups differed in terms of 1-year occurrence of a composite of the mortality and AHF hospitalization (26% vs. 46% vs. 40%, early vs. late vs. no HC, p = 0.016).ConclusionsPatients reaching HC earlier seem to present the best prognosis regarding the analysed composite endpoint.