Abstract Aims STRONG-HF showed that rapid up-titration of guideline-recommended medical therapy (GRMT), in a high intensity care (HIC) strategy, was associated with better outcomes compared with usual care. The aim of this study was to assess the role of N-terminal pro-B-type natriuretic peptide (NT-proBNP) at baseline and its changes early during up-titration. Methods and results A total of 1077 patients hospitalized for acute heart failure (HF) and with a >10% NT-proBNP decrease from screening (i.e. admission) to randomization (i.e. pre-discharge), were included. Patients in HIC were stratified by further NT-proBNP changes, from randomization to 1 week later, as decreased (≥30%), stable (<30% decrease to ≤10% increase), or increased (>10%). The primary endpoint was 180-day HF readmission or death. The effect of HIC vs. usual care was independent of baseline NT-proBNP. Patients in the HIC group with stable or increased NT-proBNP were older, with more severe acute HF and worse renal and liver function. Per protocol, patients with increased NT-proBNP received more diuretics and were up-titrated more slowly during the first weeks after discharge. However, by 6 months, they reached 70.4% optimal GRMT doses, compared with 80.3% for those with NT-proBNP decrease. As a result, the primary endpoint at 60 and 90 days occurred in 8.3% and 11.1% of patients with increased NT-proBNP vs. 2.2% and 4.0% in those with decreased NT-proBNP (P = 0.039 and P = 0.045, respectively). However, no difference in outcome was found at 180 days (13.5% vs. 13.2%; P = 0.93). Conclusion Among patients with acute HF enrolled in STRONG-HF, HIC reduced 180-day HF readmission or death regardless of baseline NT-proBNP. GRMT up-titration early post-discharge, utilizing increased NT-proBNP as guidance to increase diuretic therapy and reduce the GRMT up-titration rate, resulted in the same 180-day outcomes regardless of early post-discharge NT-proBNP change.