Abstract 11309: Significance of Blood Pressure Drops in Patients Hospitalized for Acute Heart Failure: A Patient-Level Analysis of 4 Randomized Placebo-Controlled Serelaxin Trials

Introduction: Hypotensive events and drops in systolic blood pressure (SBP-drop) are frequent in patients with acute heart failure (AHF). We investigated SBP-drop and associations with outcomes and whether treatment with the vasodilator serelaxin affected the association between SBP-drops and outcomes. Methods: Analyses of data from four randomized, controlled trials investigating serelaxin as an intervention in patients hospitalized with AHF. Main inclusion criteria were SBP 125-180 mmHg, pulmonary congestion, elevated NT-proBNP. SBP-drops (predefined as an SBP-value below 100 mmHg and/or a drop of 40 mmHg from baseline) were prospectively registered during the first 48 hours of hospitalization. Outcomes were a composite outcome (worsening heart failure, hospital readmission for heart failure or all-cause mortality through 14 days) and 180-day mortality. Results: Overall, 2558/11226 (23%) patients had an SBP-drop, with a median time from randomization to event of 15 (6-25) hours. In multivariable analyses, SBP-drop was associated with 180-day mortality (hazard ratio 1.21, 95% CI 1.05-1.39; p=0.009) and the composite outcome (1.29 (1.13-1.49); p<0.001). Treatment-allocation interacted significantly on the relationship between SBP-drops and outcomes (p-interaction=0.003 for composite outcome, p-interaction=0.11 for 180-day mortality). In patients treated with placebo (n=5141), there was a strong association between SBP-drops and the composite outcome (HR: 1.46, 95% CI 1.19-1.79), p=0.0003), but no significant association in patients treated with serelaxin (HR 1.18, 95% CI 0.97-1.42, p=0.10) (Figure). Conclusions: SBP-drops in hospitalized patients treated for AHF is an independent risk factor for adverse short- and long-term outcomes, and its occurrence highlights the need for careful monitoring and urgent treatment. However, in patients treated with serelaxin under careful observation, SBP-drops were not associated with worse outcome.