SPC365

Optimal Initial Furosemide Dosing in Acute Heart Failure: Impact on Hospitalization and 1-Year Mortality

Session: SESSÃO DE POSTERS 30 - INSUFICIÊNCIA CARDÍACA CRÓNICA: TRATAMENTO
Speaker: João Reis Sabido

Congress: CPC 2025
Topic: D. Heart Failure
Theme: 11. Acute Heart Failure
Subtheme: 11.4 Acute Heart Failure– Treatment
Session Type: Cartazes
FP Number: ---
Authors: João Reis Sabido; Catarina Gregório; Diogo Ferreira; João Lucas Temtem; Daniel Inácio Cazeiro; Ana Abrantes; Miguel Azaredo Raposo; Joana Rigueira; Rafael Santos; Fausto J. Pinto; Dulce Brito; João R. Agostinho

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><strong>Introduction</strong></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">Despite the lack of prognostic impact, intravenous loop diuretic, mainly furosemide, is still the mainstay of acute heart failure (HF) treatment, being a widely used and effective choice to alleviate congestive symptoms. Paradoxically, there is no consensus regarding the best initial furosemide dose and its impact in the need for hospitalization or post-discharge mortality. This study aims to establish the best initial dose of furosemide to avoid hospitalization and to reduce post-discharge mortality. </span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><strong>Methods</strong></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">A retrospective analysis was performed including 186 consecutive patients, already on oral loop diuretics, admitted to the emergency department of a tertiary hospital between January and March of 2023 due to acute HF. The initial doses of loop diuretic (defined as the ratio between the intravenous dose and the patient&rsquo;s previous oral daily dose) used in patients that were hospitalized following the emergency department and in those discharged were compared. Receiver operating characteristic (ROC) curve was used to establish the best minimum relative dose of furosemide to avoid post-discharge mortality. Kaplan-Meier survival analysis was performed to assess whether treatment with a higher initial relative dose of furosemide had an association with 1-year survival.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><strong>Results</strong></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">Both the discharge and the hospitalization groups were similar in age, estimated glomerular filtration rate, NT-proBNP levels at initial evaluation and ambulatory dose of loop diuretic, the exception being the mean baseline left ventricular ejection fraction, which was lower in the discharged group (45.8% vs 52.2% respectively; p=0.027). </span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">In comparison to the hospitalization group, the discharged group was treated with a significantly higher first dose of furosemide (64.20 <em>vs</em> 40.31mg, p=0.01) and, consequently, a higher relative dose (1.54 <em>vs</em> 1.03, respectively; p=0.032). </span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">Using the ROC curve analysis, the lower relative furosemide dose to avoid post-discharge mortality was 1.416 (AUC: 0.632). To simplify, survival analysis was performed using a relative dose cut-off of 1.5 or higher, based on the previous findings. A significant decrease in 1-year mortality was observed in those treated with a higher initial relative dose (HR 2.4; 95% CI 1.054&ndash;5.683; p = 0.037) - Figure 1.</span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000"><strong>Discussion</strong></span></span></span></p>

<p style="text-align:justify"><span style="font-size:11pt"><span style="font-family:Calibri,sans-serif"><span style="color:#000000">Individuals presenting with acute HF who were hospitalized had a less aggressive initial diuretic strategy. A higher initial loop diuretic dose (at least 1.5 times the usual oral daily dose) was associated with a lower rate of hospitalization and post-discharge mortality in patients with acute heart failure. Adjustment of diuretic dose to each patient&rsquo;s usual dose could be used as a rule-of-thumb for choosing the initial strategy.</span></span></span></p>