Continuous Versus Intermittent Loop Diuretics Step-by-Step Protocol in Acute Heart Failure (DIUR-AHF): A Propensity-Matched Analysis

Background Loop diuretics are used to solve congestion in acute heart failure. However, a clear indication about the best infusion modality, dose, and duration of the treatment has not yet been established. In this analysis of the DIUR-AHF (Different Loop Diuretic Dosing and Administration in Acute Heart Failure) study, we aimed to investigate the effects of different diuretic administration modalities (ie, intermittent versus continuous furosemide infusion) and dose (high dose [HD] versus low dose) on congestion, renal function, and outcome. Methods Patients received intermittent or continuous intravenous loop diuretics infusion combined as a 1:1 ratio for a period of 72 to 120 hours. HD was defined as a high loop diuretic dose >120 mg/d. Clinical outcome was evaluated in terms of death or heart failure rehospitalization over a 6-month follow-up period. Results A total of 370 patients with AHF were included in this analysis, 189 treated with continuous intravenous loop diuretics infusion and 181 with intermittent intravenous loop diuretics infusion. At baseline, the continuous intravenous loop diuretic infusion group showed increased median values of blood urea (P=0.010) and creatinine (P=0.017). Dividing our sample according to loop diuretic dosage, the HD group revealed similar congestion and weight loss compared with the low-dose group; however, the HD group showed a reduced diuretic efficiency (-0.13 [-0.22 to -0.07] versus -0.32 [-0.59 to -0.20] kg/d; P<0.001) and an increased rate of adverse event occurrence (55% versus 20%; P<0.001). Multivariable analysis showed the association between HD treatment and poor postdischarge outcome (hazard ratio, 1.95 [95% CI, 1.23-3.10]; P=0.005). Conclusions An HD of loop diuretics infusion revealed an increased risk for adverse events together with reduced diuretic response. Our results extend previous findings revealing the association between HD diuretics and prognosis in patients with chronic HF. Additional studies may confer loop diuretic response in relation to the other decongestive treatments.