Effects of Metolazone Administration on Congestion, Diuretic Response and Renal Function in Patients with Advanced Heart Failure

Background: Advanced heart failure (HF) is a condition often requiring elevated doses of loop diuretics. Therefore, these patients often experience poor diuretic response. Both conditions have a detrimental impact on prognosis and hospitalization. Aims: This retrospective, multicenter study evaluates the effect of the addition of oral metolazone on diuretic response (DR), clinical congestion, NTproBNP values, and renal function over hospitalization phase. Follow-up analysis for a 6-month follow-up period was performed. Methods: We enrolled 132 patients with acute decompensated heart failure (ADHF) in advanced NYHA class with reduced ejection fraction (EF < 40%) taking a mean furosemide amount of 250 ± 120 mg/day. Sixty-five patients received traditional loop diuretic treatment plus metolazone (Group M). The mean dose ranged from 7.5 to 15 mg for one week. Sixty-seven patients continued the furosemide (Group F). Congestion score was evaluated according to the ESC recommendations. DR was assessed by the formula diuresis/40 mg of furosemide. Results: Patients in Group M and patients in Group F showed a similar prevalence of baseline clinical congestion (3.1 ± 0.7 in Group F vs. 3 ± 0.8 in Group M) and chronic kidney disease (CKD) (51% in Group M vs. 57% in Group F; p = 0.38). Patients in Group M experienced a better congestion score at discharge compared to patients in Group F (C score: 1 ± 1 in Group M vs. 3 ± 1 in Group F p > 0.05). Clinical congestion resolution was also associated with weight reduction (−6 ± 2 in Group M vs. −3 ± 1 kg in Group F, p < 0.05). Better DR response was observed in Group M compared to F (940 ± 149 mL/40 mgFUROSEMIDE/die vs. 541 ± 314 mL/40 mgFUROSEMIDE/die; p < 0.01), whereas median ΔNTproBNP remained similar between the two groups (−4819 ± 8718 in Group M vs. −3954 ± 5560 pg/mL in Group F NS). These data were associated with better daily diuresis during hospitalization in Group M (2820 ± 900 vs. 2050 ± 1120 mL p < 0.05). No differences were found in terms of WRF development and electrolyte unbalance at discharge, although Group M had a significant saline solution administration during hospitalization. Follow-up analysis did not differ between the group but a reduced trend for recurrent hospitalization was observed in the M group (26% vs. 38%). Conclusions: Metolazone administration could be helpful in patients taking an elevated loop diuretics dose. Use of thiazide therapy is associated with better decongestion and DR. Current findings could suggest positive insights due to the reduced amount of loop diuretics in patients with advanced HF.

Potential Role of Natriuretic Response to Furosemide Stress Test During Acute Heart Failure

Background: Poor natriuresis has been associated with a poorer response to diuretic treatment and worse prognosis in acute heart failure. Recommendations on how and when to measure urinary sodium (UNa) are lacking. We aim to evaluate UNa quantification after a furosemide stress test (FST) capacity to predict appropriate decongestion during acute heart failure hospitalization. Methods: Patients underwent an FST on day-1 of admission, and UNa was measured 2 hours after, dividing patients into low or high UNa based on the sample median value. A semiquantitative composite congestive score (CCS; 0–9) and NT pro-BNP (N-terminal pro-B-type natriuretic peptide) quantification were assessed before the FST and at day 5 after the FST. Results: Median UNa after FST in the 65 patients included was 113 (97–122) mmol/L. At day 5, a lower proportion of patients with a low UNa reached a 30% decrease in NT-proBNP levels (21 [66%] for low UNa versus 31 [94%] for high UNa; P =0.005) and an appropriate grade of decongestion (CCS<3) (20 [62%] for low UNa versus 32 [97%] for high UNa; P <0.001). A UNa>83 mmol/L 2 hours after FST had a 96% sensitivity to predict an NT-proBNP reduction ≥30% and 95% to predict a CCS<3 at day 5. Low UNa patients presented a lower cumulative diuresis and weight loss and presented more often with prolonged hospitalization, worsening heart failure, and readmission because of acute heart failure or death at 6 months. Conclusions: Low natriuresis after an FST identified patients at a higher risk of an inadequate diuretic response and an inappropriate decongestion. FST-guided diuretic treatment might help to improve decongestion, shorten hospitalizations, and to reduce adverse outcomes.

Syndecan-1 and Glypican-1 Knockout Alters Body Water Balance and Urine Response to Fluid Challenge in Mice

Syndecan-1 (Sdc-1) and glypican-1 (Gpc-1) are 2 important proteoglycans found in the glycocalyx and believed to govern transvascular distribution of fluid and protein. In this translational study, we assessed Sdc-1 and Gpc-1 knockout (KO) on whole body water balance after an intravenous volume challenge. Sdc-1 and Gpc-1 KO mice had higher starting blood water content versus strain-matched controls. Sdc-1 KO mice exhibited a significantly higher diuretic response (87%; <i>p</i> &#x3c; 0.05), higher excreted volume/infusion volume ratio (<i>p</i> &#x3c; 0.01), higher extravascular/infused ratio, and greater tissue water concentration (60 vs. 52%). Collectively, these suggest differences in kidney response and greater fluid efflux from peripheral vessels. The CD1 strain and Gpc-1 KO had a 2–3-fold larger urine output relative to C57 strain, but Gpc-1 KO reduced the excreted/infused ratio relative to controls (<i>p</i> &#x3c; 0.01) and they maintained plasma dilution longer. Thus, genetic KO of Sdc-1 and Gpc-1 resulted in markedly different phenotypes. This work establishes the feasibility of performing fluid balance studies in mice.

Congestion and Diuretic Resistance in Acute or Worsening Heart Failure

Hospitalisation for acute heart failure (AHF) is associated with high mortality and high rehospitalisation rates. In the absence of evidence-based therapy, treatment is aimed at stabilisation and symptom relief. The majority of AHF patients have signs and symptoms of fluid overload, and, therefore, decongestion is the number one treatment goal. Diuretics are the cornerstone of therapy in AHF, but the treatment effect is challenged by diuretic resistance and poor diuretic response throughout the spectrum of chronic to worsening to acute to post-worsening HF. Adequate dosing and monitoring and evaluation of diuretic effect are important for treatment success. Residual congestion at discharge is a strong predictor of worse outcomes. Therefore, achieving euvolaemia is crucial despite transient worsening renal function.

Comparing Diuresis Patterns in Hospitalized Patients With Heart Failure With Reduced Versus Preserved Ejection Fraction: A Retrospective Analysis

Background: Congestion predominates in exacerbations of heart failure with reduced ejection fraction (HFrEF) or preserved ejection fraction (HFpEF), but evidence suggests that excess volume may be distributed differently in these 2 subgroups. Methods and Results: In this retrospective study, diuretic efficiency (DE, or net urine output per 40-mg of intravenous furosemide equivalent) during the first 72 hours was compared between patients hospitalized with HFrEF (n = 121) versus HFpEF (n = 120). Multivariate analysis was used to compare the 2 groups based on expected baseline differences (e.g., demographics, heart failure etiology, concomitant therapy). During the first 72 hours, mean daily diuretic doses were higher in patients with HFpEF versus HFrEF (172.0 vs. 159.9 mg, respectively, p = 0.026) but urine output was not significantly different (2603.3 mL vs. 2667.5 mL, respectively, adjusted p = 0.100). Similarly, mean cumulative DE did not differ (−673.5 vs. −637.8 mL/40-mg in the HFrEF and HFpEF groups, respectively, adjusted p = 0.884). An exploratory analysis of propensity-matched cohorts yielded similar findings. Correlations between the components of DE varied considerably and only became weak to moderately correlated toward the end of the observation period. Conclusions: Although cumulative DE did not differ between patients with HFrEF and HFpEF, variable correlations in the components of DE suggest there may be differences in diuretic response that warrant future analysis.