Basal natriuresis as a predictor of diuretic resistance and clinical evolution in acute heart failure

BACKGROUND

Some clinical guidelines recommend serial measurement of natriuresis to detect diuretic resistance (DR) in acute heart failure (AHF) patients, but it adds complexity to the management.

OBJECTIVES

To correlate a single measurement of basal natriuresis (BN) on admission with the development of DR and clinical evolution in AHF hospitalized patients.

METHODS

Prospective and multicenter study included AHF hospitalized patients, without shock or creatinine >2.5mg%. Patients received 40mg of intravenous furosemide on admission, then BN was measured, and diuretic treatment was guided by protocol. BN was considered low if <70 meq/L. DR was defined as the need of furosemide >240mg/day, tubular blockade (TB), hypertonic saline solution (HSS) or renal replacement therapy (RRT). In-hospital cardiovascular (CV) mortality, CV mortality and AHF readmissions at 60-day post-discharge were evaluated.

RESULTS

157 patients were included. BN was low in 22%. DR was development in 19% (12.7% furosemide >240mg/day, 8% TB, 4% RRT). Low NB was associated with DR (44% vs 12%; p 0.0001), persistence of congestion (26.5% vs 11.4%; p 0.05), furosemide >240 mg/day (29% vs 8%; p 0.003), higher cumulative furosemide dose at 72 hours (220 vs 160mg; p 0.0001), TB (20.6 vs 4.9%; p 0.008), RRT (11.8 vs 1.6%; p 0.02), worsening of AHF (27% vs 9%; p 0.01), inotropes use (21% vs 7%; p 0.48), respiratory assistance (12% vs 2%; p 0.02) and a higher in-hospital CV mortality (12% vs 4%; p 0.1). No association was demonstrated with post-discharge endpoints.

CONCLUSIONS

In AHF patients, low BN was associated with DR, persistent congestion, need for aggressive decongestion strategies, and worse in-hospital evolution.

Treatment strategies for diuretic resistance in patients with heart failure

Improving congestion with diuretic therapy is crucial in the treatment of heart failure (HF). However, despite the use of loop diuretics, diuresis may be inadequate and congestion persists, which is known as diuretic resistance. Diuretic resistance and residual congestion are associated with a higher risk of rehospitalization and mortality. Causes of diuretic resistance in HF include diuretic pharmacokinetic changes, renal hemodynamic perturbations, neurohumoral activations, renal tubular remodeling, and use of nephrotoxic drugs as well as patient comorbidities. Combination diuretic therapy (CDT) has been advocated for the treatment of diuretic resistance. Thiazides, acetazolamides, tolvaptan, mineralocorticoid receptor antagonist, and sodium-glucose co-transporter-2 inhibitors are among the candidates, but none of these treatments has yet demonstrated significant diuretic efficacy or improved prognosis. At present, it is essential to identify and treat the causes of diuretic resistance in individual patients and to use CDT based on a better understanding of the characteristics of each drug to achieve adequate diuresis. Further research is needed to effectively assess and manage diuretic resistance and ultimately improve patient outcomes.

Association Between Serum Albumin and the Length of Hospital Stay Among Patients With Acute Heart Failure

Introduction: Albumin plays a vital role in improving osmotic pressure and hemodynamics. A lower serum albumin level may cause pulmonary congestion and edema and contribute to myocardial dysfunction, diuresis resistance, and fluid retention in acute heart failure. Hypothesis: We hypothesized that AHF patients with normal serum albumin have shorter hospital stays. Methods: Using Electronic Medical Records, patients admitted from May 2020 through May 2021 aged >18, ICD-10, and positive Framingham Heart Failure Diagnostic Criteria were included. We excluded patients without albumin records and eGFRs less than 30 mL/min/1.73 m2. Prolonged hospitalization was defined as >8 days of hospitalization. Results: During index emergency department visits, patients were symptomatic (New York Heart Association), aged median of 70 years (Interquartile range (IQR) 18), 59% (n = 103) were male, predominantly White (73%, n = 128), and had a high Charleston Comorbidity index score [5, IQR (4-7)]. Nearly one-fourth (23%, n = 41) of the patients had <3.5 g/dL albumin levels. The median length of hospital stay was eight days (IQR of 11). Comparing differences between lengths of hospital stays (<8 vs. >8 days), there was different serum albumin (3.9 + 0.48 vs. 3.6 + 0.53, p < .001) and left ventricular ejection fraction (45% (range 26-63) versus 30% (range 24-48), p = .004). An increased serum albumin decreased prolonged hospitalization (odds ratio (OR), 0.28; 95% confidence interval (CI), 0.14-0.55, p = <0.001). Patients in the lower albumin group had higher NT-proBNP (median: 8521 (range 2025-9134) versus 5147 (range 2966-14,795) pg/ml, p = .007) and delay in administering intravenous diuretics (391 (167-964) minutes versus 271 (range 157-533) minutes, p = .02). Conclusion: Hypoalbuminemia is strongly associated with prolonged hospitalization. Timely and effective diuretic therapy may reduce hospital stay durations, particularly with albumin supplementation.

Discovery of BMS-986308: A Renal Outer Medullary Potassium Channel Inhibitor for the Treatment of Heart Failure

Recent literature reports highlight the importance of the renal outer medullary potassium (ROMK) channel in renal sodium and potassium homeostasis and emphasize the potential impact that ROMK inhibitors could have as a novel mechanism diuretic in heart failure patients. A series of piperazine-based ROMK inhibitors were designed and optimized to achieve excellent ROMK potency, hERG selectivity, and ADME properties, which led to the identification of compound 28 (BMS-986308). BMS-986308 demonstrated efficacy in the volume-loaded rat diuresis model as well as promising in vitro and in vivo profiles and was therefore advanced to clinical development.

Urinary Cell Cycle Arrest Biomarkers and Diuretic Efficiency in Acute Heart Failure

INTRODUCTION

This study aimed to evaluate the association between the NephroCheck® test AKIRisk® score, diuretic efficiency (DE), and the odds of worsening kidney function (WKF) within the first 72 h of admission in patients hospitalized for acute heart failure (AHF).

METHODS

The study prospectively enrolled 125 patients admitted with AHF. NephroCheck® test was obtained within the first 24 h of admission. DE was defined as net fluid urine output per 40 mg of furosemide equivalents.

RESULTS

The median AKIRisk® score was 0.11 (IQR 0.06-0.34), and 38 (30.4%) patients had an AKIRisk® score >0.3. The median cumulative DE at 72 h was 1,963 mL (IQR 1317-3,239 mL). At 72 h, a total of 10 (8%) patients developed an absolute increase in sCr ≥0.5 mg/dL (WKF). In a multivariable setting, there was an inverse association between the AKIRisk® score and DE within the first 72 h. In fact, the highest the AKIRisk® score (centered at 0.3), the higher the likelihood of poor DE (below the median) and WKF at 72 h (odds ratio [OR] 2.04; 95%; CI: 1.02-4.07; p = 0.043, and OR 3.31, 95% CI: 1.30-8.43; p = 0.012, respectively).

CONCLUSION

In patients with AHF, a higher NephroCheck® AKIRisk® score is associated with poorer DE and a higher risk of WKF at 72 h. Further research is needed to confirm the role of urinary cell cycle arrest biomarkers in the AHF scenario.

Efficacy and Safety of Dapagliflozin in Patients With Acute Heart Failure

BACKGROUND

The primary goals during acute heart failure (AHF) hospitalization are decongestion and guideline-directed medical therapy (GDMT) optimization. Unlike diuretics or other GDMT, early dapagliflozin initiation could achieve both AHF goals.

OBJECTIVES

The authors aimed to assess the diuretic efficacy and safety of early dapagliflozin initiation in AHF.

METHODS

In a multicenter, open-label study, 240 patients were randomized within 24 hours of hospital presentation for hypervolemic AHF to dapagliflozin 10 mg once daily or structured usual care with protocolized diuretic titration until day 5 or hospital discharge. The primary outcome, diuretic efficiency expressed as cumulative weight change per cumulative loop diuretic dose, was compared across treatment assignment using a proportional odds model adjusted for baseline weight. Secondary and safety outcomes were adjudicated by a blinded committee.

RESULTS

For diuretic efficiency, there was no difference between dapagliflozin and usual care (OR: 0.65; 95% CI: 0.41-1.02; P = 0.06). Dapagliflozin was associated with reduced loop diuretic doses (560 mg [Q1-Q3: 260-1,150 mg] vs 800 mg [Q1-Q3: 380-1,715 mg]; P = 0.006) and fewer intravenous diuretic up-titrations (P ≤ 0.05) to achieve equivalent weight loss as usual care. Early dapagliflozin initiation did not increase diabetic, renal, or cardiovascular safety events. Dapagliflozin was associated with improved median 24-hour natriuresis (P = 0.03) and urine output (P = 0.005), expediting hospital discharge over the study period.

CONCLUSIONS

Early dapagliflozin during AHF hospitalization is safe and fulfills a component of GDMT optimization. Dapagliflozin was not associated with a statistically significant reduction in weight-based diuretic efficiency but was associated with evidence for enhanced diuresis among patients with AHF. (Efficacy and Safety of Dapagliflozin in Acute Heart Failure [DICTATE-AHF]; NCT04298229).

Acetazolamide as an Adjunctive Diuretic Therapy for Patients with Acute Decompensated Heart Failure: A Systematic Review and Meta-Analysis

BACKGROUND

Recent evidence suggests that acetazolamide may be beneficial as an adjunctive diuretic therapy in patients with acute decompensated heart failure (HF). We aim to pool all the studies conducted until now and provide updated evidence regarding the role of acetazolamide as adjunctive diuretic in patients with acute decompensated HF.

METHODS

PubMed/Medline, Cochrane Library, and Scopus were searched from inception until July 2023, for randomized and nonrandomized studies evaluating acetazolamide as add-on diuretic in patients with acute decompensated HF. Data about natriuresis, urine output, decongestion, and the clinical signs of congestion were extracted, pooled, and analyzed. Data were pooled using a random effects model. Results were presented as risk ratios (RRs), odds ratios (ORs), or weighted mean differences (WMD) with 95% confidence intervals (95% CIs). Certainty of evidence was assessed using the grading of recommendation, assessment, development, and evaluation (GRADE) approach. A P value of < 0.05 was considered significant in all cases.

RESULTS

A total of 5 studies (n = 684 patients) were included with a median follow-up time of 3 months. Pooled analysis demonstrated significantly increased natriuresis (MD 55.07, 95% CI 35.1-77.04, P < 0.00001; I2 = 54%; moderate certainty), urine output (MD 1.04, 95% CI 0.10-1.97, P = 0.03; I2 = 79%; moderate certainty) and decongestion [odds ratio (OR) 1.62, 95% CI 1.14-2.31, P = 0.007; I2 = 0%; high certainty] in the acetazolamide group, as compared with controls. There was no significant difference in ascites (RR 0.56, 95% CI 0.23-1.36, P = 0.20; I2 = 0%; low certainty), edema (RR 1.02, 95% CI 0.52-2.0, P = 0.95; I2 = 45%; very low certainty), raised jugular venous pressure (JVP) (RR 0.86, 95% CI 0.63-1.17, P = 0.35; I2 = 0%; low certainty), and pulmonary rales (RR 0.82, 95% CI 0.44-1.51, P = 0.52; I2 = 25%; low certainty) between the two groups.

CONCLUSIONS

Acetazolamide as an adjunctive diuretic significantly improves global surrogate endpoints for decongestion therapy but not all individual signs and symptoms of volume overload.

SYSTEMATIC REVIEW REGISTRATION

This systematic review was prospectively registered on the PROSPERO ( https://www.crd.york.ac.uk/PROSPERO/ ), registration number CRD498330.

A review of the contemporary use of inotropes in patients with heart failure

PURPOSE OF REVIEW

The role of inotropes has evolved with its use now expanding over multiple indications including cardiogenic shock, low cardiac output states, bridging therapy to transplant or mechanical support, and palliative care. There remains no consensus as to the recommended inotrope for the failing heart. We aim to provide an overview of the recent literature related to inotrope therapy and its application in patients with advanced heart failure and hemodynamic compromise.

RECENT FINDINGS

In this review, we outline various clinical scenarios that warrant the use of inotrope therapy and the associated recommendations. There remains no mortality benefit with inotrope use. Per American Heart Association recommendations, the choice of the inotropic agent should be guided by parameters such as blood pressure, concurrent arrhythmias, and availability of the medication. Outcome variability remains a heightened concern with inpatient inotropic use in both hemodynamically stable and unstable patients. Finally, inotropic use in palliative care continues to be a recommendation for symptom control and improvement in functional status when the appropriate social support is present for the patient.

SUMMARY

In summary, the ideal inotropic agent remains at the discretion of the clinical provider. Different clinical scenarios may favor one agent over another based on the type of cardiogenic shock and mechanism of action of the inotrope. A future shift towards characterizing inotrope use based on subgroup cardiogenic shock profiles may be seen, however further studies are needed to better understand these phenotypes. Inotrope therapy remains a keystone to bridging to advanced therapies and palliative care.

A Phenomapping Tool and Clinical Score to Identify Low Diuretic Efficiency in Acute Decompensated Heart Failure

BACKGROUND

Individuals with acute decompensated heart failure (ADHF) have a varying response to diuretic therapy. Strategies for the early identification of low diuretic efficiency to inform decongestion therapies are lacking.

OBJECTIVES

The authors sought to develop and externally validate a machine learning-based phenomapping approach and integer-based diuresis score to identify patients with low diuretic efficiency.

METHODS

Participants with ADHF from ROSE-AHF, CARRESS-HF, and ATHENA-HF were pooled in the derivation cohort (n = 794). Multivariable finite-mixture model-based phenomapping was performed to identify phenogroups based on diuretic efficiency (urine output over the first 72 hours per total intravenous furosemide equivalent loop diuretic dose). Phenogroups were externally validated in other pooled ADHF trials (DOSE/ESCAPE). An integer-based diuresis score (BAN-ADHF score: blood urea nitrogen, creatinine, natriuretic peptide levels, atrial fibrillation, diastolic blood pressure, hypertension and home diuretic, and heart failure hospitalization) was developed and validated based on predictors of the diuretic efficiency phenogroups to estimate the probability of low diuretic efficiency using the pooled ADHF trials described earlier. The associations of the BAN-ADHF score with markers and symptoms of congestion, length of stay, in-hospital mortality, and global well-being were assessed using adjusted regression models.

RESULTS

Clustering identified 3 phenogroups based on diuretic efficiency: phenogroup 1 (n = 370; 47%) had lower diuretic efficiency (median: 13.1 mL/mg; Q1-Q3: 7.7-19.4 mL/mg) than phenogroups 2 (n = 290; 37%) and 3 (n = 134; 17%) (median: 17.8 mL/mg; Q1-Q3: 10.8-26.1 mL/mg and median: 35.3 mL/mg; Q1-Q3: 17.5-49.0 mL/mg, respectively) (P < 0.001). The median urine output difference in response to 80 mg intravenous twice-daily furosemide between the lowest and highest diuretic efficiency group (phenogroup 1 vs 3) was 3,520 mL/d. The BAN-ADHF score demonstrated good model performance for predicting the lowest diuretic efficiency phenogroup membership (C-index: 0.92 in DOSE/ESCAPE validation cohort) that was superior to measures of kidney function (creatinine or blood urea nitrogen), natriuretic peptide levels, or home diuretic dose (DeLong P < 0.001 for all). Net urine output in response to 80 mg intravenous twice-daily furosemide among patients with a low vs high (5 vs 20) BAN-ADHF score was 2,650 vs 660 mL per 24 hours, respectively. Participants with higher BAN-ADHF scores had significantly lower global well-being, higher natriuretic peptide levels on discharge, a longer in-hospital stay, and a higher risk of in-hospital mortality in both derivation and validation cohorts.

CONCLUSIONS

The authors developed and validated a phenomapping strategy and diuresis score for individuals with ADHF and differential response to diuretic therapy, which was associated with length of stay and mortality.

Predictors of a Good Diuretic Response and Administration Methods for Carperitide in Patients With Acute Heart Failure

PURPOSE

In Japan, carperitide has been recommended for the treatment of pulmonary congestion in patients with acute heart failure. Identifying useful indicators to support the decision to administer carperitide and the optimal timing of administration may lead to better improvement of pulmonary congestion. Therefore, we investigated the factors associated with good diuretic response to carperitide in patients with acute heart failure and the optimal timing of carperitide administration.

METHODS

This retrospective cohort study investigated 293 hospitalized patients who were diagnosed with acute heart failure and treated with carperitide at the Department of Cardiology, Showa University Fujigaoka Hospital. The primary endpoint was the diuretic response to carperitide. Patients with urine output ≥100 mL/h were defined as the good diuretic response group, and those with a urine output <100 mL/h during the first 6 hours of carperitide administration were defined as the poor diuretic response group. Multivariate analysis was used to examine the predictors of good diuretic response. The relationship between the time from intravenous furosemide to carperitide administration and urine output was also investigated.

FINDINGS

The patients' median age was 77 (range: 28-99) years, and 75.5% had New York Heart Association stage IV acute heart failure. The median urine output within 6 hours of carperitide administration was 104.5 (range: 6.6-1571.3) mL/h, and 118 patients (53.6%) showed a good diuretic response. Significant predictors of good diuretic response were age < 75 years [odds ratio (OR) 4.186; 95% confidence interval (CI), 2.129-8.230; P < 0.001], no prior use of loop diuretics (OR 2.155; 95% CI, 1.104-4.207; P = 0.024), blood urea nitrogen <20 mg/dL (OR 2.637; 95% CI, 1.340-5.190; P = 0.005), and white blood cell count <8.6 × 109/L (OR 3.162; 95% CI, 1.628-6.140; P = 0.001). The median urine output in the group with <2 hours between intravenous furosemide and carperitide administration was significantly higher than that in the group with an interval >6 hours [127.3; interquartile range (IQR), 77.6-216.2 mL/h vs. 66.2; IQR. 51.8-114.8 mL/h; P = 0.012).

IMPLICATIONS

The 4 predictors (age, no prior use of loop diuretics, blood urea nitrogen, and white blood cell count) of good diuretic response are useful indicators to support decision-making for carperitide administration. Additionally, the administration of carperitide within 2 hours of intravenous furosemide may lead to the improvement of pulmonary congestion.

Impact of vasodilators on diuretic response in patients with congestive heart failure: A mechanistic trial of cimlanod (BMS-986231)

AIM

To investigate the effects of Cimlanod, a nitroxyl donor with vasodilator properties, on water and salt excretion after an administration of an intravenos bolus of furosemide.

METHODS AND RESULTS

In this randomized, double-blind, mechanistic, crossover trial, 21 patients with left ventricular ejection fraction <45%, increased plasma concentrations of N-terminal pro-B-type natriuretic peptide (NT-proBNP) and receiving loop diuretics were given, on separate study days, either an 8 h intravenous (IV) infusion of cimlanod (12 μg/kg/min) or placebo. Furosemide was given as a 40 mg IV bolus four hours after the start of infusion. The primary endpoint was urine volume in the 4 h after the bolus of furosemide during infusion of cimlanod compared with placebo. Median NT-proBNP at baseline was 1487 (interquartile range: 847-2665) ng/L. Infusion of cimlanod increased cardiac output and reduced blood pressure without affecting cardiac power index consistent with its vasodilator effects. Urine volume in the 4 h post-furosemide was lower with cimlanod (1032 ± 393 ml) versus placebo (1481 ± 560 ml) (p = 0.002), as were total sodium excretion (p = 0.004), fractional sodium excretion (p = 0.016), systolic blood pressure (p < 0.001), estimated glomerular filtration rate (p = 0.012), and haemoglobin (p = 0.010), an index of plasma volume expansion.

CONCLUSIONS

For patients with heart failure and congestion, vasodilatation with agents such as cimlanod reduces the response to diuretic agents, which may offset any benefit from acute reductions in cardiac preload and afterload.

Urine sodium concentration after intravenous furosemide in dogs with acute congestive heart failure and correlation with treatment efficacy

BACKGROUND

Poor natriuresis is a potential marker of diuretic resistance in dogs with acute congestive heart failure (CHF) but little is known about the relationship between urine sodium concentration (uNa) and frequency of successful decongestion. Supplemental O2 is a common treatment in dogs with severe CHF. The time from start to discontinuation of supplemental O2 therapy (DCSO2 ) typically reflects the time course and ease of decongestion.

HYPOTHESIS/OBJECTIVES

Urine Na concentration after IV administration of furosemide will be correlated with duration of treatment with supplemental O2 (timeO2 ) and the cumulative frequency of successful DCSO2 during hospitalization.

ANIMALS

Fifty-one dogs with acute CHF.

METHODS

Retrospective observational single center study.

RESULTS

Dogs with low uNa had significantly longer mean timeO2 than dogs with high uNa (uNa <87 mmol/L, 24.2 ± 2.6 hours vs uNa ≥87 mmol/L, 16.6 ± 1.7 hours; P = .02). Low uNa was correlated with lower cumulative frequency of DCSO2 (12 hour, 28%; 24 hour, 42%; 36 hour, 73%) compared to high uNa (12 hour, 28%; 24 hour, 88%; 36 hour, 96%; P = .005). History of PO loop diuretics, low serum chloride concentration (sCl), and high PCV were associated with low uNa. Urine Na concentration outperformed other metrics of diuretic responsiveness including weight loss.

CONCLUSIONS AND CLINICAL IMPORTANCE

Urine Na concentration after IV furosemide predicted timeO2 and cumulative frequency of DCSO2 in dogs with acute CHF, which likely reflects important aspects of diuretic responsiveness. Urine Na can assess diuretic responsiveness and treatment efficacy in dogs with CHF.

Protocolized Natriuresis-Guided Decongestion Improves Diuretic Response: The Multicenter ENACT-HF Study

BACKGROUND

The use of urinary sodium to guide diuretics in acute heart failure is recommended by experts and the most recent European Society of Cardiology guidelines. However, there are limited data to support this recommendation. The ENACT-HF study (Efficacy of a Standardized Diuretic Protocol in Acute Heart Failure) investigated the feasibility and efficacy of a standardized natriuresis-guided diuretic protocol in patients with acute heart failure and signs of volume overload.

METHODS

ENACT-HF was an international, multicenter, open-label, pragmatic, 2-phase study, comparing the current standard of care of each center with a standardized diuretic protocol, including urinary sodium to guide therapy. The primary end point was natriuresis after 1 day. Secondary end points included cumulative natriuresis and diuresis after 2 days of treatment, length of stay, and in-hospital mortality. All end points were adjusted for baseline differences between both treatment arms.

RESULTS

Four hundred one patients from 29 centers in 18 countries worldwide were included in the study. The natriuresis after 1 day was significantly higher in the protocol arm compared with the standard of care arm (282 versus 174 mmol; adjusted mean ratio, 1.64; P<0.001). After 2 days, the natriuresis remained higher in the protocol arm (538 versus 365 mmol; adjusted mean ratio, 1.52; P<0.001), with a significantly higher diuresis (5776 versus 4381 mL; adjusted mean ratio, 1.33; P<0.001). The protocol arm had a shorter length of stay (5.8 versus 7.0 days; adjusted mean ratio, 0.87; P=0.036). In-hospital mortality was low and did not significantly differ between the 2 arms (1.4% versus 2.0%; P=0.852).

CONCLUSIONS

A standardized natriuresis-guided diuretic protocol to guide decongestion in acute heart failure was feasible, safe, and resulted in higher natriuresis and diuresis, as well as a shorter length of stay.

The clinical outcomes of dapagliflozin in patients with acute heart failure: A randomized controlled trial (DAPA-RESPONSE-AHF)

AIMS

Dapagliflozin may confer additional decongestive and natriuretic benefits to patients with acute heart failure (AHF). Nonetheless, this hypothesis was not clinically examined. This study aimed primarily to investigate the effect of dapagliflozin on symptomatic relief in those patients.

METHODS

This was a randomized, double-blind study that included 87 patients with AHF presenting with dyspnea. Within 24 h of admission, patients were randomized to receive either dapagliflozin (10 mg/day, N = 45) or placebo (N = 42) for 30 days. The primary outcome was the difference between the two groups in the area under the curve (AUC) of visual analogue scale (VAS) dyspnea score over the first 4 days. Secondary endpoints included urinary sodium (Na) after 2 h of randomization, percent change in NT-proBNP, cumulative urine output (UOP), and differences in mortality and hospital readmission rates.

RESULTS

The results showed that dapagliflozin significantly reduced the AUC of VAS dyspnea score compared to placebo (3192.2 ± 1631.9 mm × h vs 4713.1 ± 1714.9 mm × h, P < 0.001). The relative change of NT-proBNP compared to its baseline was also larger with dapagliflozin (-34.89% vs -10.085%, P = 0.001). Additionally, higher cumulative UOP was found at day 4 (18600 ml in dapagliflozin vs 13700 in placebo, P = 0.031). Dapagliflozin decreased rehospitalization rates within 30 days after discharge, while it did not affect the spot urinary Na concentration, incidence of worsening of heart failure, or mortality rates.

CONCLUSION

Dapagliflozin may provide symptomatic relief and improve diuresis in patients with AHF. Further studies are needed to confirm these findings. https://clinicaltrials.gov/study/NCT05406505.

Fluid balance in heart failure

Fluid retention is a major determinant of symptoms in patients with heart failure (HF), and it is closely associated with prognosis. Hence, congestion represents a critical therapeutic target in this clinical setting. The first therapeutic strategy in HF patients with fluid overload is optimization of diuretic intervention to maximize water and sodium excretion. When diuretic therapy fails to relieve congestion, renal replacement therapy represents the only alternative option for fluid removal, as well as a way to restore diuretic responsiveness. On this background, the pathophysiology of fluid balance in HF is complex, with heart, kidney, and lung being deeply involved in volume regulation and management. Therefore, the interplay between these organs should be appreciated and considered when fluid overload in HF patients is targeted.

Serial evaluation of loop diuretic efficiency following left ventricular assist device implantation

More than 50% of heart failure (HF) patients require diuretic therapy after left ventricular assist device (LVAD). Although few data related to diuretic response (DR) exist in stage D patients, tubular sodium reabsorption may be clinically prognostic independent of estimated glomerular filtration rate (eGFR) and proteinuria within this cohort. We aimed to characterize DR serially before and after LVAD implantation in a stage D population. We conducted a prospective, observational cohort study of HF patients receiving diuretics with plans to undergo LVAD implantation. We measured urine sodium (UNa) and creatinine (UCr) at three points after diuretic therapy: pre-LVAD, post-LVAD prior to discharge, and as an outpatient. Prior to LVAD, patients (N = 19) had an average eGFR of 54.0 ± 18.0 mL/min/1.73 m2, spot UNa of 74.8 ± 28.0 mmol/L, and fractional excretion of sodium (FENa) of 3.1 ± 2.7%. Pre-LVAD, eGFR did not correlate with spot UNa nor FENa (p > 0.05 for both). LVAD implantation did not improve DR post-LVAD (mean change FENa per 40 mg IV furosemide 0.5 ± 1.0%; p = 0.84), and 90% of patients required loop diuretics at 90 days post-surgery. Improved hemodynamics following LVAD may not improve DR or tubular function; larger studies are needed to confirm our results and assess the utility of DR to predict post-LVAD outcomes.

Natriuresis-guided diuretic therapy in acute heart failure: a pragmatic randomized trial

Measurement of natriuresis has been suggested as a reliable, easily obtainable biomarker for assessment of the response to diuretic treatment in patients with acute heart failure (AHF). Here, to assess whether natriuresis-guided diuretic therapy in patients with AHF improves natriuresis and clinical outcomes, we conducted the pragmatic, open-label Pragmatic Urinary Sodium-based algoritHm in Acute Heart Failure trial, in which 310 patients (45% female) with AHF requiring treatment with intravenous loop diuretics were randomly assigned to natriuresis-guided therapy or standard of care (SOC). In the natriuresis-guided arm, natriuresis was determined at set timepoints, prompting treatment intensification if spot urinary sodium levels were <70 mmol l-1. The dual primary endpoints were 24 h urinary sodium excretion and a combined endpoint of time to all-cause mortality or adjudicated heart failure rehospitalization at 180 days. The first primary endpoint was met, as natriuresis in the natriuresis-guided and SOC arms was 409 ± 178 mmol arm versus 345 ± 202 mmol, respectively (P = 0.0061). However, there were no significant differences between the two arms for the combined endpoint of time to all-cause mortality or first heart failure rehospitalization, which occurred in 46 (31%) and 50 (31%) of patients in the natriuresis-guided and SOC arms, respectively (hazard ratio 0.92 [95% confidence interval 0.62-1.38], P = 0.6980). These findings suggest that natriuresis-guided therapy could be a first step towards personalized treatment of AHF. ClinicalTrials.gov registration: NCT04606927 .

The Association Between Intra-abdominal Pressure and Diuretic Response in Heart Failure

PURPOSE OF THE REVIEW

An efficient diuretic response is vital during cardiac decompensation in heart failure (HF) patients. The increase in intra-abdominal pressure (IAP) could be one of the keys for understanding cardiorenal syndrome and guiding diuretic treatment during hospitalization. In this review, we analyze the relationship between IAP and diuretic response in HF patients.

RECENT FINDINGS

Increased IAP is associated with worsening renal function (WRF) in patients with advanced HF. Furthermore, the persistence of a rise in IAP after the first 72 h of intravenous diuretic treatment has been correlated with a worse diuretic response, a higher degree of congestion, and an impaired prognosis. The rise in IAP in HF patients has been associated with impaired renal function and a lower diuretic response. Nonetheless, more studies are needed to elucidate the actual role of IAP in congestive nephropathy and whether it may help guide diuretic therapy during acute decompensations.

Combination Diuretic Therapy With Thiazides: A Systematic Review on the Beneficial Approach to Overcome Refractory Fluid Overload in Heart Failure

Heart failure (HF) is a notable public health issue, and intravenous loop diuretics are frequently employed to address acute decompensated heart failure (ADHF) and alleviate symptoms of congestion. However, prolonged use of loop diuretics can lead to drug resistance, and some patients experience refractory volume overload that does not respond to treatment. Sequential nephron blockade, which involves combining loop and thiazide diuretics, has been proposed as a strategy to overcome diuretic resistance and improve fluid overload management. This systematic review aims to critically evaluate the effectiveness and safety of this combination diuretic therapy. Following the directives detailed in the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a comprehensive search was conducted. Eligibility criteria were established to select relevant studies, including the requirement for studies to be conducted on human subjects and published as free full-text papers in English within the last 10 years. Several databases were searched using a combination of Medical Subject Heading (MeSH) phrases and keywords related to heart failure, loop diuretics, and thiazide diuretics. The search yielded 948 references, and after screening titles, abstracts, and full-text papers, eight final studies (five observational studies and three randomized control trials) were included in the review. Based on the findings of this systematic review, there is substantial evidence to endorse the efficacy of combination diuretic therapy of loop and thiazide diuretics in augmenting diuresis and enhancing outcomes for patients who exhibit insufficient responses to single-agent diuretics. Additionally, the review provides valuable insights about the timing and type of diuretics to use, helping clinicians make informed therapeutic decisions. However, to ensure patient safety and well-being, it is imperative to take into account the potential for electrolyte disturbances and impacts on renal function, necessitating diligent and vigilant monitoring as well as effective management strategies. In light of these findings, further research is warranted to optimize the dosing regimens and to delve deeper into the long-term safety and efficacy of combination therapy. Such research endeavors will undoubtedly contribute to refining treatment approaches and advancing patient care in the field of HF management.

Sodium-glucose cotransporter-2 inhibitors in heart failure: Potential decongestive mechanisms and current clinical studies

Congestion is a key pathophysiological feature of heart failure (HF) syndrome that drives most of the clinical manifestations of acute HF and is related with poor quality of life and outcomes. Therefore, safe and effective decongestion is an important therapeutic target in the management of acute HF and despite the use of guideline-recommended loop diuretics, adequate decongestion is not always achieved in patients with acute HF. Recently, sodium-glucose cotransporter-2 (SGLT-2) inhibitors have been shown to provide clinical benefits across a broad spectrum of patients with HF, including consistent reduction in the risk of acute HF episodes. While the exact mechanisms underlying these benefits remain a matter of debate, a growing body of evidence suggests that effective decongestion may be partly responsible, especially in the setting of acute HF. In this review, we discuss the potential decongestive mechanisms of SGLT-2 inhibitors, such as osmotic diuresis, natriuresis, preservation of glomerular filtration and facilitation of interstitial drainage, which can collectively translate into effective and safe decongestion. Furthermore, we provide a comprehensive review of up-to-date clinical data of SGLT-2 inhibitor use in the acute HF population.

Diuretic-resistant heart failure and the role of ultrafiltration: A proposed protocol

Acute heart failure (HF) decompensation generally manifests with signs and symptoms of congestion that strongly predict poor poor patient outcome. Loop diuretics are the cornerstone of therapy to counteract fluid overload and are widely used for acute management and chronic stabilization of HF. However, a diminished response to loop diuretics is a common problem, affecting the patient's clinical course and potentially prolonging hospitalization. Diuretic resistance is defined as failure to decongest despite appropriate and escalating loop diuretic therapy. We propose a protocol for the management of diuretic resistance. The initial approach should include an assessment of causes of pseudo-diuretic resistance. Adjustments to loop diuretic therapy, such as increasing doses and frequency of administration and sequential nephron blockade, may be successful. For hospitalized patients with progressive disease there are more invasive methods for fluid removal. Switching from oral to intravenous loop diuretics is essential to avoid variable absorption and for symptomatic relief. Extracorporeal ultrafiltration is also an option since this technique is highly effective at removing plasma fluid from blood. While extracorporeal ultrafiltration is an invasive solution, peritoneal dialysis is a home-based, intermittent therapeutic option that can enable efficient management of fluid overload, preventing HF-related hospital admission, and improving quality of life. As a last resort for fluid removal, a peritoneal dialysis regimen should fully exploit its decongestive properties and should be tailored to the patient's characteristics and clinical needs.

The importance of forward flow and venous congestion in diuretic response in acute heart failure: Insights from the ESCAPE trial

AIMS

Previous studies have suggested venous congestion as a stronger mediator of negative cardio-renal interactions than low cardiac output, with neither factor having a dominant role. While the influence of these parameters on glomerular filtration have been described, the impact on diuretic responsiveness is unclear. The goal of this analysis was to understand the hemodynamic correlates of diuretic response in hospitalized patients with heart failure.

METHODS AND RESULTS

We analyzed patients from the Evaluation Study of Congestive Heart Failure and Pulmonary Artery Catheterization Effectiveness (ESCAPE) dataset. Diuretic efficiency (DE) was defined as the average daily net fluid output per doubling of the peak loop diuretic dose. We evaluated a pulmonary artery catheter hemodynamic-guided cohort (n = 190) and a transthoracic echocardiogram (TTE) cohort (n = 324) where DE was evaluated with hemodynamic and TTE parameters. Metrics of "forward flow" such as cardiac index, mean arterial pressure and left ventricular ejection fraction were not associated with DE (p > 0.2 for all). Worse baseline venous congestion was paradoxically associated with better DE as assessed by right atrial pressure (RAP), right atrial area (RAA), and right ventricular systolic and diastolic area (p < 0.05 for all). Renal perfusion pressure (capturing both congestion and forward flow) was not associated with diuretic response (p = 0.84).

CONCLUSIONS

Worse venous congestion was weakly associated with better loop diuretic response. Metrics of "forward flow" did not demonstrate any correlation with diuretic response. These observations raise questions about the concept of central hemodynamic perturbations as the primary drivers of diuretic resistance on a population level in HF.

Low Plasma Levels of Irisin Predict Acutely Decompensated Heart Failure in Type 2 Diabetes Mellitus Patients with Chronic Heart Failure

The aim of this study was to determine the discriminative value of irisin for acutely decompensated heart failure (ADHF) in type 2 diabetes mellitus (T2DM) patients with chronic HF. We included 480 T2DM patients with any phenotype of HF and followed them for 52 weeks. Hemodynamic performances and the serum levels of biomarkers were detected at the study entry. The primary clinical end-point was ADHF that led to urgent hospitalization. We found that the serum levels of N-terminal natriuretic pro-peptide (NT-proBNP) were higher (1719 [980-2457] pmol/mL vs. 1057 [570-2607] pmol/mL, respectively) and the levels of irisin were lower (4.96 [3.14-6.85] ng/mL vs. 7.95 [5.73-9.16] ng/mL) in ADHF patients than in those without ADHF. The ROC curve analysis showed that the estimated cut-off point for serum irisin levels (ADHF versus non-ADHF) was 7.85 ng/mL (area under curve [AUC] = 0.869 (95% CI = 0.800-0.937), sensitivity = 82.7%, specificity = 73.5%; p = 0.0001). The multivariate logistic regression yielded that the serum levels of irisin < 7.85 ng/mL (OR = 1.20; p = 0.001) and NT-proBNP > 1215 pmol/mL (OR = 1.18; p = 0.001) retained the predictors for ADHF. Kaplan-Meier plots showed a significant difference of clinical end-point accumulations in patients with HF depending on irisin levels (<7.85 ng/mL versus ≥7.85 ng/mL). In conclusion, we established that decreased levels of irisin were associated with ADHF presentation in chronic HF patients with T2DM independently from NT-proBNP.

Impact of the time-to-target rate of urine volume concept on the outcome of acute decompensated heart failure

BACKGROUND

Early decongestion with diuretics could improve clinical outcomes. This study aimed to examine the impact of the time-to-target rate of urine volume (T2TUV) concept on the outcome of acute decompensated heart failure (ADHF).

METHODS

This multicenter retrospective study included 1670 patients with ADHF who received diuretics within 24 h of admission. T2TUV was defined as the time from admission to the rate of urine volume of 100 ml/h. The primary outcomes were in-hospital death, mortality, and re-hospitalization for 1 year.

RESULTS

A total of 789 patients met the inclusion criteria (T2TUV on day 1, n = 248; day 2-3, n = 172; no target rate UV, n = 369). In-hospital mortality in the day 1 group was significantly lower (2.7% vs. 5.9% vs. 11.1%; p < 0.001) than that of other groups. The mortality and re-hospitalization for 1 year in the day 1 group was significantly lower (event-free rate: 67.7% vs. 54.1% vs. 56.9%; log-lank p = 0.004) than that of other groups. In multivariate analysis, predictors of T2TUV at day 1 were age (odds ratio [OR]: 1.02, 95% confidence interval [CI]: 1.01-1.04, p = 0.007), previous hospitalized heart failure (OR: 1.47, 95% CI: [1.03-2.12], p = 0.03), N-terminal-pro B type natriuretic peptide per 1000 pg/ml (OR: 1.02, 95% CI: 1.01-1.04, p = 0.007), carperitide (OR: 0.69, 95% CI: 0.48-0.99, p = 0.05), and early administration of tolvaptan (OR: 0.6, 95% CI: 0.42-0.85, p = 0.004).

CONCLUSIONS

T2TUV of less than day 1 was associated with lower in-hospital mortality and decreased mortality and re-hospitalization at 1 year.

Impact of mitral regurgitation in patients with acute heart failure: insights from the RELAX-AHF-2 trial

AIMS

The impact of mitral regurgitation (MR) in patients hospitalized for acute heart failure (AHF) is not well established. We assessed the role of MR in patients enrolled in the Relaxin in Acute Heart Failure 2 (RELAX-AHF-2) trial.

METHODS AND RESULTS

Patients enrolled in RELAX-AHF-2 with available data regarding MR status were included in this analysis. Baseline characteristics, in-hospital data, and clinical outcomes through 180-day follow-up were evaluated. The impact of moderate/severe MR was assessed. Among 6420 AHF patients with known MR status, 1810 patients (28.2%) had moderate/severe MR. Compared to patients with no/mild MR, those with moderate/severe MR were more likely to have history of heart failure (HF), prior HF hospitalization, more comorbidities, symptoms/signs of HF, lower left ventricular ejection fraction and higher N-terminal pro-B-type natriuretic peptide levels. Moderate/severe MR was associated with longer length of hospital stay, higher rates of residual dyspnoea, increased jugular venous pressure through the index hospitalization and a higher unadjusted risk of the composite of cardiovascular (CV) death or rehospitalization for HF/renal failure (RF) through 180 days (crude hazard ratio [HR] 1.15, 95% confidence interval [CI] 1.03-1.27, p = 0.01). The association between moderate/severe MR and poorer outcomes was not maintained in a multivariable model including several covariates of interest (adjusted HR 1.03, 95% CI 0.91-1.17, p = 0.65). Similar findings were observed for HF/RF rehospitalization alone.

CONCLUSIONS

In patients with AHF, moderate/severe MR was associated with a worse clinical profile but did not have an independent prognostic impact on clinical outcomes.

New Insight in Cardiorenal Syndrome: From Biomarkers to Therapy

Cardiorenal syndrome consists in the coexistence of acute or chronic dysfunction of heart and kidneys resulting in a cascade of feedback mechanisms and causing damage to both organs associated with high morbidity and mortality. In the last few years, different biomarkers have been investigated with the aim to achieve an early and accurate diagnosis of cardiorenal syndrome, to provide a prognostic role and to guide the development of targeted pharmacological and non-pharmacological therapies. In such a context, sodium-glucose cotransporter 2 (SGLT2) inhibitors, recommended as the first-line choice in the management of heart failure, might represent a promising strategy in the management of cardiorenal syndrome due to their efficacy in reducing both cardiac and renal outcomes. In this review, we will discuss the current knowledge on the pathophysiology of cardiorenal syndrome in adults, as well as the utility of biomarkers in cardiac and kidney dysfunction and potential insights into novel therapeutics.

Predictors of Poor Very Early Diuretic Response and Effectiveness of Early Tolvaptan in Symptomatic Acute Heart Failure

BACKGROUND

Diuretic response (DR) in patients with symptomatic acute decompensated heart failure (ADHF) has an impact on prognosis. This study aimed to identify predictive factors influencing acute 6 h poor DR and to assess DR after early administration of tolvaptan (TLV).

METHODS

This multicenter retrospective study included 1670 patients who were admitted for ADHF and received intravenous furosemide within 1 h of presentation in clinical scenario 1 or 2 defined based on initial systolic blood pressure ≥100 mmHg with severe symptoms (New York Heart Association class III or IV (n = 830). The score for the poor DR factors in the very acute phase was calculated in patients treated with furosemide-only diuretics (n = 439). The DR to TLV administration was also assessed in patients who received an additional dose of TLV within 6 h (n = 391).

RESULTS

The time since discharge from the hospital for a previous heart failure < 3 months (odds ratio [OR] 2.78, 95% confidence interval [CI] 1.34-5.83; p = 0.006), loop diuretics at admission (OR 3.05, 95% CI 1.74-5.36; p < 0.0001), and estimated glomerular filtration rate (eGFR) < 45 mL/min/1.73 m² (OR 2.99, 95% CI 1.58-5.74; p = 0.0007) were independent determinants of poor DR. The frequency of poor DR according to the risk stratification group was low risk (no risk factor), 18.9%; middle risk (one risk factor), 33.1%; and high risk (two to three risk factors), 58.0% (p < 0.0001). All risk groups demonstrated a significantly lower incidence of poor DR with early TLV administration: 10.7% in the early TLV group versus 18.9% in the loop diuretics group (p = 0.09) of the low-risk group; 18.4% versus 33.1% (p = 0.01) in the middle-risk group, and 20.2% versus 58.0% (p < 0.0001) in the high-risk group.

CONCLUSION

Early administration of TLV in patients with predicted poor DR contributed to a significant diuretic effect and suppression of worsening renal function.

Early treatment with a sodium-glucose co-transporter 2 inhibitor in high-risk patients with acute heart failure: Rationale for and design of the EMPA-AHF trial

AIMS

The aim of the EMPA-AHF trial is to clarify whether early initiation of a sodium-glucose co-transporter 2 inhibitor before clinical stabilization is safe and beneficial for patients with acute heart failure (AHF) who are at a high risk of adverse events.

METHODS

The EMPA-AHF trial is a randomized, double-blind, placebo-controlled, multicentre trial examining the efficacy and safety of early initiation of empagliflozin (10 mg once daily). In total, 500 patients admitted for AHF will be randomized 1:1 to either empagliflozin 10 mg daily or placebo at 47 sites in Japan. Study entry requires hospitalization for AHF with dyspnoea, signs of volume overload, elevated natriuretic peptide, and at least one of the following criteria: estimated glomerular filtration rate <60 mL/min/1.73 m²; already taking ≥40 mg of furosemide daily before hospitalization; and urine output of <300 mL within 2 hours after an adequate dose of intravenous furosemide. Patients will be randomized within 12 hours of hospital presentation, with treatment continued up to 90 days. The primary outcome is the clinical benefit of empagliflozin on the win ratio for a hierarchical composite endpoint consisting of death within 90 days, heart failure rehospitalization within 90 days, worsening heart failure during hospitalization, and urine output within 48 hours after treatment initiation.

CONCLUSION

The EMPA-AHF trial is the first to evaluate the efficacy and safety of early initiation of empagliflozin in patients with AHF considered to be at high risk under conventional treatment.

Renal Assessment in Acute Cardiorenal Syndrome

Cardiorenal syndrome (CRS) is a complex, heterogeneous spectrum of symptoms that has kept cardiologists awake for decades. The heart failure (HF) population being burdened with multimorbidity poses diagnostic and therapeutic challenges even for experienced clinicians. Adding deteriorated renal function to the equation, which is one of the strongest predictors of adverse outcome, we measure ourselves against possibly the biggest problem in modern cardiology. With the rapid development of new renal assessment methods, we can treat CRS more effectively than ever. The presented review focuses on explaining the pathophysiology, recent advances and current practices of monitoring renal function in patients with acute CRS. Understanding the dynamic interaction between the heart and the kidney may improve patient care and support the selection of an effective and nephroprotective treatment strategy.

Disconnect between the effects of serelaxin on renal function and outcome in acute heart failure

BACKGROUND

We aimed to study whether improvement in renal function by serelaxin in patients who were hospitalized for acute heart failure (HF) might explain any potential effect on clinical outcomes.

METHODS

We included 6318 patients from the RELAXin in AHF-2 (RELAX-AHF2) study. Improvement in renal function was defined as a decrease in serum creatinine of ≥ 0.3 mg/dL and ≥ 25%, or increase in estimated glomerular filtration rate of ≥ 25% between baseline and day 2. Worsening renal function (WRF) was defined as the reverse. We performed causal mediation analyses regarding 180-day all-cause mortality (ACM), cardiovascular death (CVD), and hospitalization for HF/renal failure.

RESULTS

Improvement in renal function was more frequently observed with serelaxin when compared with placebo [OR 1.88 (95% CI 1.64-2.15, p < 0.0001)], but was not associated with subsequent clinical outcomes. WRF occurred less frequent with serelaxin [OR 0.70 (95% CI 0.60-0.83, p < 0.0001)] and was associated with increased risk of ACM, worsening HF and the composite of CVD and HF or renal failure hospitalization. Improvement in renal function did not mediate the treatment effect of serelaxin [CVD HR 1.01 (0.99-1.04), ACM HR 1.01 (0.99-1.03), HF/renal failure hospitalization HR 0.99 (0.97-1.00)].

CONCLUSIONS

Despite the significant improvement in renal function by serelaxin in patients with acute HF, the potential beneficial treatment effect was not mediated by improvement in renal function. These data suggest that improvement in renal function might not be a suitable surrogate marker for potential treatment efficacy in future studies with novel relaxin agents in acute HF. Central illustration. Conceptual model explaining mediation analysis; treatment efficacy of heart failure therapies mediated by renal function.

Impact of empagliflozin on decongestion in acute heart failure: the EMPULSE trial

AIMS

Effective and safe decongestion remains a major goal for optimal management of patients with acute heart failure (AHF). The effects of the sodium-glucose cotransporter 2 inhibitor empagliflozin on decongestion-related endpoints in the EMPULSE trial (NCT0415775) were evaluated.

METHODS AND RESULTS

A total of 530 patients hospitalized for AHF were randomized 1:1 to either empagliflozin 10 mg once daily or placebo for 90 days. The outcomes investigated were: weight loss (WL), WL adjusted for mean daily loop diuretic dose (WL-adjusted), area under the curve of change from baseline in N-terminal pro-B-type natriuretic peptide levels, hemoconcentration, and clinical congestion score after 15, 30, and 90 days of treatment. Compared with placebo, patients treated with empagliflozin demonstrated significantly greater reductions in all studied markers of decongestion at all time-points, adjusted mean differences (95% confidence interval) at Days 15, 30, and 90 were: for WL -1.97 (-2.86, -1.08), -1.74 (-2.73, -0.74); -1.53 (-2.75, -0.31) kg; for WL-adjusted: -2.31 (-3.77, -0.85), -2.79 (-5.03, -0.54), -3.18 (-6.08, -0.28) kg/40 mg furosemide i.v. or equivalent; respectively (all P < 0.05). Greater WL at Day 15 (i.e. above the median WL in the entire population) was associated with significantly higher probability for clinical benefit at Day 90 (hierarchical composite of all-cause death, heart failure events, and a 5-point or greater difference in Kansas City Cardiomyopathy Questionnaire total symptom score change from baseline to 90 days) with the win ratio of 1.75 (95% confidence interval 1.37, 2.23; P < 0.0001).

CONCLUSION

Initiation of empagliflozin in patients hospitalized for AHF resulted in an early, effective and sustained decongestion which was associated with clinical benefit at Day 90.

A Machine Learning Model to Predict Diuretic Resistance

BACKGROUND

Volume overload is a common complication encountered in hospitalized patients, and the mainstay of therapy is diuresis. Unfortunately, the diuretic response in some individuals is inadequate despite a typical dose of loop diuretics, a phenomenon called diuretic resistance. An accurate prediction model that predicts diuretic resistance using predosing variables could inform the right diuretic dose for a prospective patient.

METHODS

Two large, deidentified, publicly available, and independent intensive care unit (ICU) databases from the United States were used-the Medical Information Mart for Intensive Care III (MIMIC) and the Philips eICU databases. Loop diuretic resistance was defined as <1400 ml of urine per 40 mg of diuretic dose in 24 hours. Using 24-hour windows throughout admission, commonly accessible variables were obtained and incorporated into the model. Data imputation was performed using a highly accurate machine learning method. Using XGBoost, several models were created using train and test datasets from the eICU database. These were then combined into an ensemble model optimized for increased specificity and then externally validated on the MIMIC database.

RESULTS

The final ensemble model was composed of four separate models, each using 21 commonly available variables. The ensemble model outperformed individual models during validation. Higher serum creatinine, lower systolic blood pressure, lower serum chloride, higher age, and female sex were the most important predictors of diuretic resistance (in that order). The specificity of the model on external validation was 92%, yielding a positive likelihood ratio of 3.46 while maintaining overall discrimination (C-statistic 0.69).

CONCLUSIONS

A diuretic resistance prediction model was created using machine learning and was externally validated in ICU populations. The model is easy to use, would provide actionable information at the bedside, and would be ready for implementation in existing electronic medical records. This study also provides a framework for the development of future machine learning models.

Enhancing Sweat Rate Using a Novel Device for the Treatment of Congestion in Heart Failure

BACKGROUND

Current treatment of fluid retention in heart failure relies primarily on diuretics. However, adequate decongestion is not achieved in many patients. We aimed to study the feasibility and short-term performance of a novel approach to remove fluids and sodium directly from the interstitial compartment by enhancing sweat rate.

METHODS

We used a device designed to enhance fluid and salt loss via the eccrine sweat glands. Skin temperature in the lower body was increased from 35 °C to 38 °C, where the slope of the relationship between temperature and sweat production is linear. The sweat evaporates instantaneously, thus avoiding the awareness of perspiration. The primary efficacy endpoint was the ability to increase skin temperature to the desired range. A secondary efficacy endpoint was a clinically meaningful hourly sweat output, defined as ≥150 mL/h. The primary safety endpoint was any procedure-related adverse events.

RESULTS

We studied 6 normal subjects and 18 patients with congestion. Participants underwent 3 treatment sessions of up to 4 hours. Skin temperature increased to a median of 37.5 °C (interquartile range, 37.1-37.9 °C) with the median core temperature increasing by 0.2 °C (interquartile range, 0.1-0.3 °C). The median hourly weight loss during treatment was 215 g/h (interquartile range, 165-285; range, 100-344 g/h). In 80% of treatment procedures, the average sweat rate was ≥150 mL/h. There were no significant changes in hemodynamic variables or renal function and no procedure-related adverse events.

CONCLUSIONS

Enhancing sweat rate was safe and resulted in a clinically meaningful fluid removal and weight loss.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT04578353.

Early drop in systolic blood pressure is associated with poor diuretic response and prognosis in patients with acute heart failure

AIMS

Although an excessive drop in systolic blood pressure (SBP) during acute heart failure (AHF) negatively impacts prognosis, the association between changes in SBP and the diuretic response (DR) is unclear. We aimed to clarify the association between an early drop in SBP and DR/prognosis in patients with AHF.

METHODS AND RESULTS

This was a sub-analysis of the REALITY-AHF study, which registered patients with AHF admitted through emergency departments (EDs). An early SBP drop was defined as the difference between baseline SBP and the lowest value during the first 48 h of hospitalization. DR was defined as the urine output achieved per 40 mg of intravenous furosemide administered. SBP was measured on admission, at 90 min, and 6, 24, and 48 h after admission. Patients were divided into four groups according to their median SBP drop and DR: greater SBP drop/poor DR (n = 322), smaller SBP drop/poor DR (n = 409), greater SBP drop/good DR (n = 419), and smaller SBP drop/good DR (n = 314). The study included 1,464 patients. A greater SBP drop/poor DR was associated with higher baseline SBP and vasodilator use. Multivariable linear regression analysis showed that a greater drop in SBP was associated with poorer DR following adjustment for potential covariates. Cox proportional hazards analysis demonstrated that a greater SBP drop/poor DR was independently associated with 1-year mortality. Both SBP and DR changes were independently associated with prognosis.

CONCLUSION

An early drop in SBP during the first 48 h of hospitalization was associated with poor DR and 1-year mortality in patients with AHF.

CLINICAL TRIAL REGISTRATION

URL: http://www.umin.ac.jp/ctr/Unique identifier: UMIN000014105.

Mechanized lymphatic drainage in acute decompensated heart failure. A study on a hydrodynamic test bench

Objective: to investigate the effectiveness of a new mechanized lymphatic drainage method in acute decompensated heart failure (ADHF) modeling through local reduction in venous pressure in the site of lymphatic drainage from the thoracic duct.

Materials and methods. Main components of the device are a catheter with built-in inlet and outlet mechanical valves designed for insertion into the left brachiocephalic vein through the left internal jugular vein. It comes with an extracorporeal drive system made as a valveless pulsator pump with a 10 ml shock discharge and a controller ensuring preset frequency and pressure/rarefaction duty cycle. The operating principle of the device is based on local reduction of venous pressure in the site of lymphatic drainage from the thoracic duct (in the junction of the left internal jugular and subclavian veins).

Results. When modeling hydrodynamics under ADHF conditions on a hydrodynamic test bench, the upper venous flow through the left brachiocephalic vein was 0.4 l/min, the pressure in the site of lymphatic drainage from the thoracic duct, was decreased from 20–25 mmHg to 0–5 mmHg due to operation of the mechanized drainage device with suction/injection phase duration ratio 0.2/0.8 and pulsator pump operating frequency from 30 to 60 beats/min.

Right Heart Function in Cardiorenal Syndrome

Purpose of Review

Since CRS is critically dependent on right heart function and involved in interorgan crosstalk, assessment and monitoring of both right heart and kidney function are of utmost importance for clinical outcomes. This systematic review aims to comprehensively report on novel diagnostic and therapeutic paradigms that are gaining importance for the clinical management of the growing heart failure population suffering from CRS.

Recent Findings

Cardiorenal syndrome (CRS) in patients with heart failure is associated with poor outcome. Although systemic venous congestion and elevated central venous pressure have been recognized as main contributors to CRS, they are often neglected in clinical practice. The delicate hemodynamic balance in CRS is particularly determined by the respective status of the right heart.

Summary

The consideration of hemodynamic and CRS profiles is advantageous in tailoring treatment for better preservation of renal function. Assessment and monitoring of right heart and renal function by known and emerging tools like renal Doppler ultrasonography or new biomarkers may have direct clinical implications.

Effect of Hypertonic Saline Solution Combined with Furosemide on Acute Heart Failure: A Meta-Analysis

Background

The efficacy of hypertonic saline solution (HSS) combined with furosemide in treating acute heart failure is controversial. This meta-analysis explores the efficacy of HSS combined with furosemide for the treatment of acute heart failure.

Methods

Literature were searched from databases, including PubMed, Web of Knowledge, Embase, Central, CMKI, Wanfang, and VIP. The inclusion criteria were as follows: (1) subjects: patients with acute heart failure; (2) the experimental group and the control group were properly set up; (3) intervention measures: patients in the experimental group were treated with HSS + furosemide, and patients in the control group were treated with furosemide; (4) the outcomes included at least one of the following indicators: readmission rate, mortality, 24 h urine volume, weight loss, and serum creatinine; and (5) randomized controlled trial (RCT). The method recommended by Cochrane Collaboration Network was used to evaluate the risk bias. The heterogeneity among the studies was evaluated through the chi-square test, and the publication bias was assessed by the Egger test. The results were described using risk ratio (RR), mean difference (MD), and 95% confidence interval (CI).

Results

The readmission rate in the HSS + furosemide group was lower than that in the furosemide group (RR = 0.53, 95% CI [0.46, 0.60], P < 0.00001), with no heterogeneity among the literature (P = 0.21, I² = 29%). Patients in the HSS + furosemide group had a lower mortality rate than that in the furosemide group (RR = 0.55, 95% CI [0.46, 0.65], P < 0.00001). The chi-square test result indicated no heterogeneity among the literature (P = 0.25, I² = 23%). Furthermore, the 24 h urine volume of patients in the HSS + furosemide group was higher than that in the furosemide group (MD = 497.29, 95% CI [457.61, 536.96], P < 0.00001). There was no heterogeneity among the literature (P = 0.58, I² = 0%). In contrast, patients in the HSS + furosemide group demonstrated a lower serum creatinine level than those in the furosemide group (MD = −0.45, 95% CI [-0.51, -0.39], P < 0.00001). However, heterogeneity was observed among the literature (P < 0.00001, I² = 81%). The weight loss in the HSS + furosemide group was higher than that in the furosemide group (MD = 1.83, 95% CI [1.51, 2.15], P < 0.00001). There was no heterogeneity among the literature (P = 0.42, I² = 2%). Egger test showed no publication bias among the literature (P > 0.05).

Conclusion

Despite the heterogeneity and bias in our study, the combination of HSS with furosemide is promising in patients with acute heart failure. However, further research is still needed to confirm.

Relation of Low Chloride Concentration to Diuretic Efficiency and Transplant-Free Survival in Children Hospitalized With Heart Failure

Serum chloride plays an important role in fluid homeostasis and is associated with impaired diuretic responsiveness and mortality in adults with heart failure (HF). We sought to characterize the relationship of serum chloride and diuretic efficiency (DE) and to determine its prognostic importance in children hospitalized with acute decompensated HF (ADHF). We studied DE, defined as net fluid output/kg+constant per mg of loop diuretic/kg, in 200 children hospitalized with ADHF. Median serum chloride at admission was 102 mmol/L (interquartile range 99 to 105 mmol/L), and hypochloremia (chloride ≤96 mmol/L) was present in 16% of the population at admission. Serum chloride correlated with serum sodium (r = 0.66; p < 0.001) and bicarbonate (r = -0.39; p < 0.001). In the adjusted analysis, lower chloride was associated with reduced DE (p < 0.001). Serum sodium was associated with DE on the unadjusted analysis; however, the association was eliminated when added to the model with chloride (p = 0.442). Lower chloride was also associated with features of inadequate decongestion during hospitalization: a positive fluid balance (p = 0.003), greater cumulative loop diuretic dose per weight (p = 0.001), addition of a thiazide diuretic during hospitalization (p < 0.001), less weight loss (p = 0.025), and longer length of stay (p = 0.003). Chloride concentration was independently associated with death or transplant 1 year after admission (hazard ratio 0.94; p < 0.001). As a dichotomous variable, hypochloremia was independently associated with reduced DE (p < 0.001) and decreased 1-year transplant-free survival (hazard ratio 2.3, p < 0.001). Lower serum chloride at hospital admission is strongly and independently associated with impaired DE and reduced transplant-free survival in children hospitalized with ADHF.

Mechanistic Insights in Cardiorenal Syndrome

Mechanistic Insights in Cardiorenal SyndromeLo and Rangaswami review the pathophysiology and management of cardiorenal syndrome, with a focus on decongestion, interpretation of kidney function, and implementation of guideline directed medical therapies.

Comprehensive and Safe Decongestion in Acutely Decompensated Heart Failure

PURPOSE OF THE REVIEW

Progressive intravascular, interstitial, and alveolar fluid overload underlies the transition from compensated to acutely decompensated heart failure and loop diuretics are the mainstay of treatment. Adverse effects and resistance to loop diuretics received much attention while the contribution of a depressed cardiac output to diuretic resistance was downplayed.

RECENT FINDINGS

Analysis of experience with positive inotropic agents, especially dobutamine, indicates that enhancement of cardiac output is not consistently associated with increased renal blood flow. However, urinary output and renal sodium excretion increase likely due to dobutamine-mediated decrease in renal and systemic reduced activation of sympathetic nervous- and renin-angiotensin-aldosterone system. Mechanical circulatory support with left ventricular assist devices ascertained the contribution of low cardiac output to diuretic resistance and the pathogenesis and progression of kidney disease in acutely decompensated heart failure. Diuretic resistance commonly occurs in acutely decompensated heart failure. However, failure to resolve fluid overload despite high doses of loop diuretics should alert to the presence of a low cardiac output state.

Neuroendocrine hormone status and diuretic response to atrial natriuretic peptide in patients with acute heart failure

AIMS

Given the various effects of sacubitril/valsartan in heart failure, a deeper understanding of atrial natriuretic peptide (ANP) actions is warranted. Natriuresis is a fundamental action of ANP in acute heart failure (AHF), whereas the diuretic effect of ANP is different in each patient according to the diversity of renal response to ANP, which is affected by baseline plasma ANP status and deficiency of circulating ANP. Meanwhile, associations between other neuroendocrine hormones and the diuretic response to ANP are unclear. This study investigated the impact of pivotal neuroendocrine hormones on the diuretic effects of exogenous ANP, carperitide.

METHODS AND RESULTS

Plasma ANP, renin, aldosterone, and vasopressin levels and the diuretic effect of 0.0125 μg/kg/min of carperitide alone for the first 6 h were prospectively evaluated in 75 patients with AHF. Lower ANP levels were significantly associated with a greater diuretic response to exogenous ANP (r = -0.35, P = 0.002). Additionally, higher vasopressin levels were significantly related to the poor diuretic effects of exogenous ANP (r = -0.54, P < 0.001). Plasma ANP and vasopressin concentrations were not significantly correlated (r = 0.19, P = 0.10). Baseline systolic blood pressure, renal function, and prior use of loop diuretics did not predict the diuretic response to exogenous ANP, whereas vasopressin levels independently predicted a diuretic response to exogenous ANP (P < 0.001), as well as lower plasma ANP levels (P = 0.027).

CONCLUSIONS

Vasopressin status was significantly associated with the diuretic response to exogenous ANP in AHF, independent of plasma ANP status. The results may provide a better understanding of the actions of sacubitril/valsartan.

The interstitial compartment as a therapeutic target in heart failure

Congestion is the single most important contributor to heart failure (HF) decompensation. Most of the excess volume in patients with HF resides in the interstitial compartment. Inadequate decongestion implies persistent interstitial congestion and is associated with worse outcomes. Therefore, effective interstitial decongestion represents an unmet need to improve quality of life and reduce clinical events. The key processes that underlie incomplete interstitial decongestion are often ignored. In this review, we provide a summary of the pathophysiology of the interstitial compartment in HF and the factors governing the movement of fluids between the interstitial and vascular compartments. Disruption of the extracellular matrix compaction occurs with edema, such that the interstitium becomes highly compliant, and large changes in volume marginally increase interstitial pressure and allow progressive capillary filtration into the interstitium. Augmentation of lymph flow is required to prevent interstitial edema, and the lymphatic system can increase fluid removal by at least 10-fold. In HF, lymphatic remodeling can become insufficient or maladaptive such that the capacity of the lymphatic system to remove fluid from the interstitium is exceeded. Increased central venous pressure at the site of the thoracic duct outlet also impairs lymphatic drainage. Owing to the kinetics of extracellular fluid, microvascular absorption tends to be transient (as determined by the revised Starling equation). Therefore, effective interstitial decongestion with adequate transcapillary plasma refill requires a substantial reduction in plasma volume and capillary pressure that are prolonged and sustained, which is not always achieved in clinical practice. The critical importance of the interstitium in the congestive state underscores the need to directly decongest the interstitial compartment without relying on the lowering of intracapillary pressure with diuretics. This unmet need may be addressed by novel device therapies in the near future.

Multimodal Strategies for the Diagnosis and Management of Refractory Congestion. An Integrated Cardiorenal Approach

Refractory congestion is common in acute and chronic heart failure, and it significantly impacts functional class, renal function, hospital admissions, and survival. In this paper, the pathophysiological mechanisms involved in cardiorenal syndrome and the interplay between heart failure and chronic kidney disease are reviewed. Although the physical exam remains key in identifying congestion, new tools such as biomarkers or lung, vascular, and renal ultrasound are currently being used to detect subclinical forms and can potentially impact its management. Thus, an integrated multimodal diagnostic algorithm is proposed. There are several strategies for treating congestion, although data on their efficacy are scarce and have not been validated. Herein, we review the optimal use and monitorization of different diuretic types, administration route, dose titration using urinary volume and natriuresis, and a sequential diuretic scheme to achieve a multitargeted nephron blockade, common adverse events, and how to manage them. In addition, we discuss alternative strategies such as subcutaneous furosemide, hypertonic saline, and albumin infusions and the available evidence of their role in congestion management. We also discuss the use of extracorporeal therapies, such as ultrafiltration, peritoneal dialysis, or conventional hemodialysis, in patients with normal or impaired renal function. This review results from a multidisciplinary view involving both nephrologists and cardiologists.

Renin-Angiotensin-Aldosterone System Activation and Diuretic Response in Ambulatory Patients With Heart Failure

Rationale & Objective

Heart failure treatment relies on loop diuretics to induce natriuresis and decongestion, but the therapy is often limited by diuretic resistance. We explored the association of renin-angiotensin-aldosterone system (RAAS) activation with diuretic response.

Study Design

Observational cohort.

Setting & Population

Euvolemic ambulatory adults with chronic heart failure were administered torsemide in a monitored environment.

Predictors

Plasma total renin, active renin, angiotensinogen, and aldosterone levels. Urine total renin and angiotensinogen levels.

Outcomes

Sodium output per doubling of diuretic dose and fractional excretion of sodium per doubling of diuretic dose.

Analytical Approach

Robust linear regression models estimated the associations of each RAAS intermediate with outcomes.

Results

The analysis included 56 participants, and the median age was 65 years; 50% were women, and 41% were Black. The median home diuretic dose was 80-mg furosemide equivalents. In unadjusted and multivariable-adjusted models, higher levels of RAAS measures were generally associated with lower diuretic efficiency. Higher plasma total renin remained significantly associated with lower sodium output per doubling of diuretic dose (β = -0.41 [-0.76, -0.059] per SD change) with adjustment; higher plasma total and active renin were significantly associated with lower fractional excretion of sodium per doubling of diuretic dose (β = -0.48 [-0.83, -0.14] and β = -0.51 [-0.95, -0.08], respectively) in adjusted models. Stratification by RAAS inhibitor use did not substantially alter these associations.

Limitations

Small sample size; highly selected participants; associations may not be causal.

Conclusions

Among multiple measures of RAAS activation, higher plasma total and active renin levels were consistently associated with lower diuretic response. These findings highlight the potential drivers of diuretic resistance and underscore the need for high-quality trials of decongestive therapy enhanced by RAAS blockade.

Efficacy of Nondiuretic Pharmacotherapy for Improving the Treatment of Congestion in Patients with Acute Heart Failure: A Systematic Review of Randomised Controlled Trials

Diuretic therapy is the mainstay during episodes of acute heart failure (AHF). Diuretic resistance is often encountered and poses a substantial challenge for clinicians. There is a lack of evidence on the optimal strategies to tackle this problem. This review aimed to compare the outcomes associated with congestion management based on a strategy of pharmacological nondiuretic-based regimens. The PubMed, Cochrane Library, Scopus, and ScienceDirect databases were systematically searched for all randomised controlled trials (RCTs) of adjuvant pharmacological treatments used during hospitalisation episodes of AHF patients. Congestion relief constitutes the main target in AHF; hence, only studies with efficacy indicators related to decongestion enhancement were included. The Cochrane risk-of-bias tool was used to evaluate the methodological quality of the included RCTs. Twenty-three studies were included; dyspnea relief constituted the critical efficacy endpoint in most included studies. However, substantial variations in dyspnea measurement were found. Tolvaptan and serelaxin were found to be promising options that might improve decongestion in AHF patients. However, further high-quality RCTs using a standardised approach to diuretic management, including dosing and monitoring strategies, are crucial to provide new insights and recommendations for managing heart failure in acute settings.

Diuretic Resistance Prediction and Risk Factor Analysis of Patients with Heart Failure During Hospitalization

Objectives

This study performed a prediction and risk factor analysis of diuretic resistance (DR) in patients with decompensated heart failure during hospitalization.

Methods

The data of patients with decompensated heart failure treated in 2010-2018 with DR (n = 3,383) or without DR (n = 15,444) were retrospectively collected from Chinese PLA General Hospital medical records. Statistical analysis of baseline was performed on two groups of people, and the risk factor of DR was analyzed through logic regression. Six machine learning models were built accordingly, and the adjustment of model super parameters was performed by using Bayesian optimization method. Finally, the optimal algorithm was selected according to prediction efficiency.

Results

The preliminary analysis of variance showed significant differences in the incidence of DR among patients with lung infection, hyperlipidemia, type 2 diabetes, and kidney disease. There were significant differences in estimated glomerular filtration rate (eGFR) (P < 0.001). In addition, some physical indicators like BMI were different, the laboratory results like mean red blood cell volume or C-reactive protein assay were also significantly different. The optimal classification model indicated that the best cutoff points for risk factors were vein carbon dioxide, 21 mmol/L and 29 mmol/L; total protein, 64 g/L; pro-brain natriuretic peptide (pro-BNP), 7,600 pg/mL; eGFR, 50 mL/(min ∙ 1.73 m2); serum albumin, 33 g/L; hematocrit, 0.32% and 0.56%; red blood cell volume distribution width, 13; and age, 59 years. The optimal area under the curve was 0.9512. The ranked features derived from the model were age, abnormal sodium level, pro-BNP level, serum albumin level, D-dimer level, direct bilirubin level, and eGFR.

Conclusions

The DR risk prediction model based on a gradient boosting decision tree created here identified its important risk factors. The model made very accurate predictions using simple indicators and simultaneously calculated cutoff values to help doctors predict the occurrence of DR.

Relationship between physical function at discharge and hospital meal intake in elderly patients with heart failure

The relationship between low physical function (LPF) at discharge and food intake percentage (FIP) during hospitalization is unclear. We aimed to clarify the relationship between LPF at discharge and FIP and the change in nutritional status during hospitalization in elderly patients with heart failure (HF), and determine cutoff values for FIP and change in nutritional status during hospitalization. We included 431 consecutive patients aged ≥ 65 years who were hospitalized for HF and underwent cardiac rehabilitation (CR) from 2017 to 2019. Physical function at discharge was classified into two groups according to the Short Performance Physical Battery (SPPB): low physical function (LPF) (SPPB ≤ 9) and high physical function (HPF) (SPPB > 9). We compared background, clinical parameters, pre-hospital walking level, CR progress, nutritional factors during hospitalization including FIP of the main dish and side dish, and changes in nutritional status using the Geriatric Nutritional Risk Index (ΔGNRI) at admission and discharge. Multiple logistic regression analysis was also performed. The final analysis included 213 patients (age, 81.6 years) divided into the LPF (n = 136) and HPF groups (n = 77). The LPF group showed low FIP and a high ΔGNRI value. Multivariate analysis showed FIP main dish, ΔGNRI, worsening renal function, pre-hospital walking level, and days to start of walking to be factors influencing LPF at discharge. Respective cutoff values for FIP main dish and ΔGNRI predicting LPF at discharge were 82.2% and 4.24. FIP main dish during hospitalization and ΔGNRI were associated with LPF at discharge.

Role of Early Assesment of Diuresis and Natriuresis in Detecting In-Hospital Diuretic Resistance in Acute Heart Failure

Background and Purpose: European Guidelines recommend early evaluation of diuresis and natriuresis after the first administration of diuretic to identify patients with insufficient diuretic response during acute heart failure. The aim of this work is to evaluate the prevalence and characteristics of patients with insufficient diuretic response according to this new algorithm.

Methods: Prospective observational single centre study of consecutive patients with acute heart failure and congestive signs. Clinical evaluation, echocardiography and blood tests were performed. Diuretic naïve patients received 40 mg of intravenous furosemide. Patients on an oupatient diuretic regimen received 2 times the ambulatory dose. The diuresis volume was assessed 6 h after the first loop diuretic administration, and a spot urinary sample was taken after 2 h. Insufficient diuretic response was defined as natriuresis <70 mEq/L or diuresis volume <600 ml.

Results: From January 2020 to December 2021, 73 patients were included (59% males, median age 76 years). Of these, 21 patients (28.8%, 95%CI 18.4; 39.2) had an insufficient diuretic response. Diuresis volume was <600 ml in 13 patients (18.1%), and 12 patients (16.4%) had urinary sodium <70 mEq/L. These patients had lower systolic blood pressure, worse glomerular filtration rate, and higher aldosterone levels. Ambulatory furosemide dose was also higher. These patients required more frequently thiazides and inotropes during admission.

Conclusion: The diagnostic algorithm based on diuresis and natriuresis was able to detect up to 29% of patients with insufficient diuretic response, who showed some characteristics of more advanced disease.