Loop diuretic resistance complicating acute heart failure

Diuretic resistance in acute heart failure: proposal for a new urinary sodium-based definition

BACKGROUND

Diuretic resistance is a relevant clinical issue in acute heart failure (AHF), but a standardized, quantitative definition is still missing. The aim of this analysis was to highlight discrepancies between previously proposed definitions of diuretic response and to propose a new urinary sodium (NaU)-based definition of diuretic efficiency (DE) to identify diuretic resistant (DR) patients.

METHODS

Three historical definitions of diuretic response and a new NaU-based DE definition, evaluating total NaU after the first diuretic bolus per 40 mg furosemide administered, were applied in a retrospective analysis to an AHF population treated with intravenous (i.v.) loop diuretics. Baseline characteristics, in-hospital clinical data and outcomes at discharge and mid-term follow-up were collected and compared among DR and non-DR patients for each definition.

RESULTS

Among 53 patients, 39 (73.6%), 51 (96.2%) and 3 (5.7%) were DR according to weight-derived, diuresis-derived, and spot NaU definition, respectively. The median value of the new NaU-based definition was 31 mmol/40 mg and patients were stratified accordingly. DR patients showed lower cumulative diuresis (5200 mL, 3300-6700 vs 9825 mL, 6200-12200, p = 0.007) and weight loss (4 kg, 1-5 vs 6 kg, 3-8.5, p = 0.023), higher BNP levels (808 pg/mL, 443-1037 vs 351 pg/mL, 209-859, p = 0.062) at the conclusion of protocol-guided i.v diuretic therapy, which was less frequently stopped due to decongestion in DR as compared to non-DR patients (57.7% vs 85.2%, p = 0.026). Six-months mortality or HF hospitalizations were more frequent in DR patients (OR 18.6, 95% CI 2.1-161.2, p = 0.008).

CONCLUSIONS

The NaU-based DE definition might solve discrepancies of other previously proposed definitions.

Diuretic Treatment in Patients with Heart Failure: Current Evidence and Future Directions - Part I: Loop Diuretics

PURPOSE OF REVIEW

Fluid retention or congestion is a major cause of symptoms, poor quality of life, and adverse outcome in patients with heart failure (HF). Despite advances in disease-modifying therapy, the mainstay of treatment for congestion-loop diuretics-has remained largely unchanged for 50 years. In these two articles (part I: loop diuretics and part II: combination therapy), we will review the history of diuretic treatment and the current trial evidence for different diuretic strategies and explore potential future directions of research.

RECENT FINDINGS

We will assess recent trials including DOSE, TRANSFORM, ADVOR, CLOROTIC, OSPREY-AHF, and PUSH-AHF amongst others, and assess how these may influence current practice and future research. There are few data on which to base diuretic therapy in clinical practice. The most robust evidence is for high dose loop diuretic treatment over low-dose treatment for patients admitted to hospital with HF, yet this is not reflected in guidelines. There is an urgent need for more and better research on different diuretic strategies in patients with HF.

Contemporary Decongestive Strategies in Acute Heart Failure

Congestion is the primary driver of hospital admissions in patients with heart failure and the key determinant of their outcome. Although intravenous loop diuretics remain the predominant agents used in the setting of acute heart failure, the therapeutic response is known to be variable, with a significant subset of patients discharged from the hospital with residual hypervolemia. In this context, urinary sodium excretion has gained attention both as a marker of response to loop diuretics and as a marker of prognosis that may be a useful clinical tool to guide therapy. Several decongestive strategies have been explored to improve diuretic responsiveness and removal of excess fluid. Sequential nephron blockade through combination diuretic therapy is one of the most used methods to enhance natriuresis and counter diuretic resistance. In this article, I provide an overview of the contemporary decongestive approaches and discuss the clinical data on the use of add-on diuretic therapy. I also discuss mechanical removal of excess fluid through extracorporeal ultrafiltration with a brief review of the results of landmark studies. Finally, I provide a short overview of the strategies that are currently under investigation and may prove helpful in this setting.

Conduction System Pacing: Have We Finally Found the Holy Grail of Physiological Pacing?

The late fifties are considered a high point in the history of cardiac pacing, since this era is marked by the first pacemaker implantation, which has since evolved into life-saving therapy. Right ventricular apical and biventricular pacing are the classic techniques that are recommended as first-l ine approaches for most indications in current guidelines. However, conduction system pacing has emerged as being able to deliver a more physiological form of pacing and is becoming mainstream practice in a growing number of centres. In this review, we aim to compare traditional pacing methods with conduction system pacing.

A Personalized Approach to the Management of Congestion in Acute Heart Failure

Heart failure (HF) is the common final pathway of several conditions and is characterized by hyperactivation of numerous neurohumoral pathways. Cardiorenal interaction plays an essential role in the progression of the disease, and the use of diuretics is a cornerstone in the treatment of hypervolemic patients, especially in acute decompensated HF (ADHF). The management of congestion is complex and, to avoid misinterpretations and errors, one must understand the interface between the heart and the kidneys in ADHF. Congestion itself may impair renal function and must be treated aggressively. Transitory elevations in serum creatinine during decongestion is not associated with worse outcomes and diuretics should be maintained in patients with clear hypervolemia. Monitoring urinary sodium after diuretic administration seems to improve the response to diuretics as it allows for adjustments in doses and a personalized approach. Adequate assessment of volemia and the introduction and titration of guideline-directed medical therapy are mandatory before discharge. An early visit after discharge is highly recommended, to assess for residual congestion and thus avoid readmissions.

Patient Selection and End Point Definitions for Decongestion Studies in Acute Decompensated Heart Failure: Part 1

Despite recent advances in the treatment of patients with chronic heart failure, acute decompensated heart failure remains associated with significant mortality and morbidity because many novel therapies have failed to demonstrate meaningful benefit. Persistent congestion in the setting of escalating diuretic therapy has been repeatedly shown to be a marker of poor prognosis and is currently being targeted by various emerging device-based therapies. Because these therapies inherently carry procedural risk, patient selection is key in the future trial design. However, it remains unclear which patients are at a higher risk of residual congestion or adverse outcomes despite maximally tolerated decongestive therapy. In the first part of this 2-part review, we aimed to outline patient risk factors and summarize current evidence for early recognition of high-risk profile for residual congestion and adverse outcomes. These factors are classified as relating to the following: (1) previous clinical course, (2) severity of congestion, (3) diuretic response, and (4) degree of renal impairment. We also aimed to provide an overview of key inclusion criteria in recent acute decompensated heart failure trials and investigational device studies and propose potential criteria for selection of high-risk patients in future trials.

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.

Dapagliflozin vs. metolazone in heart failure resistant to loop diuretics

BACKGROUND AND AIMS

To examine the decongestive effect of the sodium-glucose cotransporter 2 inhibitor dapagliflozin compared to the thiazide-like diuretic metolazone in patients hospitalized for heart failure and resistant to treatment with intravenous furosemide.

METHODS AND RESULTS

A multi-centre, open-label, randomized, and active-comparator trial. Patients were randomized to dapagliflozin 10 mg once daily or metolazone 5-10 mg once daily for a 3-day treatment period, with follow-up for primary and secondary endpoints until day 5 (96 h). The primary endpoint was a diuretic effect, assessed by change in weight (kg). Secondary endpoints included a change in pulmonary congestion (lung ultrasound), loop diuretic efficiency (weight change per 40 mg of furosemide), and a volume assessment score. 61 patients were randomized. The mean (±standard deviation) cumulative dose of furosemide at 96 h was 977 (±492) mg in the dapagliflozin group and 704 (±428) mg in patients assigned to metolazone. The mean (±standard deviation) decrease in weight at 96 h was 3.0 (2.5) kg with dapagliflozin compared to 3.6 (2.0) kg with metolazone [mean difference 0.65, 95% confidence interval (CI) -0.12,1.41 kg; P = 0.11]. Loop diuretic efficiency was less with dapagliflozin than with metolazone [mean 0.15 (0.12) vs. 0.25 (0.19); difference -0.08, 95% CI -0.17,0.01 kg; P = 0.10]. Changes in pulmonary congestion and volume assessment score were similar between treatments. Decreases in plasma sodium and potassium and increases in urea and creatinine were smaller with dapagliflozin than with metolazone. Serious adverse events were similar between treatments.

CONCLUSION

In patients with heart failure and loop diuretic resistance, dapagliflozin was not more effective at relieving congestion than metolazone. Patients assigned to dapagliflozin received a larger cumulative dose of furosemide but experienced less biochemical upset than those assigned to metolazone.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04860011.

Etiology and Management of Edema: A Review

The development of peripheral edema can often pose a significant diagnostic and therapeutic challenge for practitioners due to its association with a wide variety of underlying disorders ranging in severity. Updates to the original Starling's principle have provided new mechanistic insights into edema formation. Additionally, contemporary data highlighting the role of hypochloremia in the development of diuretic resistance provide a possible new therapeutic target. This article reviews the pathophysiology of edema formation and discusses implications for treatment.

Effect of the combination of bumetanide plus chlorthalidone on hypertension and volume overload in patients with chronic kidney disease stage 4-5 KDIGO without renal replacement therapy: a double-blind randomized HEBE-CKD trial

Background

The co-administration of loop diuretics with thiazide diuretics is a therapeutic strategy in patients with hypertension and volume overload. The aim of this study was to assess the efficacy and safety of treatment with bumetanide plus chlorthalidone in patients with chronic kidney disease (CKD) stage 4–5 KDIGO.

Methods

A double-blind randomized study was conducted. Patients were randomized into two groups: bumetanide plus chlorthalidone group (intervention) and the bumetanide plus placebo group (control) to evaluate differences in TBW, ECW and ECW/TBW between baseline and 30 Days of follow-up. Volume overload was defined as ‘bioelectrical impedance analysis as fluid volume above the 90th percentile of a presumed healthy reference population. The study’s registration number was NCT03923933.

Results

Thirty-two patients with a mean age of 57.2 ± 9.34 years and a median estimated glomerular filtration rate (eGFR) of 16.7 ml/min/1.73 m² (2.2–29) were included. There was decreased volume overload in the liters of total body water (TBW) on Day 7 (intervention: -2.5 vs. control: -0.59, p = 0.003) and Day 30 (intervention: -5.3 vs. control: -0.07, p = 0.016); and in liters of extracellular water (ECW) on Day 7 (intervention: -1.58 vs. control: -0.43, p < 0.001) and Day 30 (intervention: -3.05 vs. control: -0.15, p < 0.000). There was also a decrease in systolic blood pressure on Day 7 (intervention: -18 vs. control: -7.5, p = 0.073) and Day 30 (intervention: -26.1 vs. control: -10, p = 0.028) and in diastolic blood pressure on Day 7 (intervention: -8.5 vs. control: -2.25, p = 0.059) and Day 30 (intervention: -13.5 vs. control: -3.4, p = 0.018).

Conclusion

In CKD stage 4–5 KDIGO without renal replacement therapy, bumetanide in combination with chlorthalidone is more effective in treating volume overload and hypertension than bumetanide with placebo.

Assessment of clinical and hemodynamic congestion as predictors of mortality in elderly outpatients with heart failure

INTRODUCTION

This work aims to evaluate whether a clinical examination and measurement of N-terminal pro-brain natriuretic peptide can predict poor prognosis in outpatients with heart failure.

PATIENTS AND METHODS

We carried out a retrospective study from 2010 to 2018 in 238 patients diagnosed with heart failure. At baseline, we evaluated the presence of pulmonary rales and bilateral leg edema (clinical congestion) together with N-terminal pro-brain natriuretic peptide ≥ 1500 pg/mL (hemodynamic congestion). Patients were classified into 4 groups depending on their congestion pattern: no congestion (G1) (n = 50); clinical congestion (G2) (n = 43); hemodynamic congestion (G3) (n = 73); and clinical and hemodynamic congestion (G4) (n = 72). The primary outcome was all-cause mortality at one year of follow-up.

RESULTS

A total of 238 patients were included. The mean age was 82 years, 61.8% were women, and 20.7% had reduced left ventricular ejection fraction. Thirty patients died in the first year of follow-up (12.6%). After controlling for confounding variables (sex, recent discharge for heart failure, estimated glomerular filtration rate, and left ventricular ejection fraction), the independent risk of death in each group compared to G1 as the reference group was: G2: HR 4.121 (95%CI 1.131-15.019); G3: HR 2.511 (95%CI 1.007-6.263); and G4: HR 7.418 (95%CI 1.630-33.763).

CONCLUSION

Congestion in outpatients with heart failure correlates with prognosis. Patients with both clinical and hemodynamic congestion had the highest risk of all-cause death at one year.

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.

Classic and Novel Mechanisms of Diuretic Resistance in Cardiorenal Syndrome

Despite the incompletely understood multiple etiologies and underlying mechanisms, cardiorenal syndrome is characterized by decreased glomerular filtration and sodium avidity. The underlying level of renal sodium avidity is of primary importance in driving a congested heart failure phenotype and ultimately determining the response to diuretic therapy. Historically, mechanisms of kidney sodium avidity and resultant diuretic resistance were primarily extrapolated to cardiorenal syndrome from non-heart failure populations. Yet, the mechanisms appear to differ between these populations. Recent literature in acute decompensated heart failure has refuted several classically accepted diuretic resistance mechanisms and reshaped how we conceptualize diuretic resistance mechanisms in cardiorenal syndrome. Herein, we propose an anatomically based categorization of diuretic resistance mechanisms to establish the relative importance of specific transporters and translate findings toward therapeutic strategies. Within this categorical structure, we discuss classic and novel mechanisms of diuretic resistance.

Impact of Loop Diuretic on Outcomes in Patients with Heart Failure and Reduced Ejection Fraction

PURPOSE OF REVIEW

Loop diuretics are the cornerstone of the treatment of congestion in heart failure patients. The manuscript aims to summarize the most updated information regarding the use of loop diuretics in heart failure.

RECENT FINDINGS

Diuretic response can be highly variable between patients and needs to be carefully evaluated during and after the hospitalization. Diuretic resistance can lead to residual congestion which affects prognosis and can be difficult to detect. The effect of loop diuretics on long-term prognosis remains uncertain but patients with advanced heart failure typically have renal dysfunction and are more inclined to develop loop diuretic resistance, which may lead to an incomplete decongestion and thus to a worse prognosis. Loop diuretics are the most potent diuretics available and their use is recommended in order to alleviate symptoms, improve exercise capacity, and reduce hospitalizations in patients with heart failure. Their use should be limited to the lowest dose necessary to maintain euvolemia because a low dose does not increase the risk of decompensation but reduce the risk of adverse effects and allow the up-titration of disease-modifying drugs.

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.

Compensatory post-diuretic renal sodium reabsorption is not a dominant mechanism of diuretic resistance in acute heart failure

AIMS

In healthy volunteers, the kidney deploys compensatory post-diuretic sodium reabsorption (CPDSR) following loop diuretic-induced natriuresis, minimizing sodium excretion and producing a neutral sodium balance. CPDSR is extrapolated to non-euvolemic populations as a diuretic resistance mechanism; however, its importance in acute decompensated heart failure (ADHF) is unknown.

METHODS AND RESULTS

Patients with ADHF in the Mechanisms of Diuretic Resistance cohort receiving intravenous loop diuretics (462 administrations in 285 patients) underwent supervised urine collections entailing an immediate pre-diuretic spot urine sample, then 6-h (diuretic-induced natriuresis period) and 18-h (post-diuretic period) urine collections. The average spot urine sodium concentration immediately prior to diuretic administration [median 15 h (13-17) after last diuretic] was 64 ± 33 mmol/L with only 4% of patients having low (<20 mmol/L) urine sodium consistent with CPDSR. Paradoxically, greater 6-h diuretic-induced natriuresis was associated with larger 18-h post-diuretic spontaneous natriuresis (r = 0.7, P < 0.001). Higher pre-diuretic urine sodium to creatinine ratio (r = 0.37, P < 0.001) was the strongest predictor of post-diuretic spontaneous natriuresis. In a subgroup of patients (n = 43) randomized to protocol-driven intensified diuretic therapies, the mean diuretic-induced natriuresis increased three-fold. In contrast to the substantial decrease in spontaneous natriuresis predicted by CPDSR, no change in post-diuretic spontaneous natriuresis was observed (P = 0.47).

CONCLUSION

On a population level, CPDSR was not an important driver of diuretic resistance in hypervolemic ADHF. Contrary to CPDSR, a greater diuretic-induced natriuresis predicted a larger post-diuretic spontaneous natriuresis. Basal sodium avidity, rather than diuretic-induced CPDSR, appears to be the predominant determinate of both diuretic-induced and post-diuretic natriuresis in hypervolemic ADHF.

Multinephron Segment Diuretic Therapy to Overcome Diuretic Resistance in Acute Heart Failure: A Single-Center Experience

BACKGROUND

The concept of multinephron segment diuretic therapy (MSDT) has been recommended in severe diuretic resistance with only expert opinion and case-level evidence. The purpose of this study was to investigate the safety and efficacy of MSDT, combining 4 diuretic classes, in acute heart failure (AHF) complicated by diuretic resistance.

METHODS AND RESULTS

A retrospective analysis was conducted in patients hospitalized with AHF at a single medical center who received MSDT, including concomitant carbonic anhydrase inhibitor, loop, thiazide, and mineralocorticoid receptor antagonist diuretics. Subjects served as their own controls with efficacy evaluated as urine output and weight change before and after MSDT. Serum chemistries, renal replacement therapies, and in-hospital mortality were evaluated for safety. Patients with severe diuretic resistance before MSDT were analyzed as a subcohort. A total of 167 patients with AHF and diuretic resistance received MSDT. MSDT was associated with increased median 24-hour urine output in the first day of therapy compared with the previous day (2.16 L [0.95-4.14 L] to 3.08 L [1.74-4.86 L], P = .003) in the total cohort and in the Severe diuretic resistance cohort (0.91 L [0.43-1.43 L] to 2.08 L [1.13-3.96 L], P < .001). The median cumulative weight loss at day 7 or discharge was -7.4 kg (-15.3 to -3.4 kg) (P = .02). Neither serum sodium, chloride, potassium, bicarbonate, or creatinine changed significantly relative to baseline (P > .05 for all).

CONCLUSIONS

In an AHF cohort with diuretic resistance, MSDT was associated with increased diuresis without changes in serum chemistries or kidney function. Prospective studies of MSDT in AHF and diuretic resistance are warranted.

Diuretic strategies in patients with resistance to loop-diuretics in the intensive care unit: A retrospective study from the MIMIC-III database

PURPOSE

To investigate various diuretic strategies to alleviate loop-diuretics resistance in critically ill patients.

MATERIALS AND METHOD

ICU adults requiring more than 1 mg/kg/day of furosemide, from the MIMIC-III database. Four diuretic strategies were investigated: incremental dose of loop diuretics, continuous infusion, combinations with a second class of diuretics and administration of intravenous albumin. A generalized estimating equation was used to investigate the associations between these strategies and endpoints. The primary outcome was the 24-h urine output and secondary endpoints included fluid balance, weight change, electrolyte and acid-base abnormalities, kidney replacement therapy initiation, and mortality.

RESULTS

A total of 7645 ICU stays from 6358 patients were included. After adjustment, the use of continuous loop-diuretic infusion was associated with a higher 24-h urine output (β: 732, 95% CI:669-795, p < 0.001), lower 24-h fluid balance (p < 0.001) and greater weight loss at 48-h (p < 0.001). Thiazide- and carbonic anhydrase inhibitor combinations were both associated with higher urine output (p < 0.001) and weight loss at 48-h (p < 0.01), while intravenous albumin was associated with fluid gain (p < 0.001). Risks of electrolyte and metabolic disturbances varied across diuretic strategies.

CONCLUSIONS

Continuous loop-diuretic infusion and thiazide- or acetazolamide-loop diuretic combinations increased urine output significantly, leading to a negative fluid balance and weight loss.

Efficacy and safety of dapagliflozin in acute heart failure: Rationale and design of the DICTATE-AHF trial

BACKGROUND

Dapagliflozin, a sodium-glucose cotransporter-2 inhibitor, reduces cardiovascular death and worsening heart failure in patients with chronic heart failure and reduced ejection fraction. Early initiation during an acute heart failure (AHF) hospitalization may facilitate decongestion, improve natriuresis, and facilitate safe transition to a beneficial outpatient therapy for both diabetes and heart failure.

OBJECTIVE

The objective is to assess the efficacy and safety of initiating dapagliflozin within the first 24 hours of hospitalization in patients with AHF compared to usual care.

METHODS

DICTATE-AHF is a prospective, multicenter, open-label, randomized trial enrolling a planned 240 patients in the United States. Patients with type 2 diabetes hospitalized with hypervolemic AHF and an estimated glomerular filtration rate of at least 30 mL/min/1.73m² are eligible for participation. Patients are randomly assigned 1:1 to dapagliflozin 10 mg once daily or structured usual care until day 5 or hospital discharge. Both treatment arms receive protocolized diuretic and insulin therapies. The primary endpoint is diuretic response expressed as the cumulative change in weight per cumulative loop diuretic dose in 40 mg intravenous furosemide equivalents. Secondary and exploratory endpoints include inpatient worsening AHF, 30-day hospital readmission for AHF or diabetic reasons, change in NT-proBNP, and measures of natriuresis. Safety endpoints include the incidence of hyper/hypoglycemia, ketoacidosis, worsening kidney function, hypovolemic hypotension, and inpatient mortality.

CONCLUSIONS

The DICTATE-AHF trial will establish the efficacy and safety of early initiation of dapagliflozin during AHF across both AHF and diabetic outcomes in patients with diabetes.

[The use of diuretics in chronic heart failure. Position paper of the Russian Heart Failure Society]

The document focuses on key issues of diuretic therapy in CHF from the standpoint of current views on the pathogenesis of edema syndrome, its diagnosis, and characteristics of using diuretics in various clinical situations.

Improving Global Healthcare and Reducing Costs Using Second-Generation Artificial Intelligence-Based Digital Pills: A Market Disruptor

Background and Aims: Improving global health requires making current and future drugs more effective and affordable. While healthcare systems around the world are faced with increasing costs, branded and generic drug companies are facing the challenge of creating market differentiators. Two of the problems associated with the partial or complete loss of response to chronic medications are a lack of adherence and compensatory responses to chronic drug administration, which leads to tolerance and loss of effectiveness. Approach and Results: First-generation artificial intelligence (AI) systems do not address these needs and suffer from a low adoption rate by patients and clinicians. Second-generation AI systems are focused on a single subject and on improving patients' clinical outcomes. The digital pill, which combines a personalized second-generation AI system with a branded or generic drug, improves the patient response to drugs by increasing adherence and overcoming the loss of response to chronic medications. By improving the effectiveness of drugs, the digital pill reduces healthcare costs and increases end-user adoption. The digital pill also provides a market differentiator for branded and generic drug companies. Conclusions: Implementing the use of a digital pill is expected to reduce healthcare costs, providing advantages for all the players in the healthcare system including patients, clinicians, healthcare authorities, insurance companies, and drug manufacturers. The described business model for the digital pill is based on distributing the savings across all stakeholders, thereby enabling improved global health.

Mechanisms of Diuretic Resistance Study: design and rationale

INTRODUCTION

Diuretic resistance is a common complication impairing decongestion during hospitalization for acute decompensated heart failure (ADHF). The current understanding of diuretic resistance mechanisms in ADHF is based upon extrapolations from other disease states and healthy volunteers. However, accumulating evidence suggests that the dominant mechanisms in other populations have limited influence on diuretic response in ADHF. Additionally, the ability to rapidly and reliably diagnose diuretic resistance is inadequate using currently available tools.

AIMS

The Mechanisms of Diuretic Resistance (MDR) Study is designed to rigorously investigate the mechanisms of diuretic resistance and develop tools to rapidly predict diuretic response in a prospective cohort hospitalized with ADHF.

METHODS

Study assessments occur serially during the ADHF hospitalization and after discharge. Each assessment includes a supervised 6-hour urine collection with baseline blood and timed spot urine collections following loop diuretic administration. Patient characteristics, medications, physical exam findings, and both in-hospital and post-discharge HF outcomes are collected. Patients with diuretic resistance are eligible for a randomized sub-study comparing an increased loop diuretic dose with combination diuretic therapy of loop diuretic plus chlorothiazide.

CONCLUSIONS

The Mechanisms of Diuretic Resistance Study will establish a prospective patient cohort and biorepository to investigate the mechanisms of diuretic resistance and urine biomarkers to rapidly predict loop diuretic resistance.

A Systematic Review and Meta-Analysis of Metolazone Compared to Chlorothiazide for Treatment of Acute Decompensated Heart Failure

Treatment of volume overload in the setting of acute decompensated heart failure (ADHF) is typically achieved through the use of loop diuretics. While they are highly effective, some patients may develop loop diuretic resistance. One strategy to overcome this scenario includes sequential nephron blockade with a thiazide-type diuretic; however, it is unknown which thiazide-type diuretic used in this setting is most effective. A systematic review and meta-analysis were performed to compare the efficacy and safety of chlorothiazide with metolazone as add-on therapy in the setting of loop diuretic resistance for the treatment of ADHF. Literature searches were conducted through PubMed, Google Scholar, and Science Direct from inception through February 2020 using the following search terms alone or in combination: metolazone, chlorothiazide, acute decompensated heart failure, loop diuretic, and urine output. All English-language prospective and retrospective trials and abstracts comparing metolazone to chlorothiazide for the treatment of ADHF were evaluated. Studies were included if they analyzed urine output for at least 24 hours in patients with ADHF. Meta-analysis was conducted to evaluate pooled effect size by using a random-effect model. Primary outcomes included net and total urine output. Secondary outcomes included commonly reported safety outcomes. Four studies comparing the use of metolazone to chlorothiazide as an adjunct to loop diuretics to treat ADHF were included in the evaluation. Metolazone was as effective as chlorothiazide to augment loop diuretic therapy in ADHF in most studies with no pooled difference in net or total urine output. However, there were notable differences in baseline loop diuretic dosing, ejection fraction, renal function, race, and endpoint timing across studies. Adverse effects were commonly observed and included electrolyte abnormalities, change in renal function, and hypotension but were comparable between groups. Metolazone is as effective as chlorothiazide as add-on to loop diuretics in treating ADHF without an increase in safety concerns.