Worsening renal function in acute heart failure in the context of diuretic response

Full decongestion in acute heart failure therapy

Incomplete decongestion is the main cause of readmission in the early post-discharge period of a hospitalization for acute heart failure. Recent heart failure guidelines have highlighted initiation and rapid up-titration of quadruple therapy with angiotensin receptor neprilysin inhibitor, beta adrenergic receptor blocker, mineralocorticoid receptor antagonist, and sodium glucose cotransporter 2 inhibitor to prevent hospitalizations for heart failure with reduced ejection fraction. However, full decongestion remains the foremost therapeutic goal of hospitalization for heart failure. While early addition of sodium glucose cotransporter 2 inhibitors and mineralocorticoid receptor antagonists may be helpful, the value of the other therapeutics comes after decongestion is complete.

Renal function and natriuresis-guided diuretic therapy - a pre-specified analysis from the PUSH-AHF trial

AIM

In a randomized controlled trial, we recently showed that a natriuresis-guided diuretic approach improved natriuresis and diuresis in patients with acute heart failure (HF). In this pre-specified analysis, we investigated the association between (worsening) renal function, outcomes and the effect of intensive natriuresis-guided loop diuretic therapy as compared with standard of care.

METHODS AND RESULTS

The Pragmatic Urinary Sodium-based algoritHm in Acute Heart Failure (PUSH-AHF) trial randomized patients to natriuresis-guided diuretic therapy or standard of care. Serum creatinine and estimated glomerular filtration rate (eGFR) were assessed at fixed timepoints, and worsening renal function (WRF) was assessed at 72 h. The primary outcome was the interaction between randomized treatment allocation, baseline eGFR and the dual primary outcome of PUSH-AHF: total natriuresis at 24 h and time to all-cause mortality or HF rehospitalization at 180 days. In 309 patients, median baseline eGFR was 53 (35-73) ml/min/1.73 m2, and 58% had eGFR <60 ml/min/1.73 m2. Baseline eGFR did not significantly modify the treatment effect of natriuresis-guided diuretic therapy on natriuresis at 24 h (p for interaction = 0.730). However, baseline eGFR significantly modified the effect on all-cause mortality and HF rehospitalization (p for interaction = 0.017): the risk of this second primary outcome was lower in patients with lower eGFR who were randomized to the natriuresis-guided group. In the natriuresis-guided arm, eGFR decreased more (-11.0 vs. -6.91 ml/min/1.73 m2; p = 0.002) during the first 3 days, but this effect was attenuated at discharge (-10.3 vs. -8.69 ml/min/1.73 m2; p = 0.38). WRF was more frequently observed in patients randomized to natriuresis-guided treatment, but was not associated with worse clinical outcomes.

CONCLUSIONS

Natriuresis-guided diuretic treatment improved diuresis and natriuresis irrespective of baseline eGFR and occurrence of WRF, was effective even in patients with low eGFR, and the observed effect on eGFR was transient and not associated with worse clinical outcomes.

Safety Indicators in Patients Receiving High-intensity Care After Hospital Admission for Acute Heart Failure: The STRONG-HF Trial

BACKGROUND

Safety, Tolerability and Efficacy of Rapid Optimization, Helped by NT-proBNP Testing, of Heart Failure Therapies (STRONG-HF) demonstrated the safety and efficacy of rapid up-titration of guideline-directed medical therapy (GDMT) with high-intensity care (HIC) compared with usual care in patients hospitalized for acute heart failure (HF). In the HIC group, the following safety indicators were used to guide up-titration: estimated glomerular filtration rate of <30 mL/min/1.73 m2, serum potassium of >5.0 mmol/L, systolic blood pressure (SBP) of <95 mmHg, heart rate of <55 bpm, and N-terminal pro-B-type natriuretic peptide concentration of >10% higher than predischarge values.

METHODS AND RESULTS

We examined the impact of protocol-specified safety indicators on achieved dose of GDMT and clinical outcomes. Three hundred thirteen of the 542 patients in the HIC arm (57.7%) met ≥1 safety indicator at any follow-up visit 1-6 weeks after discharge. As compared with those without, patients meeting ≥1 safety indicator had more severe HF symptoms, lower SBP, and higher heart rate at baseline and achieved a lower average percentage of GDMT optimal doses (mean difference vs the HIC arm patients not reaching any safety indicator, -11.0% [95% confidence interval [CI] -13.6 to -8.4%], P < .001). The primary end point of 180-day all-cause death or HF readmission occurred in 15.0% of patients with any safety indicator vs 14.2% of those without (adjusted hazard ratio 0.84, 95% CI 0.48-1.46, P = .540). None of each of the safety indicators, considered alone, was significantly associated with the primary end point, but an SBP of <95 mm Hg was associated with a trend toward increased 180-day all-cause mortality (adjusted hazard ratio 2.68, 95% CI 0.94-7.64, P = .065) and estimated glomerular filtration rate decreased to <30 mL/min/1.73 m2 with more HF readmissions (adjusted hazard ratio 3.60, 95% CI 1.22-10.60, P = .0203). The occurrence of a safety indicator was associated with a smaller 90-day improvement in the EURO-QoL 5-Dimension visual analog scale (adjusted mean difference -3.32 points, 95% CI -5.97 to -0.66, P = .015).

CONCLUSIONS

Among patients with acute HF enrolled in STRONG-HF in the HIC arm, the occurrence of any safety indicator was associated with the administration of slightly lower GDMT doses and less improvement in quality of life, but with no significant increase in the primary outcome of 180-day HF readmission or death when appropriately addressed according to the study protocol.

Renal function modifies the association between hemoconcentration and outcomes in hospitalized heart failure patients

Evidence-based management of decongestion is lacking in hospitalized heart failure (HHF) patients, especially in patients with impaired renal function. Hemoconcentration is an objective measure of decongestion that portends a favorable prognosis and guides management in HHF patients with preserved renal function. We aim to investigate whether it remains a prognosticator in patients with renal impairment, and to refine the identification of subpopulations who will benefit from hemoconcentration-guided therapy. HHF patients admitted to Heart Failure Center of Fuwai Hospital were consecutively included from December 2006 to June 2018. Patient characteristics were depicted. Relationships between in-hospital hemoconcentration, worsening renal function (WRF), and one-year all-cause mortality were investigated in the total population and compared between renal function groups using survival analysis and cubic splines, with a special focus on renal function-based interactions. The association was further validated in sensitivity analyses. Clinically relevant cut-offs and subpopulations were identified by subpopulation treatment effect pattern plots (STEPP) and subgroup analysis. 3661 participants (30.4% with impaired renal function) were included. Hemoconcentration, reflected by an in-hospital increase in hemoglobin, hematocrit, or a relative reduction in estimated plasma volume from baseline to discharge, was predictive of decreased one-year mortality in the total cohort despite its correlation with higher WRF incidence. The prognostic value of hemoconcentration differed in patients with impaired and preserved renal function. Hemoconcentration was related to a favorable prognosis in patients with preserved renal function (HR, 0.69; 95% CI, 0.53-0.90; P = 0.007), especially in young male patients with New York Heart Association functional class III-IV, reduced ejection fraction, and baseline eGFR > 75 mL/min/1.73m2. Contrarily, impaired renal function patients experienced a higher incidence of WRF, and hemoconcentration was no longer related to outcome (HR, 0.90; 95% CI, 0.64-1.26; P = 0.545), with findings consistent in all clinically relevant subgroups. In HHF patients, the prognostic value of hemoconcentration differs by renal function, and the clinical utility of hemoconcentration is contingent on preserved renal function.

Intrarenal Venous Flow Pattern Changes Do Relate With Renal Function Alterations in Acute Heart Failure

BACKGROUND

There is scarce evidence supporting the clinical utility of congestive intrarenal venous flow (IRVF) patterns in patients with acute heart failure.

OBJECTIVES

This study aims to: 1) investigate the association between IRVF patterns and the odds of worsening renal function (WRF); 2) track the longitudinal changes of serum creatinine (sCr) across IRVF at predetermined points and its association with decongestion; and 3) explore the relationship between IRVF/WRF categories and patient outcomes.

METHODS

IRVF was assessed at baseline (pre-decongestive therapy), 72 hours, and 30 and 90 days postdischarge. Changes in sCr trajectories across dynamic IRVF variations and parameters of decongestion were assessed using linear mixed effect models. The association between IRVF/WRF categories and outcomes was evaluated using univariable/multivariable models.

RESULTS

In this prospective, multicenter study with 188 participants, discontinuous IRVF patterns indicated higher odds of WRF (OR: 3.90 [95% CI: 1.24-12.20]; P = 0.020 at 72 hours; and OR: 5.76 [95% CI: 1.67-19.86]; P = 0.006 at 30 days) and an increase in sCr (Δ-72 hours 0.14 mg/dL [95% CI: 0.06-0.22]; P = 0.001; Δ-discharge 0.13 mg/dL [95% CI: 0.03-0.23]; P = 0.007). However, the diuretic response and decongestion significantly influenced the magnitude of these changes. Patients exhibiting both WRF and discontinuous IRVF at 30 days experienced an increased hazard of adverse events (HR: 5.96 [95% CI: 2.63-13.52]; P < 0.001).

CONCLUSIONS

Discontinuous IRVF identifies patients with higher odds of WRF during admission and postdischarge periods. Nonetheless, adequate diuretic response and decongestion could modify this association. Patients showing both WRF and discontinuous IRVF at 30 days had increased rates of adverse events.

Clinical Review of Hypertensive Acute Heart Failure

Although acute heart failure (AHF) is a common disease associated with significant symptoms, morbidity and mortality, the diagnosis, risk stratification and treatment of patients with hypertensive acute heart failure (H-AHF) still remain a challenge in modern medicine. Despite great progress in diagnostic and therapeutic modalities, this disease is still accompanied by a high rate of both in-hospital (from 3.8% to 11%) and one-year (from 20% to 36%) mortality. Considering the high rate of rehospitalization (22% to 30% in the first three months), the treatment of this disease represents a major financial blow to the health system of each country. This disease is characterized by heterogeneity in precipitating factors, clinical presentation, therapeutic modalities and prognosis. Since heart decompensation usually occurs quickly (within a few hours) in patients with H-AHF, establishing a rapid diagnosis is of vital importance. In addition to establishing the diagnosis of heart failure itself, it is necessary to see the underlying cause that led to it, especially if it is de novo heart failure. Given that hypertension is a precipitating factor of AHF and in up to 11% of AHF patients, strict control of arterial blood pressure is necessary until target values are reached in order to prevent the occurrence of H-AHF, which is still accompanied by a high rate of both early and long-term mortality.

Patient-Centered Heart Failure Therapy

Simultaneous initiation of quadruple therapy with angiotensin receptor-neprilysin inhibitor, beta-adrenergic receptor blocker, mineralocorticoid receptor antagonist, and sodium glucose cotransporter 2 inhibitor aims at prompt improvement and prevention of readmission in patients hospitalized for heart failure with reduced ejection fraction. However, titration of quadruple therapy is time consuming. Lengthy up-titration of quadruple therapy may negate the benefit of early initiation. Quadruple therapy should start with a sodium glucose cotransporter 2 inhibition and a mineralocorticoid antagonist, as both enable safe decongestion and require minimal or no titration. Depending on the level of decongestion and clinical characteristics, patients receive an angiotensin receptor-neprilysin inhibitor or a beta-adrenergic receptor blocker to be titrated after hospital discharge. Outpatient addition of an angiotensin receptor-neprilysin inhibitor to a beta-adrenergic receptor blocker or vice versa completes the quadruple therapy scheme. By focusing on decongestion and matching intervention to patients' profile, the present therapeutic sequence allows rapid implementation of quadruple therapy at fully recommended doses.

Combining loop and thiazide diuretics for acute heart failure across the estimated glomerular filtration rate spectrum: A post-hoc analysis of the CLOROTIC trial

AIMS

In patients with acute heart failure (AHF), the addition of hydrochlorothiazide (HCTZ) to furosemide improved diuretic response in the CLOROTIC trial. This work aimed to evaluate if these effects differ across the estimated glomerular filtration rate (eGFR) spectrum.

METHODS AND RESULTS

This post-hoc analysis of the CLOROTIC trial analysed 230 patients with AHF and explored the influence of eGFR on primary and secondary endpoints. The median eGFR was 43 ml/min/1.73 m2 (range 14-109) and 23% had eGFR ≥60 ml/min/1.73 m2 (group 1), 24% from 45 to 59 ml/min/1.73 m2 (group 2), and 53% <45 ml/min/1.73 m2 (group 3). Patients treated with HCTZ had greatest weight loss at 72 h in all three groups, but patients in group 1 had a significantly greater response (-2.1 kg [-3.0 to 0.5]), compared to patients in groups 2 (-1.3 kg [-2.3 to 0.2]) and 3 (-0.1 kg [-1.3 to 0.4]) (p-value for interaction = 0.246). At 96 h, the differences in weight were -1.8 kg (-3.0 to -0.3), -1.4 kg (-2.6 to 0.3), and -0.5 kg (-1.3 to -0.1) in groups 1, 2, and 3, respectively (p-value for interaction = 0.256). There were no significant differences observed with the addition of HCTZ in terms of diuretic response, mortality or rehospitalizations, or safety endpoints (impaired renal function, hyponatraemia, and hypokalaemia) among the three eGFR groups (all p-values for interaction were no significant).

CONCLUSION

The addition of eGFR-adjusted doses of oral HCTZ to loop diuretics in patients with AHF improved diuretic response across the eGFR spectrum.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov: NCT01647932; EudraCT number: 2013-001852-36.

Early glomerular filtration rate decline is associated with hemoglobin rise following dapagliflozin initiation in heart failure with reduced ejection fraction

INTRODUCTION AND OBJECTIVES

Sodium-glucose cotransporter-2 inhibitors (SGLT2i) induce short-term changes in renal function and hemoglobin. Their pathophysiology is incompletely understood. We aimed to evaluate the relationship between 1- and 3-month estimated glomerular filtration rate (eGFR) and hemoglobin changes following initiation of dapagliflozin in patients with stable heart failure with reduced ejection fraction (HFrEF).

METHODS

This is a post hoc analysis of a randomized clinical trial that evaluated the effect of dapagliflozin on 1- and 3-month peak oxygen consumption in outpatients with stable HFrEF (DAPA-VO2 trial, NCT04197635). We used linear mixed regression analysis to assess the relationship between eGFR and hemoglobin changes across treatment arms.

RESULTS

A total of 87 patients were evaluated in this substudy. The mean age was 67.0± 10.5 years, and 21 (24.1%) were women. The mean baseline eGFR and hemoglobin were 66.9±20.7mL/min/1.73m2 and 14.3±1.7g/dL, respectively. Compared with placebo, eGFR did not significantly change at either time points in the dapagliflozin group, but hemoglobin significantly increased at 1 and 3 months. At 1 month, the hemoglobin increase was related to decreases in eGFR only in the dapagliflozin arm (P <.001). At 3 months, there was no significant association in either treatment arms (P=.123). Changes in eGFR were not associated with changes in peak oxygen consumption, quality of life, or natriuretic peptides.

CONCLUSIONS

In patients with stable HFrEF, 1-month changes in eGFR induced by dapagliflozin are inversely related to changes in hemoglobin. This association was no longer significant at 3 months.

Emerging Individualized Approaches in the Management of Acute Cardiorenal Syndrome With Renal Assist Devices

Growing insights into the pathophysiology of acute cardiorenal syndrome (CRS) in acute decompensated heart failure have indicated that not every rise in creatinine is associated with adverse outcomes. Detection of persistent volume overload and diuretic resistance associated with creatinine rise may identify patients with true acute CRS. More in-depth phenotyping is needed to identify pathologic processes in renal arterial perfusion, venous outflow, and microcirculatory-interstitial-lymphatic axis alterations that can contribute to acute CRS. Recently, various novel device-based interventions designed to target different pathophysiologic components of acute CRS are in early feasibility and proof-of-concept studies. However, appropriate trial endpoints that reflect improvement in cardiorenal trajectories remain elusive and highly debated. In this review the authors describe the variety of physiological derangements leading to acute CRS and the opportunity to individualize the management of acute CRS with novel renal assist devices that can target specific components of these alterations.

Renal function and decongestion with acetazolamide in acute decompensated heart failure: the ADVOR trial

BACKGROUND AND AIMS

In the ADVOR trial, acetazolamide improved decongestion in acute decompensated heart failure (ADHF). Whether the beneficial effects of acetazolamide are consistent across the entire range of renal function remains unclear.

METHODS

This is a pre-specified analysis of the ADVOR trial that randomized 519 patients with ADHF to intravenous acetazolamide or matching placebo on top of intravenous loop diuretics. The main endpoints of decongestion, diuresis, natriuresis, and clinical outcomes are assessed according to baseline renal function. Changes in renal function are evaluated between treatment arms.

RESULTS

On admission, median estimated glomerular filtration rate (eGFR) was 40 (30-52) mL/min/1.73 m². Acetazolamide consistently increased the likelihood of decongestion across the entire spectrum of eGFR (P-interaction = .977). Overall, natriuresis and diuresis were higher with acetazolamide, with a higher treatment effect for patients with low eGFR (both P-interaction < .007). Acetazolamide was associated with a higher incidence of worsening renal function (WRF; rise in creatinine ≥ 0.3 mg/dL) during the treatment period (40.5% vs. 18.9%; P < .001), but there was no difference in creatinine after 3 months (P = .565). This was not associated with a higher incidence of heart failure hospitalizations and mortality (P-interaction = .467). However, decongestion at discharge was associated with a lower incidence of adverse clinical outcomes irrespective of the onset of WRF (P-interaction = .805).

CONCLUSIONS

Acetazolamide is associated with a higher rate of successful decongestion across the entire range of renal function with more pronounced effects regarding natriuresis and diuresis in patients with a lower eGFR. While WRF occurred more frequently with acetazolamide, this was not associated with adverse clinical outcomes.

CLINICALTRIALS.GOV IDENTIFIER

NCT03505788.

Kidney function changes in acute heart failure: a practical approach to interpretation and management

Worsening kidney function (WKF) is common in patients with acute heart failure (AHF) syndromes. Although WKF has traditionally been associated with worse outcomes on a population level, serum creatinine concentrations vary greatly during episodes of worsening heart failure, with substantial individual heterogeneity in terms of their clinical meaning. Consequently, interpreting such changes within the appropriate clinical context is essential to unravel the pathophysiology of kidney function changes and appropriately interpret their clinical meaning. This article aims to provide a critical overview of WKF in AHF, aiming to provide physicians with some tips and tricks to appropriately interpret kidney function changes in the context of AHF.

Worsening renal function in hospitalized patients with systolic heart failure: prevalence and risk factors

AIMS

Heart failure (HF) is usually associated with complications of other organs. Renal impairment is seen in a significant proportion of HF patients and is characterized by worsening renal function (WRF). WRF can be used for predicting symptom exacerbation in systolic HF. This study aimed to determine the prevalence and risk factors of WRF among hospitalized patients with systolic HF.

METHODS AND RESULTS

In this cross-sectional study, data from medical records of 347 hospitalized patients diagnosed with HFrEF from 2019 to 2020, admitted to Tabriz Shahid Madani Heart Hospital, who met the predefined inclusion criteria, were retrieved. Patients were divided into two groups based on the in-hospital occurrence of WRF. Laboratory tests and para-clinical findings were collected and analysed using SPSS Version 20.0. Statistical significance was accepted at a P value of <0.05. In this study, 347 hospitalized patients with HFrEF were included. The mean (standard deviation) age was 62.34 (±18.87) years. The mean (SD) length of stay was 6.34 (±4) days. According to our findings, 117 patients (33.71%) had WRF. Following multivariate analysis of potential predictors of WRF occurrence, hyponatremia, haemoglobin concentration, white blood cell count and prior diuretic use were found to be independent predictors for WRF occurrence in patients with systolic heart failure.

CONCLUSIONS

This study revealed that in patients with WRF, mortality rate and length of stay were significantly greater than those of patients without WRF. Initial clinical characteristics of HF patients who developed WRF can help physicians identify patients with a higher risk of WRF.

Early glomerular filtration rates changes and risk of mortality in acute heart failure. The modifying role of admission renal function and decongestion

BACKGROUND

The pathophysiology of changes in estimated glomerular filtration rate (eGFR) in acute heart failure (AHF) is complex and multifactorial. We evaluated the associated mortality risk of early changes in eGFR across baseline renal function on admission and early changes in natriuretic peptides in patients admitted with AHF.

METHODS

We retrospectively evaluated 2,070 patients admitted with AHF. Renal dysfunction on admission was defined as eGFR<60 ml/min/1.73m2 and successful decongestion as NT-proBNP decreased >30% from baseline. We assessed the mortality risk associated with eGFR changes from baseline at 48-72 h after admission (ΔeGFR%) according to baseline renal function, and NT-proBNP changes at 48-72 h through Cox regression analyses.

RESULTS

The mean age was 74.4 ± 11.2 years, and 930 (44.9%) were women. The proportion of admission eGFR<60 ml/min/1.73m2 and 48-72 h changes in NT-proBNP>30% were 50.5% and 32.8%, respectively. At a median follow-up of 1.75 years, 928 deaths were registered. In the whole sample, changes in renal function were not associated with mortality (p = 0.208). The adjusted analysis revealed that the risk of mortality related to ΔeGFR% was heterogeneous across baseline renal function and changes in NT-proBNP (p-value for interaction=0.003). ΔeGFR% was not associated with mortality in patients with baseline eGFR≥60 ml/min/1.73m2. In those with eGFR<60 ml/min/1.73m2, a decrease in eGFR was associated with higher mortality, particularly in those with a reduction in NT-proBNP<30%.

CONCLUSION

In patients with AHF, early ΔeGFR% was associated with the risk of long-term mortality only in patients with renal dysfunction on admission and no early decline in NT-proBNP.

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.

Recent Developments in the Evaluation and Management of Cardiorenal Syndrome: A Comprehensive Review

Cardiorenal syndrome (CRS) is an increasingly recognized diagnostic entity associated with high morbidity and mortality among acutely ill heart failure (HF) patients with acute and/ or chronic kidney diseases (CKD). While traditionally viewed as a state of decline in glomerular filtration rate (GFR) due to decreased renal perfusion, mainly due to therapeutic interventions to relieve congestive in HF, recent insights into the underlying pathophysiologic mechanisms of CRS led to a broader definition and further classification of CRS into 5 distinct types. In this comprehensive review, we discuss the classification of CRS, highlighting the underlying common pathogenetic pathways of heart failure and kidney injury, including increased congestion, neurohormonal dysregulation, oxidative stress as well as inflammation, and cytokine storm that are particularly evident in COVID-19 patients with multiorgan failure and also in those with other disorders including sepsis, systemic lupus erythematosus and amyloidosis. In this review we also present the recent advances in the diagnostic strategies of CRS including cardiac and renal biomarkers as well as advanced cardiac and renal imaging techniques that are available to aid in the diagnosis as well as in the prognostication of this disorder. Finally, we discuss the various therapeutic options available to-date, including fluid optimization, hemofiltration, renal replacement therapy as well as the role of SGLT2 inhibitors in light of recent data from RCTs. It is important to note that, CRS population are either excluded or underrepresented, at best, in major RCTs and therefore, therapeutic recommendations are largely extrapolated from HF and CKD clinical trials.

Combining loop with thiazide diuretics for decompensated heart failure: the CLOROTIC trial

AIMS

To evaluate whether the addition of hydrochlorothiazide (HCTZ) to intravenous furosemide is a safe and effective strategy for improving diuretic response in acute heart failure (AHF).

METHODS AND RESULTS

A prospective, double-blind, placebo-controlled trial, including patients with AHF randomized to receive HCTZ or placebo in addition to an intravenous furosemide regimen. The coprimary endpoints were changes in body weight and patient-reported dyspnoea 72 h after randomization. Secondary outcomes included metrics of diuretic response and mortality/rehospitalizations at 30 and 90 days. Safety outcomes (changes in renal function and/or electrolytes) were also assessed. Two hundred and thirty patients (48 women, 83 years) were randomized. Patients assigned to HCTZ were more likely to lose weight at 72 h than those assigned to placebo [2.3 vs. 1.5 kg; adjusted estimated difference (notionally 95 confidence interval) 1.14 (1.84 to 0.42); P 0.002], but there were no significant differences in patient-reported dyspnoea (area under the curve for visual analogue scale: 960 vs. 720; P 0.497). These results were similar 96 h after randomization. Patients allocated to HCTZ showed greater 24 h diuresis (1775 vs. 1400 mL; P 0.05) and weight loss for each 40 mg of furosemide (at 72 and at 96 h) (P 0.001). Patients assigned to HCTZ more frequently presented impaired renal function (increase in creatinine 26.5 moL/L or decrease in eGFR 50; 46.5 vs. 17.2; P 0.001), but hypokalaemia and hypokalaemia were similar between groups. There were no differences in mortality or rehospitalizations.

CONCLUSION

The addition of HCTZ to loop diuretic therapy improved diuretic response in patients with AHF.

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.

SGLT2 inhibitors in the treatment of type 2 cardiorenal syndrome: Focus on renal tubules

The pathogenesis of type 2 cardiorenal syndrome (CRS) is mostly associated with reduced cardiac output, increased central venous pressure (CVP), activation of the renin-angiotensin-aldosterone system (RAAS), inflammation, and oxidative stress. As a drug to treat diabetes, sodium-glucose transporter 2 inhibitor (SGLT2i) has been gradually found to have a protective effect on the heart and kidney and has a certain therapeutic effect on CRS. In the process of chronic heart failure (CHF) leading to chronic renal insufficiency, the renal tubular system, as the main functional part of the kidney, is the first to be damaged, but this damage can be reversed. In this review, we focus on the protective mechanisms of SGLT2i targeting renal tubular in the treatment of CRS, including natriuresis and diuresis to relieve renal congestion, attenuate renal tubular fibrosis, improve energy metabolism of renal tubular, and slow tubular inflammation and oxidative stress. This may have beneficial effects on the treatment of CRS and is a direction for future research.

How to interpret serum creatinine increases during decongestion

During decongestion in acute decompensated heart failure (ADHF), it is common to observe elevations in serum creatinine (sCr) values due to vascular congestion, a mechanism that involves increased central venous pressure that has a negative impact on the nephron, promoting greater absorption of water and sodium, increased interstitial pressure in an encapsulated organ developing "renal tamponade" which is one of main physiopathological mechanism associated with impaired kidney function. For the treatment of this syndrome, it is recommended to use diuretics that generate a high urinary output and natriuresis to decongest the venous system, during this process the sCr values can rise, a phenomenon that may bother some cardiologist and nephrologist, since raise the suspicion of kidney damage that could worsen the prognosis of these patients. It is recommended that increases of up to 0.5 mg/dL from baseline are acceptable, but some patients have higher increases, and we believe that an arbitrary number would be impractical for everyone. These increases in sCr may be related to changes in glomerular hemodynamics and true hypovolemia associated with decongestion, but it is unlikely that they are due to structural injury or truly hypoperfusion and may even have a positive connotation if accompanied by an effective decongestion and be associated with a better prognosis in the medium to long term with fewer major cardiovascular and renal events. In this review, we give a comprehensive point of view on the interpretation of creatinine elevation during decongestion in patients with ADHF.

Renal effects of empagliflozin in patients hospitalized for acute heart failure: from the EMPULSE trial

AIM

The sodium-glucose cotransporter 2 (SGLT2) inhibitor empagliflozin improved clinical outcomes in patients hospitalized for acute heart failure. In patients with chronic heart failure, SGLT2 inhibitors cause an early decline in estimated glomerular filtration rate (eGFR) followed by a slower eGFR decline over time than placebo. However, the effects of SGLT2 inhibitors on renal function during a hospital admission for acute heart failure remain largely unknown.

METHODS AND RESULTS

Between 1 and 5 days after a hospitalization for acute heart failure, 530 patients with an eGFR >20 ml/min/1.73 m² were randomized to 10 mg of empagliflozin or placebo and treated for 90 days. Renal function and electrolytes were measured at baseline, and after 15, 30 and 90 days. We evaluated the effect of empagliflozin on eGFR over time and the impact of baseline eGFR on the primary hierarchical outcome of death, worsening heart failure events and quality of life. Mean baseline eGFR was 52.4 ml/min/1.73 m² in the empagliflozin group and 55.7 ml/min/1.73 m² in the placebo group. Empagliflozin caused an initial decline in eGFR (-2 ml/min/1.73 m² at day 15 compared to placebo). At day 90, eGFR was similar between empagliflozin and placebo. Investigator-reported acute renal failure occurred in 7.7% of empagliflozin versus 12.1% of placebo patients. The overall clinical benefit (hierarchical composite of all-cause death, heart failure events and quality of life) of empagliflozin was unaffected by baseline eGFR.

CONCLUSION

In patients hospitalized for acute heart failure, empagliflozin caused an early modest decline in renal function which was no longer evident after 90 days. Acute renal events were similar in both groups. The clinical benefit of empagliflozin was consistent regardless of baseline renal function.

Congestion in heart failure: a circulating biomarker-based perspective. A review from the Biomarkers Working Group of the Heart Failure Association, European Society of Cardiology

Congestion is a cardinal sign of heart failure (HF). In the past, it was seen as a homogeneous epiphenomenon that identified patients with advanced HF. However, current evidence shows that congestion in HF varies in quantity and distribution. This updated view advocates for a congestive-driven classification of HF according to onset (acute vs. chronic), regional distribution (systemic vs. pulmonary), compartment of distribution (intravascular vs. extravascular), and clinical vs. subclinical. Thus, this review will focus on the utility of circulating biomarkers for assessing and managing the different fluid overload phenotypes. This discussion focused on the clinical utility of the natriuretic peptides, carbohydrate antigen 125 (also called mucin 16), bio-adrenomedullin and mid-regional pro-adrenomedullin, ST2 (also known as interleukin-1 receptor-like 1), cluster of differentiation 146, troponin, C-terminal pro-endothelin-1, and parameters of haemoconcentration. The utility of circulation biomarkers on top of clinical evaluation, haemodynamics, and imaging needs to be better determined by dedicated studies. Some multiparametric frameworks in which these tools contribute to management are proposed.

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.

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.