Volenrelaxin (LY3540378) increases Renal Plasma Flow: A Randomized Phase 1 Trial

BACKGROUND AND HYPOTHESIS

Volenrelaxin, is a half-life-extended recombinant human relaxin protein developed for improving kidney perfusion and cardiorenal function. This study assessed the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of volenrelaxin following single- and multiple-ascending doses (SAD and MAD) administration.

METHODS

In this Phase 1, 4-part, randomized, double-blinded, placebo-controlled SAD and MAD study in healthy participants, SAD participants (n = 56) received an intravenous (IV) or subcutaneous (SC) dose of volenrelaxin or placebo in a dose-ascending manner. MAD participants (n = 77) received volenrelaxin or placebo SC once weekly for 5 weeks. Effective renal plasma flow (ERPF) and measured glomerular filtration rate (mGFR) were determined by para-aminohippurate and iohexol clearance, respectively.

RESULTS

Volenrelaxin demonstrated an extended half-life and increased acute and chronic placebo-adjusted ERPF change from baseline by 50% and 44%, respectively (p < 0.0001). Measured GFR was unchanged, while filtration fraction and afferent/efferent renal arteriolar resistances were reduced. Systolic and diastolic blood pressures decreased, and pulse rate increased with increasing volenrelaxin exposures, demonstrating maximal model-derived placebo-adjusted changes (90% confidence interval) of -6.16 (-8.04, -4.28) mmHg, -6.10 (-7.61, -4.58) mmHg, and + 4.39 (3.38, 5.39) bpm, respectively. Adverse events were mild, with no difference in orthostatic hypotension between volenrelaxin and placebo.

CONCLUSION

Volenrelaxin was well-tolerated, safe and suitable for weekly SC dosing. Volenrelaxin showed a sustained improvement in kidney perfusion upon repeated dosing, supporting further clinical development in chronic kidney disease and chronic heart failure. Clinical trial registration: NCT04768855.

Contemporary Decongestion Strategies in Patients Hospitalized for Heart Failure: A National Community-Based Cohort Study

BACKGROUND

Heart failure (HF) is a leading cause of hospitalization in the United States. Decongestion remains a central goal of inpatient management, but contemporary decongestion practices and associated weight loss have not been well characterized nationally.

OBJECTIVES

This study aimed to describe contemporary inpatient diuretic practices and clinical predictors of weight loss in patients hospitalized for HF.

METHODS

The authors identified HF hospitalizations from 2015 to 2022 in a U.S. national database aggregating deidentified patient-level electronic health record data across 31 geographically diverse community-based health systems. The authors report patient characteristics and inpatient weight change as a primary indicator of decongestion. Predictors of weight loss were evaluated using multivariable models. Temporal trends in inpatient diuretic practices, including augmented diuresis strategies such as adjunctive thiazides and continuous diuretic infusions, were assessed.

RESULTS

The study cohort included 262,673 HF admissions across 165,482 unique patients. The median inpatient weight loss was 5.3 pounds (Q1-Q3: 0.0-12.8 pounds) or 2.4 kg (Q1-Q3: 0.0-5.8 kg). Discharge weight was higher than admission weight in 20% of encounters. An increase of ≥0.3 mg/dL in serum creatinine from admission to inpatient peak occurred in >30% of hospitalizations and was associated with less weight loss. Adjunctive diuretic agents were utilized in <20% of encounters but were associated with greater weight loss.

CONCLUSIONS

In a large-scale U.S. community-based cohort study of HF hospitalizations, estimated weight loss from inpatient decongestion remains highly variable, with weight gain observed across many admissions. Augmented diuresis strategies were infrequently used. Comparative effectiveness trials are needed to establish optimal strategies for inpatient decongestion for acute HF.

Kidney and heart failure events are bidirectionally associated in patients with type 2 diabetes and cardiovascular disease

AIMS

This study aimed to evaluate the bidirectional relationship between kidney and cardiovascular (CV) events in trial participants with type 2 diabetes and CV disease.

METHODS AND RESULTS

Post hoc analyses of EMPA-REG OUTCOME using Cox regression models were performed to assess the association of baseline factors with risk of a kidney event and bidirectional associations of incident kidney events and CV events. Among placebo-treated participants, baseline factors significantly associated with greater kidney event risk included lower baseline estimated glomerular filtration rate, albuminuria, higher uric acid, low-density lipoprotein cholesterol levels, and prior heart failure (HF). Coronary artery disease was not associated with increased risk. In placebo-treated participants, occurrence of an incident non-fatal kidney event increased the subsequent risk of hospitalization for HF (HHF) but not 3-point major adverse CV events (non-fatal stroke, non-fatal myocardial infarction, and CV death). Vice versa, HHF (but not myocardial infarction/stroke) increased the risk of subsequent kidney events. These associations were generally also seen in empagliflozin-treated participants and in the overall population. Interestingly, the risk of kidney events following HHF was not significantly increased in the relatively small number of placebo-treated participants already diagnosed with HF at baseline.

CONCLUSIONS

These findings demonstrate a bidirectional inter-relationship between HHF and kidney events. Further exploration of this relationship and strategies to optimize the use of therapies to reduce both kidney and HF outcomes is warranted.

COVID-19-Associated Acute Kidney Injury and Longitudinal Kidney Outcomes

Importance

COVID-19 infection is associated with a high incidence of acute kidney injury (AKI). Although rapid kidney function decline has been reported in the first few months after COVID-19-associated AKI (COVID-AKI), the longer-term association of COVID-AKI with kidney function remains unknown.

Objective

To assess long-term kidney outcomes of patients who had COVID-19-associated AKI.

Design, Setting, and Participants

This was a retrospective longitudinal multicenter cohort study conducted in a large hospital system using electronic health records data on adult hospitalized patients with AKI and COVID-19 or other illnesses. Included patients were hospitalized during the COVID-19 pandemic (March 2020-June 2022), were screened for SARS-CoV-2, had AKI, and survived to discharge, or had been hospitalized during the 5 years before the pandemic (October 2016-January 2020), had a positive influenza A or B test result, had AKI, and survived to discharge. Patients were followed up for a maximum of 2 years after hospital discharge. Data analyses were performed from December 2022 to November 2023.

Exposure

COVID-19 and influenza.

Main Outcomes and Measures

The primary outcome was major adverse kidney events (MAKE), defined as a composite of mortality and worsened kidney function (estimated glomerular filtration rate [eGFR] decline by ≥25% from discharge eGFR or kidney failure requiring dialysis). Multivariable time-to-event analyses were performed to compare MAKE between individuals with COVID-AKI and those who had AKI associated with other illnesses hospitalized during the same period. For further comparison, this outcome was assessed for a historic cohort of patients with influenza-associated AKI.

Results

The study cohort included 9624 hospitalized patients (mean [SD] age, 69.0 [15.7] years; 4955 [51.5%] females) with AKI, including 987 patients with COVID-AKI, 276 with influenza-associated AKI, and 8361 with AKI associated with other illnesses (other-AKI). Compared with the other 2 groups, patients with COVID-19-associated AKI were slightly younger in age, had a higher baseline eGFR, worse baseline comorbidity scores, higher markers of illness severity, and longer hospital stay. Compared with the other-AKI group, the COVID-AKI group had lower MAKE (adjusted hazard ratio [aHR], 0.67; 95% CI, 0.59-0.75) due to lower all-cause mortality (aHR, 0.31; 95% CI, 0.24-0.39) and lower rates of worsened kidney function (aHR, 0.78; 95% CI, 0.69-0.88).

Conclusions and Relevance

The findings of this multicenter cohort study indicate that survivors of hospitalization with COVID-AKI experience lower rates of MAKE, long-term kidney function decline, and mortality compared with patients with AKI associated with other illnesses.

Serial direct sodium removal in patients with heart failure and diuretic resistance

AIMS

Loop diuretics may exacerbate cardiorenal syndrome (CRS) in heart failure (HF). Direct sodium removal (DSR) using the peritoneal membrane, in conjunction with complete diuretic withdrawal, may improve CRS and diuretic resistance.

METHODS AND RESULTS

Patients with HF requiring high-dose loop diuretics were enrolled in two prospective, single-arm studies: RED DESERT (n = 8 euvolaemic patients), and SAHARA (n = 10 hypervolaemic patients). Loop diuretics were withdrawn, and serial DSR was utilized to achieve and maintain euvolaemia. At baseline, participants required a median 240 mg (interquartile range [IQR] 200-400) oral furosemide equivalents/day, which was withdrawn in all participants during DSR (median time of DSR 4 weeks [IQR 4-6]). Diuretic response (queried by formal 40 mg intravenous furosemide challenge and 6 h urine sodium quantification) increased substantially from baseline (81 ± 37 mmol) to end of DSR (223 ± 71 mmol, p < 0.001). Median time to re-initiate diuretics was 87 days, and the median re-initiation dose was 8% (IQR 6-10%) of baseline. At 1 year, diuretic dose remained substantially below baseline (30 [IQR 7.5-40] mg furosemide equivalents/day). Multiple dimensions of kidney function such as filtration, uraemic toxin excretion, kidney injury, and electrolyte handling improved (p < 0.05 for all). HF-related biomarkers including N-terminal pro-B-type natriuretic peptide, carbohydrate antigen-125, soluble ST2, interleukin-6, and growth differentiation factor-15 (p < 0.003 for all) also improved.

CONCLUSIONS

In patients with HF and diuretic resistance, serial DSR therapy with loop diuretic withdrawal was feasible and associated with substantial and persistent improvement in diuretic resistance and several cardiorenal parameters. If replicated in randomized controlled studies, DSR may represent a novel therapy for diuretic resistance and CRS.

CLINICAL TRIAL REGISTRATION

RED DESERT (NCT04116034), SAHARA (NCT04882358).

Integration of implantable device therapy in patients with heart failure. A clinical consensus statement from the Heart Failure Association (HFA) and European Heart Rhythm Association (EHRA) of the European Society of Cardiology (ESC)

Implantable devices form an integral part of the management of patients with heart failure (HF) and provide adjunctive therapies in addition to cornerstone drug treatment. Although the number of these devices is growing, only few are supported by robust evidence. Current devices aim to improve haemodynamics, improve reverse remodelling, or provide electrical therapy. A number of these devices have guideline recommendations and some have been shown to improve outcomes such as cardiac resynchronization therapy, implantable cardioverter-defibrillators and long-term mechanical support. For others, more evidence is still needed before large-scale implementation can be strongly advised. Of note, devices and drugs can work synergistically in HF as improved disease control with devices can allow for further optimization of drug therapy. Therefore, some devices might already be considered early in the disease trajectory of HF patients, while others might only be reserved for advanced HF. As such, device therapy should be integrated into HF care programmes. Unfortunately, implementation of devices, including those with the greatest evidence, in clinical care pathways is still suboptimal. This clinical consensus document of the Heart Failure Association (HFA) and European Heart Rhythm Association (EHRA) of the European Society of Cardiology (ESC) describes the physiological rationale behind device-provided therapy and also device-guided management, offers an overview of current implantable device options recommended by the guidelines and proposes a new integrated model of device therapy as a part of HF care.

Empagliflozin in Heart Failure: Regional Nephron Sodium Handling Effects

SIGNIFICANCE STATEMENT

The effect of sodium-glucose cotransporter-2 inhibitors (SGLT2i) on regional tubular sodium handling is poorly understood in humans. In this study, empagliflozin substantially decreased lithium reabsorption in the proximal tubule (PT) (a marker of proximal tubular sodium reabsorption), a magnitude out of proportion to that expected with only inhibition of sodium-glucose cotransporter-2. This finding was not driven by an "osmotic diuretic" effect; however, several parameters changed in a manner consistent with inhibition of the sodium-hydrogen exchanger 3. The large changes in proximal tubular handling were acutely buffered by increased reabsorption in both the loop of Henle and the distal nephron, resulting in the observed modest acute natriuresis with these agents. After 14 days of empagliflozin, natriuresis waned due to increased reabsorption in the PT and/or loop of Henle. These findings confirm in humans that SGLT2i have complex and important effects on renal tubular solute handling.

BACKGROUND

The effect of SGLT2i on regional tubular sodium handling is poorly understood in humans but may be important for the cardiorenal benefits.

METHODS

This study used a previously reported randomized, placebo-controlled crossover study of empagliflozin 10 mg daily in patients with diabetes and heart failure. Sodium handling in the PT, loop of Henle (loop), and distal nephron was assessed at baseline and day 14 using fractional excretion of lithium (FELi), capturing PT/loop sodium reabsorption. Assessments were made with and without antagonism of sodium reabsorption through the loop using bumetanide.

RESULTS

Empagliflozin resulted in a large decrease in sodium reabsorption in the PT (increase in FELi=7.5%±10.6%, P = 0.001), with several observations suggesting inhibition of PT sodium hydrogen exchanger 3. In the absence of renal compensation, this would be expected to result in approximately 40 g of sodium excretion/24 hours with normal kidney function. However, rapid tubular compensation occurred with increased sodium reabsorption both in the loop ( P < 0.001) and distal nephron ( P < 0.001). Inhibition of sodium-glucose cotransporter-2 did not attenuate over 14 days of empagliflozin ( P = 0.14). However, there were significant reductions in FELi ( P = 0.009), fractional excretion of sodium ( P = 0.004), and absolute fractional distal sodium reabsorption ( P = 0.036), indicating that chronic adaptation to SGLT2i results primarily from increased reabsorption in the loop and/or PT.

CONCLUSIONS

Empagliflozin caused substantial redistribution of intrarenal sodium delivery and reabsorption, providing mechanistic substrate to explain some of the benefits of this class. Importantly, the large increase in sodium exit from the PT was balanced by distal compensation, consistent with SGLT2i excellent safety profile.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

ClinicalTrials.gov ( NCT03027960 ).

Association of Urine Galectin-3 With Cardiorenal Outcomes in Patients With Heart Failure

BACKGROUND AND OBJECTIVES

Approaches to distinguishing pathological cardiorenal dysfunction in heart failure (HF) from functional/hemodynamically mediated changes in serum creatinine are needed. We investigated urine galectin-3 as a candidate biomarker of renal fibrosis and a prognostic indicator of cardiorenal dysfunction phenotypes.

METHODS

We measured urine galectin-3 in 2 contemporary HF cohorts: the Yale Transitional Care Clinic (YTCC) cohort (n = 132) and the Treatment of Preserved Cardiac Function Heart Failure with an Aldosterone Antagonist (TOPCAT) trial (n = 434). We assessed the association of urine galectin-3 with all-cause mortality in both cohorts and the association with an established marker of renal tissue fibrosis, urinary amino-terminal propeptide of type III procollagen (PIIINP) in TOPCAT.

RESULTS

In the YTCC cohort, there was significant effect modification between higher urine galectin-3 and lower estimated glomerular filtration rates (eGFRs) (Pinteraction = 0.046), such that low eGFR levels had minimal prognostic importance if urine galectin-3 levels were low, but they were important and indicated high risk if urine galectin-3 levels were high. Similar observations were noted in the TOPCAT study (Pinteraction = 0.002). In TOPCAT, urine galectin-3 also positively correlated with urine PIIINP at both baseline (r = 0.43; P < 0.001) and at 12 months (r = 0.42; P < 0.001).

CONCLUSIONS

Urine galectin-3 levels correlated with an established biomarker of renal fibrosis in 2 cohorts and was able to differentiate high- vs low-risk phenotypes of chronic kidney disease in HF. These proof-of-concept results indicate that additional biomarker research to differentiate cardiorenal phenotypes is warranted.

Randomized controlled trial of urinE chemiStry guided aCute heArt faiLure treATmEnt (ESCALATE): Rationale and design

Diuresis to achieve decongestion is a central aim of therapy in patients hospitalized for acute decompensated heart failure (ADHF). While multiple clinical trials have investigated initial diuretic strategies for a designated period of time, there is a paucity of evidence to guide diuretic titration strategies continued until decongestion is achieved. The use of urine chemistries (urine sodium and creatinine) in a natriuretic response prediction equation accurately estimates natriuresis in response to diuretic dosing, but a randomized clinical trial is needed to compare a urine chemistry-guided diuresis strategy with a strategy of usual care. The urinE chemiStry guided aCute heArt faiLure treATmEnt (ESCALATE) trial is designed to test the hypothesis that protocolized diuretic therapy guided by spot urine chemistry through completion of intravenous diuresis will be superior to usual care and improve outcomes over the 14 days following randomization. ESCALATE will randomize and obtain complete data on 450 patients with acute heart failure to a diuretic strategy guided by urine chemistry or a usual care strategy. Key inclusion criteria include an objective measure of hypervolemia with at least 10 pounds of estimated excess volume, and key exclusion criteria include significant valvular stenosis, hypotension, and a chronic need for dialysis. Our primary outcome is days of benefit over the 14 days after randomization. Days of benefit combines patient symptoms captured by global clinical status with clinical state quantifying the need for hospitalization and intravenous diuresis. CLINICAL TRIAL REGISTRATION: NCT04481919.

Outcomes Associated with Sodium-Glucose Cotransporter-2 Inhibitor Use in Acute Heart Failure Hospitalizations Complicated by AKI

Key Points

In a multicenter retrospective cohort study of adults hospitalized with acute heart failure, exposure to sodium-glucose cotransporter-2 inhibitor during AKI was associated with lower risk of 30-day mortality. Exposure to sodium-glucose cotransporter-2 inhibitor during acute heart failure–associated AKI was associated with no difference in time to renal recovery. The findings were reproducible in inverse probability-weighted analysis.

Background

Although sodium-glucose cotransporter-2 inhibitor (SGLT2i) use during acute heart failure (AHF) hospitalizations is associated with symptomatic improvement, reduction in rehospitalizations, and mortality, these medications are often withheld during AKI because of concerns about worsening GFR. We aimed to investigate the safety of SGLT2i exposure during AKI among patients hospitalized with AHF. We hypothesized that SGLT2i exposure would not worsen mortality but may prolong return of creatinine to baseline.

Methods

This was a retrospective study of adults hospitalized across five Yale New Haven Health System hospitals between January 2020 and May 2022 with AHF complicated by Kidney Disease Improving Global Outcomes–defined AKI. Patients with stage 5 CKD and those with potential contraindications to SGLT2i were excluded. We tested the association of SGLT2i use with kidney function recovery at 14 days and death at 30 days using time-varying, multivariable Cox-regression analyses.

Results

Of 3305 individuals hospitalized with AHF and AKI, 356 received SGLT2i after AKI diagnosis either as initiation or continuation. The rate of renal recovery was not significantly different among those exposed and unexposed to SGLT2i after AKI (adjusted hazard ratio, 0.94; 95% confidence interval, 0.79 to 1.11; P = 0.46). SGLT2i exposure was associated with lower risk of 30-day mortality (adjusted hazard ratio, 0.45; 95% confidence interval, 0.23 to 0.87; P = 0.02). Sensitivity analyses using an inverse probability-weighted time-varying Cox regression analysis and using alternate definitions of AHF with different NT-proBNP cutoffs yielded similar results. Rates of renal recovery were similar between the exposed and unexposed cohorts regardless of the proximity of SGLT2i exposure to AKI diagnosis.

Conclusion

In adults experiencing AHF-associated AKI, exposure to SGLT2i was associated with decreased mortality and no delay in renal recovery. Prospective studies are needed to elucidate the effect of SGLT2i exposure during AKI, particularly during heart failure hospitalizations.

Effect of Sotagliflozin on Early Mortality and Heart Failure-Related Events: A Post Hoc Analysis of SOLOIST-WHF

BACKGROUND

Approximately 25% of patients admitted to hospitals for worsening heart failure (WHF) are readmitted within 30 days.

OBJECTIVES

The authors conducted a post hoc analysis of the SOLOIST-WHF (Effect of Sotagliflozin on Cardiovascular Events in Patients With Type 2 Diabetes Post-WHF) trial to evaluate the efficacy of sotagliflozin versus placebo to decrease mortality and HF-related events among patients who began study treatment on or before discharge from their index hospitalization.

METHODS

The main endpoint of interest was cardiovascular death or HF-related event (HF hospitalization or urgent care visit) occurring within 90 and 30 days after discharge for the index WHF hospitalization. Treatment comparisons were by proportional hazards models, generating HRs, 95% CIs, and P values.

RESULTS

Of 1,222 randomized patients, 596 received study drug on or before their date of discharge. Sotagliflozin reduced the main endpoint at 90 days after discharge (HR: 0.54 [95% CI: 0.35-0.82]; P = 0.004) and at 30 days (HR: 0.49 [95% CI: 0.27-0.91]; P = 0.023) and all-cause mortality at 90 days (HR: 0.39 [95% CI: 0.17-0.88]; P = 0.024). In subgroup analyses, sotagliflozin reduced the 90-day main endpoint regardless of sex, age, estimated glomerular filtration rate, N-terminal pro-B-type natriuretic peptide, left ventricular ejection fraction, or mineralocorticoid receptor agonist use. Sotagliflozin was well-tolerated but with slightly higher rates of diarrhea and volume-related events than placebo.

CONCLUSIONS

Starting sotagliflozin before discharge in patients with type 2 diabetes hospitalized for WHF significantly decreased cardiovascular deaths and HF events through 30 and 90 days after discharge, emphasizing the importance of beginning sodium glucose cotransporter treatment before discharge.

Critical Analysis of the Effects of SGLT2 Inhibitors on Renal Tubular Sodium, Water and Chloride Homeostasis and Their Role in Influencing Heart Failure Outcomes

SGLT2 (sodium-glucose cotransporter 2) inhibitors interfere with the reabsorption of glucose and sodium in the early proximal renal tubule, but the magnitude and duration of any ensuing natriuretic or diuretic effect are the result of an interplay between the degree of upregulation of SGLT2 and sodium-hydrogen exchanger 3, the extent to which downstream compensatory tubular mechanisms are activated, and (potentially) the volume set point in individual patients. A comprehensive review and synthesis of available studies reveals several renal response patterns with substantial variation across studies and clinical settings. However, the common observation is an absence of a large acute or chronic diuresis or natriuresis with these agents, either when given alone or combined with other diuretics. This limited response results from the fact that renal compensation to these drugs is rapid and nearly complete within a few days or weeks, preventing progressive volume losses. Nevertheless, the finding that fractional excretion of glucose and lithium (the latter being a marker of proximal sodium reabsorption) persists during long-term treatment with SGLT2 inhibitors indicates that pharmacological tolerance to the effects of these drugs at the level of the proximal tubule does not meaningfully occur. This persistent proximal tubular effect of SGLT2 inhibitors can be hypothesized to produce a durable improvement in the internal set point for volume homeostasis, which may become clinically important during times of fluid expansion. However, it is difficult to know whether a treatment-related change in the volume set point actually occurs or contributes to the effect of these drugs to reduce the risk of major heart failure events. SGLT2 inhibitors exert cardioprotective effects by a direct effect on cardiomyocytes that is independent of the presence of or binding to SGLT2 or the actions of these drugs on the proximal renal tubule. Nevertheless, changes in the volume set point mediated by SGLT2 inhibitors might potentially act cooperatively with the direct favorable molecular and cellular effects of these drugs on cardiomyocytes to mediate their benefits on the development and clinical course of heart failure.

Updates in Cardiorenal Syndrome

Cardiorenal syndrome is a term that refers to a collection of disorders involving both the heart and kidneys, encompassing multi-directional pathways between the 2 organs mediated through low arterial perfusion, venous congestion, and neurohormonal activation. The pathophysiology is complex and includes hemodynamic and neurohormonal changes, but inconsistent findings from recent studies suggest this is very heterogenous disorder. Management for ADHF remains focused on decongestion and neurohormonal blockade to overcome the intense sodium and fluid avidity of the CRS.

A randomized clinical trial assessing the effect of automated medication-targeted alerts on acute kidney injury outcomes

Acute kidney injury is common among hospitalized individuals, particularly those exposed to certain medications, and is associated with substantial morbidity and mortality. In a pragmatic, open-label, National Institutes of Health-funded, parallel group randomized controlled trial (clinicaltrials.gov NCT02771977), we investigate whether an automated clinical decision support system affects discontinuation rates of potentially nephrotoxic medications and improves outcomes in patients with AKI. Participants included 5060 hospitalized adults with AKI and an active order for any of three classes of medications of interest: non-steroidal anti-inflammatory drugs, renin-angiotensin-aldosterone system inhibitors, or proton pump inhibitors. Within 24 hours of randomization, a medication of interest was discontinued in 61.1% of the alert group versus 55.9% of the usual care group (relative risk 1.08, 1.04 - 1.14, p = 0.0003). The primary outcome - a composite of progression of acute kidney injury, dialysis, or death within 14 days - occurred in 585 (23.1%) of individuals in the alert group and 639 (25.3%) of patients in the usual care group (RR 0.92, 0.83 - 1.01, p = 0.09). Trial Registration Clinicaltrials.gov NCT02771977.

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.

In-Hospital Observation on Oral Diuretics After Treatment for Acute Decompensated Heart Failure: Evaluating the Utility

BACKGROUND

Following treatment for acute decompensated heart failure, in-hospital observation on oral diuretics (OOD) is recommended, assuming it provides actionable information on discharge diuretic dosing and thus reduces readmissions.

METHODS

In the Mechanisms of Diuretic Resistance (MDR) cohort, we analyzed in-hospital measures of diuretic response, provider's decisions, and diuretic response ≈30 days postdischarge. In a Yale multicenter cohort, we assessed if in-hospital OOD was associated with 30-day readmission risk. The main objective of this study was to evaluate the utility of in-hospital OOD.

RESULTS

Of the 468 patients in the MDR cohort, 57% (N=265) underwent in-hospital OOD. During the OOD, weight change and net fluid balance correlated poorly with each other (r=0.36). Discharge diuretic dosing was similar between patients who had increased, stable, or decreased weight (decreased discharge dose from OOD dose in 77% versus 72% versus 70%, respectively), net fluid status (decreased discharge dose from OOD dose in 100% versus 69% versus 74%, respectively), and urine output (decreased discharge dose from OOD dose in 69% versus 79% versus 72%, respectively) during the 24-hour OOD period (P>0.27 for all). In participants returning at 30 days for formal quantification of outpatient diuretic response (n=98), outpatient and inpatient OOD natriuresis was poorly correlated (r=0.26). In the Yale multicenter cohort (n=18 454 hospitalizations), OOD occurred in 55% and was not associated with 30-day hospital readmission (hazard ratio, 0.98 [95% CI, 0.93-1.05]; P=0.51).

CONCLUSIONS

In-hospital OOD did not provide actionable information on diuretic response, was not associated with outpatient dose selection, did not predict subsequent outpatient diuretic response, and was not associated with lower readmission rate. Additional research is needed to replicate these findings and understand if these resources could be better allocated elsewhere.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02546583.

Improvement in Renal Function During the Treatment of Acute Decompensated Heart Failure: Relationship With Markers of Renal Tubular Injury and Prognostic Importance

BACKGROUND

Improvement in renal function (IRF) in acute decompensated heart failure is associated with adverse outcomes. The mechanisms driving this paradox remain undefined.

METHODS

Using the ROSE-AHF study (Renal Optimization Strategies Evaluation-Acute Heart Failure), 277 patients were grouped according to renal function, with IRF defined by a ≥20% increase (N=75), worsening renal function by a ≥20% decline (N=53), and stable renal function (SRF) by a <20% change (N=149) in estimated glomerular filtration rate between baseline and 72 hours. Three well-validated renal tubular injury markers, NGAL (neutrophil gelatinase-associated lipocalin), NAG (N-acetyl-β-d-glucosaminidase), and KIM-1 (kidney injury molecule 1), were evaluated at baseline and 72 hours. Patients were also classified by the pattern of change in these markers.

RESULTS

Patients with IRF had the lowest admission estimated glomerular filtration rate (IRF, 37 [28 to 51] mL/min per 1.73 m2; worsening renal function, 43 [35 to 55] mL/min per 1.73 m2; and SRF, 43 [32 to 55] mL/min per 1.73 m2; Ptrend=0.032) but greater cumulative urine output (IRF, 8780 [7025 to 11 208] mL; worsening renal function, 7860 [5555 to 9765] mL; and SRF, 8150 [6325 to 10 456] mL; Ptrend=0.024) and weight loss (IRF, -9.0 [-12.4 to -5.3] lb; worsening renal function, -5.1 [-8.1 to -1.3] lb; and SRF, -7.1 [-11.9 to -3.2] lb; Ptrend<0.001) despite similar diuretic doses (Ptrend=0.16). There were no differences in the relative change in NGAL, NAG, or KIM-1 between renal function groups (Ptrend>0.19 for all). Patients with IRF had worse survival than patients with SRF (27% versus 54%; hazard ratio, 1.98 [1.10-3.58]; P=0.024).

CONCLUSIONS

IRF during decongestive therapy for acute decompensated heart failure was not associated with improved markers of renal tubular injury and was associated with worsened survival, likely driven by the presence of greater underlying cardiorenal dysfunction and more severe congestion.

Effect of Torsemide vs Furosemide After Discharge on All-Cause Mortality in Patients Hospitalized With Heart Failure: The TRANSFORM-HF Randomized Clinical Trial

IMPORTANCE

Although furosemide is the most commonly used loop diuretic in patients with heart failure, some studies suggest a potential benefit for torsemide.

OBJECTIVE

To determine whether torsemide results in decreased mortality compared with furosemide among patients hospitalized for heart failure.

DESIGN, SETTING, AND PARTICIPANTS

TRANSFORM-HF was an open-label, pragmatic randomized trial that recruited 2859 participants hospitalized with heart failure (regardless of ejection fraction) at 60 hospitals in the United States. Recruitment occurred from June 2018 through March 2022, with follow-up through 30 months for death and 12 months for hospitalizations. The final date for follow-up data collection was July 2022.

INTERVENTIONS

Loop diuretic strategy of torsemide (n = 1431) or furosemide (n = 1428) with investigator-selected dosage.

MAIN OUTCOMES AND MEASURES

The primary outcome was all-cause mortality in a time-to-event analysis. There were 5 secondary outcomes with all-cause mortality or all-cause hospitalization and total hospitalizations assessed over 12 months being highest in the hierarchy. The prespecified primary hypothesis was that torsemide would reduce all-cause mortality by 20% compared with furosemide.

RESULTS

TRANSFORM-HF randomized 2859 participants with a median age of 65 years (IQR, 56-75), 36.9% were women, and 33.9% were Black. Over a median follow-up of 17.4 months, a total of 113 patients (53 [3.7%] in the torsemide group and 60 [4.2%] in the furosemide group) withdrew consent from the trial prior to completion. Death occurred in 373 of 1431 patients (26.1%) in the torsemide group and 374 of 1428 patients (26.2%) in the furosemide group (hazard ratio, 1.02 [95% CI, 0.89-1.18]). Over 12 months following randomization, all-cause mortality or all-cause hospitalization occurred in 677 patients (47.3%) in the torsemide group and 704 patients (49.3%) in the furosemide group (hazard ratio, 0.92 [95% CI, 0.83-1.02]). There were 940 total hospitalizations among 536 participants in the torsemide group and 987 total hospitalizations among 577 participants in the furosemide group (rate ratio, 0.94 [95% CI, 0.84-1.07]). Results were similar across prespecified subgroups, including among patients with reduced, mildly reduced, or preserved ejection fraction.

CONCLUSIONS AND RELEVANCE

Among patients discharged after hospitalization for heart failure, torsemide compared with furosemide did not result in a significant difference in all-cause mortality over 12 months. However, interpretation of these findings is limited by loss to follow-up and participant crossover and nonadherence.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03296813.

Rates of In-Hospital Decongestion and Association with Mortality and Cardiovascular Outcomes Among Patients Admitted for Acute Heart Failure

BACKGROUND

Decongestion is an important goal in the management of acute heart failure. Whether the rate of decongestion is associated with mortality and cardiovascular outcomes is unknown.

METHODS

Using data from 4133 patients from the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study With Tolvaptan (EVEREST) trial, we used multivariable Cox regression models to evaluate the association between rates of in-hospital change in assessments of volume overload, including b-type natriuretic peptide (BNP), N-terminal pro b-type natriuretic peptide (NT-proBNP), as well as change in hemoconcentration, with risk of all-cause mortality and a composite outcome of cardiovascular mortality or heart failure hospitalization.

RESULTS

More rapid rates of in-hospital decongestion were associated with decreased risk of mortality and the composite outcome over a median 10-month follow-up. In reference to the quartile of slowest decline, the quartile with the fastest BNP and NT-proBNP decline had lower hazards of mortality (hazard rate [HR] = 0.43 [0.31, 0.59] and HR = 0.27 [0.19, 0.40], respectively) and composite outcome (HR = 0.49 [0.39, 0.60] and HR = 0.54 [0.42, 0.71], respectively). In reference to the quartile of slowest increase, the quartile with the fastest hematocrit increase had lower hazards of mortality (HR = 0.77 [0.62, 0.95]) and composite outcome (HR = 0.75 [0.64, 0.88]). Results were also consistent when models were repeated using propensity-score matching.

CONCLUSIONS

Faster rates of decongestion are associated with reduced risk of mortality and a composite of cardiovascular mortality and heart failure hospitalization. It remains unknown whether more rapid decongestion provides cardiovascular benefit or whether it serves as a proxy for less treatment resistant heart failure.

Rates of Reversal of Volume Overload in Hospitalized Acute Heart Failure: Association With Long-term Kidney Function

RATIONALE & OBJECTIVE

Achievement of decongestion in acute heart failure (AHF) is associated with improved survival and cardiovascular outcomes but can be associated with acute declines in estimated glomerular filtration rate (eGFR). We examined whether the rate of in-hospital decongestion is associated with longer term kidney function decline.

STUDY DESIGN

Post hoc analysis of trial data.

SETTINGS & PARTICIPANTS

Patients with ≥2 measures of kidney function (n = 3,500) from the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study With Tolvaptan (EVEREST) trial.

EXPOSURE

In-hospital rate of change in assessments of volume overload, including B-type natriuretic peptide (BNP), N-terminal pro-B-type natriuretic peptide (NT-proBNP), and clinical congestion score (0-12); and rate of change in hemoconcentration including measures of hematocrit, albumin, and total protein.

OUTCOME

Incident chronic kidney disease GFR category 4 or worse (chronic kidney disease [CKD] categories G4-G5; defined by a new eGFR of <30 mL/min/1.73 m²) and eGFR decline of >40%.

ANALYTICAL APPROACH

Multivariable cause-specific hazards models.

RESULTS

Over median 10-month follow-up period, faster decreases in volume overload and more rapid increases in hemoconcentration were associated with a decreased risk of incident CKD G4-G5 and eGFR decline of >40%. In adjusted analyses, for every 6% faster decline in BNP per week, there was a 32% lower risk of both incident CKD G4-G5 (HR, 0.68 [95% CI, 0.58-0.79]) and eGFR decline of >40% (HR, 0.68 [95% CI, 0.57-0.80]). For every 1% faster increase per week in absolute hematocrit, there was a lower risk for both incident CKD G4-G5 (HR, 0.73 [95% CI, 0.64-0.84]) and eGFR decline of >40% (HR, 0.82 [95% CI, 0.71-0.95]), with results consistent for other biomarkers.

LIMITATIONS

Possibility of residual confounding.

CONCLUSIONS

These results provide reassurance that more rapid decongestion in patients with AHF does not increase the risk of adverse kidney outcomes in patients with heart failure.

Hemoconcentration of Creatinine Minimally Contributes to Changes in Creatinine during the Treatment of Decompensated Heart Failure

Background

Worsening serum creatinine is common during treatment of acute decompensated heart failure (ADHF). A possible contributor to creatinine increase is diuresis-induced changes in volume of distribution (VD) of creatinine as total body water (TBW) contracts around a fixed mass of creatinine. Our objective was to better understand the filtration and nonfiltration factors driving change in creatinine during ADHF.

Methods

Participants in the ROSE-AHF trial with baseline to 72-hour serum creatinine; net fluid output; and urinary KIM-1, NGAL, and NAG were included (n=270). Changes in VD were calculated by accounting for measured input and outputs from weight-based calculated TBW. Changes in observed creatinine (Cr_observed) were compared with predicted changes in creatinine after accounting for alterations in VD and non-steady state conditions using a kinetic GFR equation (Cr_{72HR Kinetic}).

Results

When considering only change in VD, the median diuresis to elicit a ≥0.3 mg/dl rise in creatinine was -7526 ml (IQR, -5932 to -9149). After accounting for stable creatinine filtration during diuresis, a change in VD alone was insufficient to elicit a ≥0.3 mg/dl rise in creatinine. Larger estimated decreases in VD were paradoxically associated with improvement in Cr_observed (r=-0.18, P=0.003). Overall, -3% of the change in eCr_{72HR Kinetic} was attributable to the change in VD. A ≥0.3 mg/dl rise in eCr_{72HR Kinetic} was not associated with worsening of KIM-1, NGAL, NAG, or postdischarge survival (P>0.05 for all).

Conclusions

During ADHF therapy, increases in serum creatinine are driven predominantly by changes in filtration, with minimal contribution from change in VD.

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.

Mortality after acute kidney injury and acute interstitial nephritis in patients prescribed immune checkpoint inhibitor therapy

BACKGROUND

In patients receiving immune checkpoint inhibitor (ICI) therapy, acute kidney injury (AKI) is common, and can occur either from kidney injury unrelated to ICI use or from immune activation resulting in acute interstitial nephritis (AIN). In this study, we test the hypothesis that occurrence of AIN indicates a favorable treatment response to ICI therapy and therefore among patients who develop AKI while on ICI therapy, those with AIN will demonstrate greater survival compared with others with AKI.

METHODS

In this observational cohort study, we included participants initiated on ICI therapy between 2013 and 2019. We tested the independent association of AKI and estimated AIN (eAIN) with mortality up to 1 year after therapy initiation as compared with those without AKI using time-varying Cox proportional hazard models controlling for demographics, comorbidities, cancer type, stage, and therapy, and baseline laboratory values. We defined eAIN as those with a predicted probability of AIN >90th percentile derived from a recently validated diagnostic model.

RESULTS

Of 2207 patients initiated on ICIs, 617 (28%) died at 1 year and 549 (25%) developed AKI. AKI was independently associated with higher mortality (adjusted HR, 2.28 (95% CI 1.90 to 2.72)). Those AKI patients with eAIN had more severe AKI as reflected by a higher peak serum creatinine (3.3 (IQR 2.1-6.1) vs 1.4 (1.2-1.9) mg/dL, p<0.001) but exhibited lower mortality than those without eAIN in univariable analysis (HR 0.43 (95% CI 0.21 to 0.89)) and after adjusting for demographics, comorbidities, and cancer type and severity (adjusted HR 0.44 (95% CI 0.21 to 0.93)).

CONCLUSION

In patients treated with ICI, mortality was higher in those with AKI unrelated to ICI but lower in those where the underlying etiology was AIN. Future studies could evaluate the association of biopsy-proven or biomarker-proven AIN with mortality in those receiving ICI therapy.

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.

Evidence-Based Medical Therapy in Patients With Heart Failure With Reduced Ejection Fraction and Chronic Kidney Disease

Chronic kidney disease (CKD) as identified by a reduced estimated glomerular filtration rate (eGFR) is a common comorbidity in patients with heart failure with reduced ejection fraction (HFrEF). The presence of CKD is associated with more severe heart failure, and CKD itself is a strong independent risk factor of poor cardiovascular outcome. Furthermore, the presence of CKD often influences the decision to start, uptitrate, or discontinue possible life-saving HFrEF therapies. Because pivotal HFrEF randomized clinical trials have historically excluded patients with stage 4 and 5 CKD (eGFR <30 mL/min/1.73 m²), information on the efficacy and tolerability of HFrEF therapies in these patients is limited. However, more recent HFrEF trials with novel classes of drugs included patients with more severe CKD. In this review on medical therapy in patients with HFrEF and CKD, we show that for both all-cause mortality and the combined end point of cardiovascular death or heart failure hospitalization, most drug classes are safe and effective up to CKD stage 3B (eGFR minimum 30 mL/min/1.73 m²). For more severe CKD (stage 4), there is evidence of safety and efficacy of sodium glucose cotransporter 2 inhibitors, and to a lesser extent, angiotensin-converting enzyme inhibitors, vericiguat, digoxin and omecamtiv mecarbil, although this evidence is restricted to improvement of cardiovascular death/heart failure hospitalization. Data are lacking on the safety and efficacy for any HFrEF therapies in CKD stage 5 (eGFR < 15 mL/min/1.73 m² or dialysis) for either end point. Last, although an initial decline in eGFR is observed on initiation of several HFrEF drug classes (angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers/mineralocorticoid receptor antagonists/angiotensin receptor blocker neprilysin inhibitors/sodium glucose cotransporter 2 inhibitors), renal function often stabilizes over time, and the drugs maintain their clinical efficacy. A decline in eGFR in the context of a stable or improving clinical condition should therefore not be cause for concern and should not lead to discontinuation of life-saving HFrEF therapies.

Changes in inferior vena cava area represent a more sensitive metric than change in filling pressures during experimental manipulation of intravascular volume and tone

Aims

Remote monitoring of pulmonary artery pressure has reduced heart failure (HF) hospitalizations in chronic HF as elevation of pulmonary artery pressure provides information that can guide treatment. The venous system is characterized by high capacitance, thus substantial increases in intravascular volume can occur before filling pressures increase. The inferior vena cava (IVC) is a highly compliant venous conduit and thus a candidate for early detection of change in intravascular volume. We aimed to compare IVC cross‐sectional area using a novel sensor with cardiac filling pressures during experimental manipulation of volume status, vascular tone, and cardiac function.

Methods and results

Experiments were conducted in sheep to manipulate volume status (colloid infusion), vascular tone (nitroglycerin infusion) and cardiac function (rapid cardiac pacing). A wireless implantable IVC sensor was validated ex‐vivo and in‐vivo, and then used to measure the cross‐sectional area of the IVC. Right‐ and left‐sided cardiac filling pressures were obtained via right heart catheterization. The IVC sensor provided highly accurate and precise measurements of cross‐sectional area in ex‐vivo and in‐vivo validation. IVC area changes were more sensitive than the corresponding changes in cardiac filling pressures during colloid infusion (p < 0.001), vasodilatation (p < 0.001) and cardiac dysfunction induced by rapid pacing (p ≤ 0.02).

Conclusions

Inferior vena cava area can be remotely and accurately measured in real time with a wireless implantable sensor. Changes in IVC area are more sensitive than corresponding changes in filling pressures following experimental volume loading and fluid redistribution. Additional research is warranted to understand if remote monitoring of the IVC may have advantages over pressure‐based monitors in HF.

FGF-23 (Fibroblast Growth Factor-23) and Cardiorenal Interactions

BACKGROUND

Animal models implicate FGF-23 (fibroblast growth factor-23) as a direct contributor to adverse cardiorenal interactions such as sodium avidity, diuretic resistance, and neurohormonal activation, but this has not been conclusively demonstrated in humans. Therefore, we aimed to evaluate whether FGF-23 is associated with parameters of cardiorenal dysfunction in humans with heart failure, independent of confounding factors.

METHODS

One hundred ninety-nine outpatients with heart failure undergoing diuretic treatment at the Yale Transitional Care Center were enrolled and underwent blood collection, and urine sampling before and after diuretics.

RESULTS

FGF-23 was associated with several metrics of disease severity such as higher home loop diuretic dose and NT-proBNP (N-terminal pro-B-type natriuretic peptide), and lower estimated glomerular filtration rate, serum chloride, and serum albumin. Multivariable analysis demonstrated no statistically significant association between FGF-23 and sodium avidity measured by fractional excretion of sodium, or proximal or distal tubular sodium reabsorption, either before diuretic administration or at peak diuresis (P≥0.11 for all). Likewise, FGF-23 was not independently associated with parameters of diuretic resistance (diuretic excretion, cumulative urine and sodium output, and loop diuretic efficiency [P≥0.33 for all]) or neurohormonal activation (plasma or urine renin [P≥0.36 for all]). Moreover, the upper boundary of the 95% CI of all the partial correlations were ≤0.30, supporting the lack of meaningful correlations. FGF-23 was not associated with mortality in multivariable analysis (P=0.44).

CONCLUSIONS

FGF-23 was not meaningfully associated with any cardiorenal parameter in patients with heart failure. While our methods cannot rule out a small effect, FGF-23 is unlikely to be a primary driver of cardiorenal interactions.

Renal negative pressure treatment as a novel therapy for heart failure-induced renal dysfunction

Congestion is the primary pathophysiological lesion in most heart failure (HF) hospitalizations. Renal congestion increases renal tubular pressure, reducing glomerular filtration rate (GFR) and diuresis. Because each nephron is a fluid-filled column, renal negative pressure therapy (rNPT) applied to the urinary collecting system should reduce tubular pressure, potentially improving kidney function. We evaluated the renal response to rNPT in congestive HF. Ten anesthetized ∼80-kg pigs underwent instrumentation with bilateral renal pelvic JuxtaFlow catheters. GFR was determined by iothalamate clearance (mGFR) and renal plasma flow (RPF) by para-aminohippurate clearance. Each animal served as its own control with randomization of left versus right kidney to -30 mmHg rNPT or no rNPT. mGFR and RPF were measured simultaneously from the rNPT and no rNPT kidney. Congestive HF was induced via cardiac tamponade maintaining central venous pressure at 20-22.5 mmHg throughout the experiment. Before HF induction, rNPT increased natriuresis, diuresis, and mGFR compared with the control kidney (P < 0.001 for all). Natriuresis, diuresis, and mGFR decreased following HF (P < 0.001 for all) but were higher in rNPT kidney versus control (P < 0.001 for all). RPF decreased during HF (P < 0.001) without significant differences between rNPT treatments. During HF, the rNPT kidney had similar diuresis and natriuresis (P > 0.5 for both) and higher fractional excretion of sodium (P = 0.001) compared with the non-rNPT kidney in the no HF period. In conclusion, rNPT resulted in significantly increased diuresis, natriuresis, and mGFR, with or without experimental HF. rNPT improved key renal parameters of the congested cardiorenal phenotype.

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.

Sodium restriction in patients with chronic heart failure and reduced ejection fraction: A randomized controlled trial

BACKGROUND

Sodium restriction is recommended for patients with heart failure (HF) despite the lack of solid clinical evidence from randomized controlled trials. Whether or not sodium restrictions provide beneficial cardiac effects is not known.

METHODS

The present study is a randomized, double-blind, controlled trial of stable HF patients with ejection fraction ≤ 40%. Patients were allocated to sodium restriction (2 g of sodium/day) vs. control (3 g of sodium/day). The primary outcome was change in N-terminal pro-B-type natriuretic peptide (NT-proBNP) at 20 weeks. Secondary outcomes included quality of life and adverse safety events (HF readmission, blood pressure or electrolyte abnormalities).

RESULTS

Seventy patients were enrolled. Median baseline sodium consumption was 3268 (2225-4537) mg/day. Adherence to the intervention based on 24-hour urinary sodium was 32%. NT-proBNP and quality of life did not significantly change between groups (p > 0.05 for both). Adverse safety events were not significantly different between the arms (p > 0.6 for all). In the per protocol analysis, patients who achieved a sodium intake < 2500 mg/day at the intervention conclusion showed improvements in NT-proBNP levels (between-group difference: -55%, 95% confidence interval -27 to -73%; p = 0.002) and quality of life (between-group difference: -11 ± 5 points; p = 0.04). Blood pressure decreased in patients with lower sodium intake (between-group difference: -9 ± 5 mmHg; p = 0.05) without significant differences in symptomatic hypotension or other safety events (p > 0.3 for all).

CONCLUSIONS

Adherence assessed by 24-hour natriuresis and by the nutritionist was poor. The group allocated to sodium restriction did not show improvement in NT-proBNP. However, patients who achieved a sodium intake < 2500 mg/day appeared to have improvements in NT-proBNP and quality of life without any adverse safety signals.

CLINICALTRIALS

gov Identifier: NCT03351283.

Early diuretic strategies and the association with In-hospital and Post-discharge outcomes in acute heart failure

BACKGROUND

Decongestion is a primary goal during hospitalizations for decompensated heart failure (HF). However, data surrounding the preferred route and strategy of diuretic administration are limited with varying results in prior studies.

METHODS

This is a retrospective analysis using patients from ASCEND-HF with a stable diuretic strategy in the first 24 hours following randomization. Patients were divided into three groups: intravenous (IV) continuous, IV bolus and oral strategy. Baseline characteristics, in-hospital outcomes, 30-day composite cardiovascular mortality or HF rehospitalization and 180-day all-cause mortality were compared across groups. Inverse propensity weighted modeling was used for adjustment.

RESULTS

Among 5,738 patients with a stable diuretic regimen in the first 24 hours (80% of overall ASCEND trial), 3,944 (68.7%) patients received IV intermittent bolus administration of diuretics, 799 (13.9%) patients received IV continuous therapy and 995 (17.3%) patients with oral administration. Patients in the IV continuous group had a higher baseline creatinine (IV continuous 1.4 [1.1-1.7]; intermittent bolus 1.2 [1.0-1.6]; oral 1.2 [1.0-1.4] mg/dL; P <0.001) and high NTproBNP (IV continuous 5,216 [2,599-11,603]; intermittent bolus 4,944 [2,339-9,970]; oral 3,344 [1,570-7,077] pg/mL; P <0.001). There was no difference between IV continuous and intermittent bolus group in weight change, total urine output and change in renal function till 10 days/discharge (adjusted P >0.05 for all). There was no difference in 30 day mortality and HF readmission (adjusted OR 1.08 [95%CI: 0.74, 1.57]; P = 0.701) and 180 days mortality (adjusted OR 1.04 [95%CI: 0.75, 1.43]; P = 0.832).

CONCLUSION

In a large cohort of patients with decompensated HF, there were no significant differences in diuretic-related in-hospital, or post-discharge outcomes between IV continuous and intermittent bolus administration. Tailoring appropriate diuretic strategy to different states of acute HF and congestion phenotypes needs to be further investigated.

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.

Effect of Sotagliflozin on Total Hospitalizations in Patients With Type 2 Diabetes and Worsening Heart Failure : A Randomized Trial

BACKGROUND

In the SOLOIST-WHF (Effect of Sotagliflozin on Cardiovascular Events in Patients With Type 2 Diabetes Post Worsening Heart Failure) trial, sotagliflozin, a sodium-glucose cotransporter-1 and sodium-glucose cotransporter-2 inhibitor, reduced total occurrences of cardiovascular deaths, hospitalizations for heart failure, and urgent visits for heart failure relative to placebo by 33%.

OBJECTIVE

To determine whether sotagliflozin increased the prespecified efficacy outcome of days alive and out of the hospital (DAOH) in the SOLOIST-WHF trial.

DESIGN

Randomized, double-blind, placebo-controlled trial. (ClinicalTrials.gov: NCT03521934).

SETTING

306 sites in 32 countries.

PARTICIPANTS

1222 patients with type 2 diabetes and reduced or preserved ejection fraction who were recently hospitalized for worsening heart failure.

INTERVENTION

200 mg of sotagliflozin once daily (with a possible dose increase to 400 mg) or matching placebo.

MEASUREMENTS

The primary analysis included hospitalizations for any reason on the basis of investigator-reported incidence and duration of admissions after randomization. Days alive and out of the hospital and its converse (days dead and days in the hospital) were analyzed using prespecified Poisson regression models.

RESULTS

Although similar proportions of patients in the sotagliflozin and placebo groups were hospitalized at least once (38.5% vs. 41.4%), fewer patients in the sotagliflozin group were hospitalized more than once (16.3% vs. 22.1%). There were 64 and 76 deaths in the sotagliflozin and placebo groups, respectively. The DAOH rate in the sotagliflozin group was 3% higher than in the placebo group (rate ratio [RR], 1.03 [95% CI, 1.00 to 1.06]; P = 0.027). This difference was primarily driven by a reduction in the rate of days dead (RR, 0.71 [CI, 0.52 to 0.99]; P = 0.041) rather than by a reduction in the rate of days hospitalized for any cause. For every 100 days of follow-up, patients in the sotagliflozin group were alive and out of the hospital for 3% or 2.9 more days than those in the placebo group (91.8 vs. 88.9 days); this difference reflected a 2.6-day difference in days dead (6.3 vs. 8.9 days) and a 0.3-day difference in days in the hospital (1.9 vs. 2.2 days).

LIMITATION

Other than heart failure, the primary reason for each hospitalization was unspecified.

CONCLUSION

Sotagliflozin increased DAOH, a metric that may provide an additional patient-centered outcome to capture the totality of disease burden. Future studies are needed to quantify the consequences of increasing DAOH in terms of health economics and patient quality of life.

PRIMARY FUNDING SOURCE

Sanofi at initiation and Lexicon Pharmaceuticals at completion.

Use of diuretics and outcomes in patients with type 2 diabetes: findings from the EMPA-REG OUTCOME trial

AIMS

Loop diuretics (LD) relieve symptoms and signs of congestion due to heart failure (HF), but many patients prescribed LD do not have such a diagnosis. We studied the relationship between HF diagnosis, use of LD, and outcomes in patients with type 2 diabetes mellitus (T2DM) enrolled in the EMPA-REG OUTCOME trial.

METHODS AND RESULTS

The relationship between HF diagnosis, use of LD, and outcomes was evaluated in four patient subgroups with T2DM: (i) investigator-reported HF on LD, (ii) investigator-reported HF not on LD, (iii) no HF on LD, and (iv) no HF and not on LD, and we assessed their risk of cardiovascular events. Of 7020 participants, 706 (10%) had a diagnosis of HF at baseline, of whom 334 were prescribed LD. However, 755 (11%) patients who did not have a diagnosis of HF were prescribed LD. Compared to those with neither HF nor prescribed LD (reference group; placebo), those with both HF and receiving LD had the highest rates for all-cause [hazard ratio (HR) (95% confidence interval) 3.19 (2.03-5.01)] and cardiovascular mortality [3.83 [(2.28-6.44)], and HF hospitalizations [9.51 (5.61-16.14)]. Patients without HF but prescribed LD had higher rates for all three outcomes [1.62 (1.10-2.39); 1.97 (1.26-3.08); 3.20 (1.90-5.39)], which were similar to patients with HF who were not receiving LD [1.42 (0.78-2.57); 1.56 (0.78-3.11); 3.00 (1.40-6.40)]. Empagliflozin had similar benefits regardless of subgroup (P for interaction >0.1 for all outcomes).

CONCLUSION

Patients with T2DM prescribed LD are at greater risk of cardiovascular events even if they are not reported to have HF; this might reflect under-diagnosis. Empagliflozin was similarly effective in all subgroups investigated.

The Association of COVID-19 With Acute Kidney Injury Independent of Severity of Illness: A Multicenter Cohort Study

RATIONALE & OBJECTIVE

Although coronavirus disease 2019 (COVID-19) has been associated with acute kidney injury (AKI), it is unclear whether this association is independent of traditional risk factors such as hypotension, nephrotoxin exposure, and inflammation. We tested the independent association of COVID-19 with AKI.

STUDY DESIGN

Multicenter, observational, cohort study.

SETTING & PARTICIPANTS

Patients admitted to 1 of 6 hospitals within the Yale New Haven Health System between March 10, 2020, and August 31, 2020, with results for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing via polymerase chain reaction of a nasopharyngeal sample.

EXPOSURE

Positive test for SARS-CoV-2.

OUTCOME

AKI by KDIGO (Kidney Disease: Improving Global Outcomes) criteria.

ANALYTICAL APPROACH

Evaluated the association of COVID-19 with AKI after controlling for time-invariant factors at admission (eg, demographic characteristics, comorbidities) and time-varying factors updated continuously during hospitalization (eg, vital signs, medications, laboratory results, respiratory failure) using time-updated Cox proportional hazard models.

RESULTS

Of the 22,122 patients hospitalized, 2,600 tested positive and 19,522 tested negative for SARS-CoV-2. Compared with patients who tested negative, patients with COVID-19 had more AKI (30.6% vs 18.2%; absolute risk difference, 12.5% [95% CI, 10.6%-14.3%]) and dialysis-requiring AKI (8.5% vs 3.6%) and lower rates of recovery from AKI (58% vs 69.8%). Compared with patients without COVID-19, patients with COVID-19 had higher inflammatory marker levels (C-reactive protein, ferritin) and greater use of vasopressors and diuretic agents. Compared with patients without COVID-19, patients with COVID-19 had a higher rate of AKI in univariable analysis (hazard ratio, 1.84 [95% CI, 1.73-1.95]). In a fully adjusted model controlling for demographic variables, comorbidities, vital signs, medications, and laboratory results, COVID-19 remained associated with a high rate of AKI (adjusted hazard ratio, 1.40 [95% CI, 1.29-1.53]).

LIMITATIONS

Possibility of residual confounding.

CONCLUSIONS

COVID-19 is associated with high rates of AKI not fully explained by adjustment for known risk factors. This suggests the presence of mechanisms of AKI not accounted for in this analysis, which may include a direct effect of COVID-19 on the kidney or other unmeasured mediators. Future studies should evaluate the possible unique pathways by which COVID-19 may cause AKI.

Natriuretic Equation to Predict Loop Diuretic Response in Patients With Heart Failure

BACKGROUND

Most acute decompensated heart failure admissions are driven by congestion. However, residual congestion is common and often driven by the lack of reliable tools to titrate diuretic therapy. The authors previously developed a natriuretic response prediction equation (NRPE), which predicts sodium output using a spot urine sample collected 2 h after loop diuretic administration.

OBJECTIVES

The purpose of this study was to validate the NRPE and describe proof-of-concept that the NRPE can be used to guide diuretic therapy.

METHODS

Two cohorts were assembled: 1) the Diagnosing and Targeting Mechanisms of Diuretic Resistance (MDR) cohort was used to validate the NRPE to predict 6-h sodium output after a loop diuretic, which was defined as poor (<50 mmol), suboptimal (<100 mmol), or excellent (>150 mmol); and 2) the Yale Diuretic Pathway (YDP) cohort, which used the NRPE to guide loop diuretic titration via a nurse-driven automated protocol.

RESULTS

Evaluating 638 loop diuretic administrations, the NRPE showed excellent discrimination with areas under the curve ≥0.90 to predict poor, suboptimal, and excellent natriuretic response, and outperformed clinically obtained net fluid loss (p < 0.05 for all cutpoints). In the YDP cohort (n = 161) using the NRPE to direct therapy mean daily urine output (1.8 ± 0.9 l vs. 3.0 ± 0.8 l), net fluid output (-1.1 ± 0.9 l vs. -2.1 ± 0.9 l), and weight loss (-0.3 ± 0.3 kg vs. -2.5 ± 0.3 kg) improved substantially following initiation of the YDP (p < 0.001 for all pre-post comparisons).

CONCLUSIONS

Natriuretic response can be rapidly and accurately predicted by the NRPE, and this information can be used to guide diuretic therapy during acute decompensated heart failure. Additional study of diuresis guided by the NRPE is warranted.

Sotagliflozin in Patients with Diabetes and Recent Worsening Heart Failure

BACKGROUND

Sodium-glucose cotransporter 2 (SGLT2) inhibitors reduce the risk of hospitalization for heart failure or death from cardiovascular causes among patients with stable heart failure. However, the safety and efficacy of SGLT2 inhibitors when initiated soon after an episode of decompensated heart failure are unknown.

METHODS

We performed a multicenter, double-blind trial in which patients with type 2 diabetes mellitus who were recently hospitalized for worsening heart failure were randomly assigned to receive sotagliflozin or placebo. The primary end point was the total number of deaths from cardiovascular causes and hospitalizations and urgent visits for heart failure (first and subsequent events). The trial ended early because of loss of funding from the sponsor.

RESULTS

A total of 1222 patients underwent randomization (608 to the sotagliflozin group and 614 to the placebo group) and were followed for a median of 9.0 months; the first dose of sotagliflozin or placebo was administered before discharge in 48.8% and a median of 2 days after discharge in 51.2%. Among these patients, 600 primary end-point events occurred (245 in the sotagliflozin group and 355 in the placebo group). The rate (the number of events per 100 patient-years) of primary end-point events was lower in the sotagliflozin group than in the placebo group (51.0 vs. 76.3; hazard ratio, 0.67; 95% confidence interval [CI], 0.52 to 0.85; P<0.001). The rate of death from cardiovascular causes was 10.6 in the sotagliflozin group and 12.5 in the placebo group (hazard ratio, 0.84; 95% CI, 0.58 to 1.22); the rate of death from any cause was 13.5 in the sotagliflozin group and 16.3 in the placebo group (hazard ratio, 0.82; 95% CI, 0.59 to 1.14). Diarrhea was more common with sotagliflozin than with placebo (6.1% vs. 3.4%), as was severe hypoglycemia (1.5% vs. 0.3%). The percentage of patients with hypotension was similar in the sotagliflozin group and the placebo group (6.0% and 4.6%, respectively), as was the percentage with acute kidney injury (4.1% and 4.4%, respectively). The benefits of sotagliflozin were consistent in the prespecified subgroups of patients stratified according to the timing of the first dose.

CONCLUSIONS

In patients with diabetes and recent worsening heart failure, sotagliflozin therapy, initiated before or shortly after discharge, resulted in a significantly lower total number of deaths from cardiovascular causes and hospitalizations and urgent visits for heart failure than placebo. (Funded by Sanofi and Lexicon Pharmaceuticals; SOLOIST-WHF ClinicalTrials.gov number, NCT03521934.).