The value of urinary sodium assessment in acute heart failure

Diuretic Strategies in Acute Decompensated Heart Failure: A Narrative Review

Background

Heart failure is a common condition with considerable associated costs, morbidity, and mortality. Patients often present to hospital with dyspnea and edema. Inadequate inpatient decongestion is an important contributor to high readmission rates. There is little evidence concerning diuresis to guide clinicians in caring for patients with acute decompensated heart failure. Contemporary diuretic strategies have been defined by expert opinion and older landmark clinical trials.

Objective

To present a narrative review of contemporary recommendations, along with their underlying evidence and pharmacologic rationale, for diuretic strategies in inpatients with acute decompensated heart failure.

Data Sources

PubMed, OVID, and Embase databases were searched from inception to December 22, 2022, with the following search terms: heart failure, acute heart failure, decompensated heart failure, furosemide, bumetanide, ethacrynic acid, hydrochlorothiazide, indapamide, metolazone, chlorthalidone, spironolactone, eplerenone, and acetazolamide.

Study Selection

Randomized controlled trials and systematic reviews involving at least 100 adult patients (> 18 years) were included. Trials involving torsemide, chlorothiazide, and tolvaptan were excluded.

Data Synthesis

Early, aggressive administration of a loop diuretic has been associated with expedited symptom resolution, shorter length of stay, and possibly reduced mortality. Guidelines make recommendations about dose and frequency but do not recommend any particular loop diuretic over another; however, furosemide is most commonly used. Guidelines recommend that the initial furosemide dose (on admission) be 2-2.5 times the patient's home dose. A satisfactory diuretic response can be defined as spot urine sodium content greater than 50-70 mmol/L at 2 hours; urine output greater than 100-150 mL/h in the first 6 hours or 3-5 L in 24 hours; or a change in weight of 0.5-1.5 kg in 24 hours. If congestion persists after the maximization of loop diuretic therapy over the first 24-48 hours, an adjunctive diuretic such as thiazide or acetazolamide should be added. If decongestion targets are not met, continuous infusion of furosemide may be considered.

Conclusions

Heart failure with congestion can be managed with careful administration of high-dose loop diuretics, supported by thiazides and acetazolamide when necessary. Clinical trials are underway to further evaluate this strategy.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Spot urinary sodium as a prognostic marker for mortality in patients with acute decompensated heart failure

Introduction. Urinary sodium has been proposed as a prognostic marker and indicator of the diuretic response in patients with heart failure. However, study results are heterogeneous. Objective. To evaluate the spot urinary sodium level as a risk factor for mortality in patients with decompensated heart failure. Materials and methods. We conducted a case-control study nested in a prospective cohort of patients with decompensated heart failure. The primary outcome was mortality at 180 days. The risk factors associated with mortality were evaluated through a bivariate analysis. Differences in clinical variables between groups with urinary sodium greater than or lesser than 70 mEq/L were analyzed. Results. The study included 79 patients; 15 died at 180 days. Their mean age was 68.9 years (SD=± 13.8); 30 were women (38%), and 15 (18.9%) had urinary sodium <70 mEq/L. In the bivariate analysis, a significant association was found between mortality and past medical history of hospitalizations, SBP<90 mm Hg, the use of inotropes, and urinary sodium <70 mEq/L. Regarding clinical characteristics, patients with low urinary sodium level in the last year were hospitalized more frequently with hyponatremia and hypotension at admission. Conclusion. Patients with urinary sodium <70 mEq/L had more severe signs. In a bivariate analysis, urinary sodium was associated with mortality at 180 days.

Peritoneal and Urinary Sodium Removal in Refractory Congestive Heart Failure Patients Included in an Ambulatory Peritoneal Dialysis Program: Valuable for Monitoring the Course of the Disease

INTRODUCTION

Spot urinary sodium emerged as a useful parameter for assessing decongestion in patients with congestive heart failure (CHF). Growing evidence endorses the therapeutic role of continuous ambulatory peritoneal dialysis (CAPD) in patients with refractory CHF and kidney disease. We aimed to examine the long-term trajectory of urinary, peritoneal, and total (urinary plus peritoneal) sodium removal in a cohort of patients with refractory CHF enrolled in a CAPD program. Additionally, we explored whether sodium removal was associated with the risk of long-term mortality and episodes of worsening heart failure (WHF).

METHODS

We included 66 ambulatory patients with refractory CHF enrolled in a CAPD program in a single teaching center. 24-h peritoneal, urinary, and total sodium elimination were analyzed at baseline and after CAPD initiation. Its trajectories over time were calculated using joint modeling of longitudinal and survival data. Within the framework of joint frailty models for recurrent and terminal events, we estimated its prognostic effect on recurrent episodes of WHF.

RESULTS

At the time of enrollment, the mean age and estimated glomerular filtration rate were 72.8 ± 8.4 years and 28.5 ± 14.3 mL/min/1.73 m2, respectively. The median urinary sodium at baseline was 2.34 g/day (1.40-3.55). At a median (p25%-p75%) follow-up of 2.93 (1.93-3.72) years, we registered 0.28 deaths and 0.24 episodes of WHF per 1 person-year. Compared to baseline (urinary), CAPD led to increased sodium excretion (urinary plus dialyzed) since the first follow-up visit (p < 0.001). Over the follow-up, repeated measurements of total sodium removal were associated with a lower risk of death and episodes of WHF.

CONCLUSIONS

CAPD increased sodium removal in patients with refractory CHF. Elevated sodium removal identified those patients with a lower risk of death and episodes of WHF.

Cardiovascular and renal effects of SGLT2 inhibitor initiation in acute heart failure: a meta-analysis of randomized controlled trials

BACKGROUND

We sought to compare cardiovascular outcomes, renal function, and diuresis in patients receiving standard diuretic therapy for acute heart failure (AHF) with or without the addition of SGLT2i.

METHODS AND RESULTS

Systematic search of three electronic databases identified nine eligible randomized controlled trials involving 2,824 patients. The addition of SGLT2i to conventional therapy for AHF reduced all-cause death (odds ratio [OR] 0.75; 95% CI 0.56-0.99; p = 0.049), readmissions for heart failure (HF) (OR 0.54; 95% CI 0.44-0.66; p < 0.001), and the composite of cardiovascular death and readmissions for HF (hazard ratio 0.71; 95% CI 0.60-0.84; p < 0.001). Furthermore, SGLT2i increased mean daily urinary output in liters (mean difference [MD] 0.45; 95% CI 0.03-0.87; p = 0.035) and decreased mean daily doses of loop diuretics in mg of furosemide equivalent (MD -34.90; 95% CI [- 52.58, - 17.21]; p < 0.001) without increasing the incidence worsening renal function (OR 0.75; 95% CI 0.43-1.29; p = 0.290).

CONCLUSION

SGLT2i addition to conventional diuretic therapy reduced all-cause death, readmissions for HF, and the composite of cardiovascular death or readmissions for HF. Moreover, SGLT2i was associated with a higher volume of diuresis with a lower dose of loop diuretics.

The Prognostic Role of Spot Urinary Sodium and Chloride in a Cohort of Hospitalized Advanced Heart Failure Patients: A Pilot Study

Recent studies have demonstrated the prognostic value of spot urinary sodium (UNa+) in acutely decompensated chronic HF (ADCHF) patients. However, data on the prognostic role of UNa+ and spot urinary chloride (UCl-) in patients with advanced HF are limited. In the present prospective pilot study, we examined the predictive value of UNa+ and UCl- concentration at baseline, at 2 h and at 24 h after admission for all-cause mortality and HF rehospitalization up to 3 months post-discharge. Consecutive advanced HF patients (n = 30) admitted with ADCHF and aged > 18 years were included in the study. Loop diuretics were administered based on the natriuresis-guided algorithm recommended by the recent HF guidelines. Exclusion criteria were cardiogenic shock, acute coronary syndrome, estimated glomerular filtration rate < 15 mL/min/1.73 m2, severe hepatic dysfunction (Child-Pugh category C), and sepsis. UNa+ at baseline (Area Under the Curve (AUC) = 0.75, 95% Confidence Interval (CI) (0.58-0.93), p = 0.019) and at 2 h after admission (AUC = 0.80, 95% CI: 0.64-0.96, p = 0.005) showed good and excellent discrimination, respectively. UCl- at 2 h after admission (AUC = 0.75, 95%CI (0.57-0.93), p = 0.017) demonstrated good discrimination. In the multivariate logistic regression analysis, UNa+ at 2 h (p = 0.02) and dose of loop diuretics at admission (p = 0.03) were the only factors independently associated with the study outcome. In conclusion, UNa+ and UCl- may have a prognostic role in hospitalized advanced HF patients.

Spot Urinary Sodium Measurements: the Future Direction of the Treatment and Follow-up of Patients with Heart Failure

PURPOSE OF REVIEW

Heart failure is characterized by episodes of congestion with need for hospitalization. The current metrics lack the accuracy to predict and prevent episodes of congestion and to guide diuretic titration to reach euvolemia in case of decompensation. This article aims to provide answers to the role of urinary sodium measurements in acute and chronic heart failure.

RECENT FINDINGS

In acute heart failure, urinary sodium concentrations at the moment of admission and after diuretic administration are correlated with short- and long-term outcome. As this is a reflection of the degree of sodium retention, it can be used as a guide in the diuretic titration. In chronic heart failure, it might be used to predict and consequently prevent episodes of decompensation. Urinary sodium measurements hold great promises to be a novel diagnostic and therapeutic parameter in patients with acute and chronic heart failure. However, more research is needed.

Natriuresis as a Way to Assess the Effectiveness of Diuretic Therapy for Acute Decompensated Heart Failure: Data from a Pilot Study

Aim. To analyze the clinical significance of the sodium level in a single urine test obtained 2 hours after the first dose of a loop diuretic was administered in patients with acute decompensation of chronic heart failure (ADHF).

Material and methods. An observational study was conducted on the basis of a rapid-care hospital. The concentration of sodium in urine analysis obtained 2 hours after intravenous administration of the first dose of loop diuretic and natriuresis for the first day of hospitalization were evaluated. The development of resistance to diuretics was taken as the primary endpoint (the need to increase the daily dose of furosemide by more than 2 times compared to the initial one or the addition of another class of diuretic drugs).

Results. 25 patients with ADHF were included. The average age of patients was 69.0±14.8 years, 16 (64%) of them were men. The average left ventricular ejection fraction was 49.0±13.5%. The level of the N‐terminal fragment of the brain natriuretic peptide (NT-proBNP) was 3416 (2128; 5781) pg/ml. The average sodium concentration in the urine analysis obtained 2 hours after the start of treatment was 100.6±41.0 mmol / l. The concentration of sodium in urine for the first day was 102.2±39.0 mmol/l. 2 hours after the start of treatment, the sodium concentration in a single urine test was less than 50 mmol/l in 5 (20%) patients. Upon further observation, oligoanuria (defined as diuresis of less than 400 ml within 24 hours) developed in 2 of them. Oligoanuria was not detected among patients whose sodium concentration was more than 50 mmol/l. The need for escalation (any increase in the dose of a loop diuretic and/or the addition of another class of diuretic drugs) arose in 7 (28%) patients; at the same time, we diagnosed the development of resistance to diuretics in 5 (20%) of them. Resistance to diuretics was more common among patients with a sodium concentration in a single urine test obtained 2 hours after the start of furosemide administration, less than 50 mmol/l (p=0.037); when dividing the recruited patient population into subgroups with a sodium concentration in a single urine test ≥50 mmol/l and <50 mmol/l there was no significant difference in the need for any escalation of diuretic therapy [3 (60%) vs 4 (20%), p=0.07].

Conclusion. Resistance to diuretics is more common among patients with a sodium concentration in a single urine test obtained 2 hours after the first dose of furosemide, less than 50 mmol / l. Evaluation of natriuresis allows to identify insufficient effectiveness of diuretic therapy already at the beginning of treatment.

The association between urinary sodium concentration (UNa) and outcomes of acute heart failure: a systematic review and meta-analysis

AIMS

Urinary sodium concentration (UNa) is a simple test advocated to assess diuretics efficacy and predict outcomes in acute heart failure (AHF). We performed a systematic review and meta-analysis to examine the association of UNa with outcomes of AHF.

METHODS AND RESULTS

We searched Embase and Medline for eligible studies that reported the association between UNa and outcomes of urinary output, weight loss, worsening renal function, length of hospital stay, re-hospitalization, worsening heart failure, and all-cause mortality in AHF. Nineteen observational studies out of 1592 screened records were included. For meta-analyses of outcomes, we grouped patients into high vs. low UNa, with most studies defining high UNa as &gt;48-65 mmol/L. In the high UNa group, pooled data showed a higher urinary output (mean difference 502 mL, 95% CI 323-681, P &lt; 0.01), greater weight loss (mean difference 1.6 kg, 95% CI 0.3-2.9, P = 0.01), and a shorter length of stay (mean difference -1.4 days, 95% CI -2.8 to -0.1, P = 0.03). There was no significant difference in worsening kidney function (OR 0.54, 95% CI 0.25-1.16, P = 0.1). Due to the small number of studies, we did not report pooled estimates for re-hospitalization and worsening heart failure. High UNa was associated with lower odds of 30-day (OR 0.27; 95% CI 0.14-0.49, P &lt; 0.01), 90-day (OR 0.39,95% CI 0.25-0.59, P &lt; 0.01) and 12-month (OR 0.35; 95% CI 0.20-0.61, P &lt; 0.01) mortality.

CONCLUSION

High UNa after diuretic administration is associated with higher urinary output, greater weight loss, shorter length of stay, and lower odds of death. UNa is a promising marker of diuretic efficacy in AHF which should be confirmed in randomized trials.

Acetazolamide in Acute Decompensated Heart Failure with Volume Overload

BACKGROUND

Whether acetazolamide, a carbonic anhydrase inhibitor that reduces proximal tubular sodium reabsorption, can improve the efficiency of loop diuretics, potentially leading to more and faster decongestion in patients with acute decompensated heart failure with volume overload, is unclear.

METHODS

In this multicenter, parallel-group, double-blind, randomized, placebo-controlled trial, we assigned patients with acute decompensated heart failure, clinical signs of volume overload (i.e., edema, pleural effusion, or ascites), and an N-terminal pro-B-type natriuretic peptide level of more than 1000 pg per milliliter or a B-type natriuretic peptide level of more than 250 pg per milliliter to receive either intravenous acetazolamide (500 mg once daily) or placebo added to standardized intravenous loop diuretics (at a dose equivalent to twice the oral maintenance dose). Randomization was stratified according to the left ventricular ejection fraction (≤40% or >40%). The primary end point was successful decongestion, defined as the absence of signs of volume overload, within 3 days after randomization and without an indication for escalation of decongestive therapy. Secondary end points included a composite of death from any cause or rehospitalization for heart failure during 3 months of follow-up. Safety was also assessed.

RESULTS

A total of 519 patients underwent randomization. Successful decongestion occurred in 108 of 256 patients (42.2%) in the acetazolamide group and in 79 of 259 (30.5%) in the placebo group (risk ratio, 1.46; 95% confidence interval [CI], 1.17 to 1.82; P<0.001). Death from any cause or rehospitalization for heart failure occurred in 76 of 256 patients (29.7%) in the acetazolamide group and in 72 of 259 patients (27.8%) in the placebo group (hazard ratio, 1.07; 95% CI, 0.78 to 1.48). Acetazolamide treatment was associated with higher cumulative urine output and natriuresis, findings consistent with better diuretic efficiency. The incidence of worsening kidney function, hypokalemia, hypotension, and adverse events was similar in the two groups.

CONCLUSIONS

The addition of acetazolamide to loop diuretic therapy in patients with acute decompensated heart failure resulted in a greater incidence of successful decongestion. (Funded by the Belgian Health Care Knowledge Center; ADVOR ClinicalTrials.gov number, NCT03505788.).

PoCUS in nephrology: a new tool to improve our diagnostic skills

Point-of-Care Ultrasonography (PoCUS) aims to include a fifth pillar (insonation) in the classical physical examination in order to obtain images to answer specific questions by the clinician at the patient's bedside, allowing rapid identification of structural or functional abnormalities, enabling more accurate volume assessment and supporting diagnosis, as well as guiding procedures. In recent years, PoCUS has started becoming a valuable tool in day-to-day clinical practice, adopted by healthcare professionals from various medical specialties, never replacing physical examination but improving patient and medical care and experience. Renal patients represent a wide range of diseases, which lends PoCUS a special role as a valuable tool in different scenarios, not only for volume-related information but also for the assessment of a wide range of acute and chronic conditions, enhancing the sensitivity of conventional physical examination in nephrology. PoCUS in the hands of a nephrologist is a precision medicine tool.

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.

Dose of furosemide before admission predicts diuretic efficiency and long-term prognosis in acute heart failure

AIMS

The outpatient diuretic dose is a marker of diuretic resistance and prognosis in chronic heart failure (HF). Still, the impact of the preadmission dose on diuretic efficiency (DE) and prognosis in acute HF is not fully known.

METHODS AND RESULTS

We conducted an observational and prospective study. All patients admitted for acute HF treated with intravenous diuretic and at least one criterion of congestion on admission were evaluated. Decongestion [physical examination, hemoconcentration, N-terminal pro-brain natriuretic peptide (NT-proBNP) change, and lung ultrasound], DE (weight loss and urine output per unit of 40 mg furosemide), and urinary sodium were monitored on the fifth day of admission. DE was dichotomized into high-low based on the median value. A multivariate Cox regression analysis was conducted to find predictors of HF readmission or mortality. A total of 105 patients were included between July 2017 and July 2019. Mean age was 74.5 ± 12.0 years, 64.8% were male, 33.3% had de novo HF, and mean left ventricular ejection fraction was 46 ± 17%. Median follow-up was 26 [15-35] months. Low DE based on weight loss was associated with a higher previous dose of furosemide (odds ratio [OR] 1.01 [1.00-1.02]), thiazide treatment before admission (OR 9.37 [2.19-40.14]), and lower diastolic blood pressure (OR 0.95 [0.91-0.98]) in the multivariate regression model. Only previous dose of furosemide (OR 1.01 [1.00-1.02]) and haemoglobin at admission (OR 0.76 [0.58-0.99]) were associated with low DE based on urine output in the multivariate analysis. The correlation between the previous dose of furosemide and DE based on weight loss was poor (r = -0.12; P = 0.209) and with DE based on urine output was weak to moderate (r = -0.33; P < 0.001). Low DE based on weight loss and urine output was associated with lesser decongestion measured by NT-proBNP (P = 0.011; P = 0.007), hemoconcentration (P = 0.006; P = 0.044), and lung ultrasound (P = 0.034; P = 0.029), but not by physical examination (P = 0.506; P = 0.560). Survival and event-free survival in acute decompensated HF (ADHF) were lower than in de novo HF; a preadmission dose of furosemide > 80 mg in ADHF identified patients with particularly poor prognosis (log-rank < 0.001). In ADHF, the preadmission dose of furosemide (hazard ratio [HR] 1.34 [1.08-1.67] per 40 mg) and NT-proBNP at admission (HR 1.03 [1.01-1.06] per 1000 pg/mL) were independently associated with mortality or HF readmission in the multivariate Cox regression analysis.

CONCLUSIONS

The outpatient dose of furosemide before acute HF admission predicts DE and must be taken into account when deciding on the initial diuretic dose. In ADHF, the outpatient dose of furosemide can predict long-term prognosis better than DE during hospitalization.

The year in cardiovascular medicine 2021: heart failure and cardiomyopathies

In the year 2021, the universal definition and classification of heart failure (HF) was published that defines HF as a clinical syndrome with symptoms and/or signs caused by a cardiac abnormality and corroborated by elevated natriuretic peptide levels or objective evidence of cardiogenic congestion. This definition and the classification of HF with reduced ejection fraction (HFrEF), mildly reduced, and HF with preserved ejection fraction (HFpEF) is consistent with the 2021 ESC Guidelines on HF. Among several other new recommendations, these guidelines give a Class I indication for the use of the sodium–glucose co-transporter 2 (SGLT2) inhibitors dapagliflozin and empagliflozin in HFrEF patients. As the first evidence-based treatment for HFpEF, in the EMPEROR-Preserved trial, empagliflozin reduced the composite endpoint of cardiovascular death and HF hospitalizations. Several reports in 2021 have provided novel and detailed analyses of device and medical therapy in HF, especially regarding sacubitril/valsartan, SGLT2 inhibitors, mineralocorticoid receptor antagonists, ferric carboxymaltose, soluble guanylate cyclase activators, and cardiac myosin activators. In patients hospitalized with COVID-19, acute HF and myocardial injury is quite frequent, whereas myocarditis and long-term damage to the heart are rather uncommon.

Distinct renin/aldosterone activity profiles correlate with renal function, natriuretic response, decongestive ability and prognosis in acute heart failure

BACKGROUND

Although renin-angiotensin-aldosterone system (RAAS) activation is believed to be the major driver of acute heart failure (AHF) episodes our understanding of its prevalence and clinical relevance in contemporary settings is incomplete.

METHODS

Serum renin and aldosterone were measured at day-1 and at discharge in patients (n = 211) that were hospitalized between 2016 and 2017 for AHF in a single cardiology center. The population was profiled based on upper limits of normal (ULN) of both biomarkers assessed at day-1 and linked with the clinical course and outcomes.

RESULTS

The study population constituted of three profiles: RAAS-/- (n = 121 [57%]); RAAS+/- (n = 60 [28%]); and RAAS+/+ (n = 30 [14%]). The RAAS+/+ profile had the lowest blood pressure and serum sodium at admission, day-2 and discharge compared to the other profiles (p < 0.001). The RAAS+/+ patients had significantly lower urine Na+ at admission (57.8 ± 36.7 vs 97.3 ± 31.3 and 86.4 ± 35.0), day-1 (52.7 ± 32.7 vs 85.3 ± 36.3 and 75.5 ± 33.9) mmol/l, vs RAAS-/- and RAAS+/- profiles, respectively, all p < 0.001. There was also a gradual decrease of renal function across increasing RAAS profiles. The RAAS+/+ profile received higher dose of furosemide at discharge 120 [80-160] vs the other profiles 80 [40-120] mg, p < 0.01. The risks of one year mortality or HF rehospitalization increased across the RAAS profiles (p < 0.001). The trajectory of renin or aldosterone change during hospitalization was not related to outcomes.

CONCLUSIONS

The RAAS overactivity is not essential for development of AHF. However, elevated RAAS is a marker of more advanced stages of heart failure, is related to low natriuresis and adverse clinical outcomes.

Rationale and Design of the Efficacy of a Standardized Diuretic Protocol in Acute Heart Failure Study

Aims

Although acute heart failure (AHF) with volume overload is treated with loop diuretics, their dosing and type of administration are mainly based upon expert opinion. A recent position paper from the Heart Failure Association (HFA) proposed a step‐wise pharmacologic diuretic strategy to increase the diuretic response and to achieve rapid decongestion. However, no study has evaluated this protocol prospectively.

Methods and results

The Efficacy of a Standardized Diuretic Protocol in Acute Heart Failure (ENACT‐HF) study is an international, multicentre, non‐randomized, open‐label, pragmatic study in AHF patients on chronic loop diuretic therapy, admitted to the hospital for intravenous loop diuretic therapy, aiming to enrol 500 patients. Inclusion criteria are as follows: at least one sign of volume overload (oedema, ascites, or pleural effusion), use ≥ 40 mg of furosemide or equivalent for >1 month, and a BNP > 250 ng/L or an N‐terminal pro‐B‐type natriuretic peptide > 1000 pg/L. The study is designed in two sequential phases. During Phase 1, all centres will treat consecutive patients according to the local standard of care. In the Phase 2 of the study, all centres will implement a standardized diuretic protocol in the next cohort of consecutive patients. The protocol is based upon the recently published HFA algorithm on diuretic use and starts with intravenous administration of two times the oral home dose. It includes early assessment of diuretic response with a spot urinary sodium measurement after 2 h and urine output after 6 h. Diuretics will be tailored further based upon these measurements. The study is powered for its primary endpoint of natriuresis after 1 day and will be able to detect a 15% difference with 80% power. Secondary endpoints are natriuresis and diuresis after 2 days, change in congestion score, change in weight, in‐hospital mortality, and length of hospitalization.

Conclusions

The ENACT‐HF study will investigate whether a step‐wise diuretic approach, based upon early assessment of urinary sodium and urine output as proposed by the HFA, is feasible and able to improve decongestion in AHF with volume overload.

Metabolic maturation during postnatal right ventricular development switches to heart-contraction regulation due to volume overload

BACKGROUND

Metabolic maturation is one of the primary processes of postnatal cardiomyocyte development. How volume overload (VO), a pathological state of the right ventricle (RV) in children with congenital heart disease (CHD) and patients with heart failure, affects cardiomyocyte metabolic maturation is unclear.

METHODS AND RESULTS

A fistula between the abdominal aorta and inferior vena cava on postnatal day 7 (P7) was created in a mouse model to induce a young-aged RV VO. RNA sequencing revealed that the most enriched gene ontology (GO) terms of the upregulated transcriptome had been changed from metabolic maturation to heart contraction by VO. Transmission electron microscopy imaging showed that metabolic maturation marker-mitochondria were converted into the maturation style in the sham group while remaining unchanged in VO group. Calcium imaging showed that the calcium handling ability had slightly increased in the sham group but dramatically increased in the VO group, even with irregular contraction. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the top three enriched KEGG pathways for the upregulated transcriptome during normal RV development were the citrate cycle, cardiac muscle contraction, and protein processing in the endoplasmic reticulum. VO changed those to arrhythmogenic RV cardiomyopathy, dilated cardiomyopathy, and hypertrophic cardiomyopathy.

CONCLUSIONS

Metabolic maturation of postnatal RV development was partly interrupted by VO, and the underlining mechanism was associated with the activation of cardiomyopathy pathways.

Acute heart failure in elderly patients: a review of invasive and non-invasive management

Acute heart failure (AHF) is a major cause of unplanned hospitalisations in the elderly and is associated with high mortality. Its prevalence has grown in the last years due to population aging and longer life expectancy of chronic heart failure patients. Although international societies have provided guidelines for the management of AHF in the general population, scientific evidence for geriatric patients is often lacking, as these are underrepresented in clinical trials. Elderly have a different risk profile with more comorbidities, disability, and frailty, leading to increased morbidity, longer recovery time, higher readmission rates, and higher mortality. Furthermore, therapeutic options are often limited, due to unfeasibility of invasive strategies, mechanical circulatory support and cardiac transplantation. Thus, the in-hospital management of AHF should be tailored to each patient's clinical situation, cardiopulmonary condition and geriatric assessment. Palliative care should be considered in some cases, in order to avoid unnecessary diagnostics and/or treatments. After discharge, a strict follow-up through outpatient clinic or telemedicine is can improve quality of life and reduce rehospitalisation rates. The aim of this review is to offer an insight on current literature and provide a clinically oriented, patient-tailored approach regarding assessment, treatment and follow-up of elderly patients admitted for AHF.

Spot urine sodium in acute heart failure: differences in prognostic value on admission and discharge

AIMS

Most studies examined spot urine sodium's (sUNa⁺ ) prognostic utility during the early phase of acute heart failure (AHF) hospitalization. In AHF, sodium excretion is related to clinical status; therefore, we investigated the differences in the prognostic information of spot UNa⁺ throughout the course of hospitalization for AHF (admission vs. discharge).

METHODS AND RESULTS

The study population were AHF patients (n = 172), who survived the index hospitalization. We compared the relationship between early (on admission, at 24 and 48 h) and discharge sUNa⁺ measurements with post-discharge study endpoints: composite of 1 year all-cause mortality and AHF rehospitalization (with time to first event analysis) as well as with each event in separation. There were 49 (28.5%) deaths, 40 (23.3%) AHF rehospitalizations, while the composite endpoint occurred in 69 (40.1%) during 1 year follow-up. The sUNa⁺ had prognostic significance for the composite endpoint when assessed on admission, at 24 and at 48 h: hazard ratios (HRs) with 95% confidence intervals (CIs) (per 10 mmol/L) were 0.88 (0.82-0.94); 0.87 (0.81-0.91); 0.90 (0.84-0.96), all P < 0.005. In contrast to early, active decongestion phase, discharge sUNa⁺ had no prognostic significance HR (95% CI) (per 10 mmol/L): 0.99 (0.93-1.06) P = 0.79 for the composite endpoint, which was independent from the dose of oral furosemide prescribed at that timepoint (average causal mediation effects: -0.38; P = 0.71). Similarly, discharge sUNa⁺ was neither associated with 1 year mortality HR (95% CI) (per 10 mmol/L): 0.97 (0.89-1.05) P = 0.48 nor with AHF rehospitalizations HR (95% CI) (per 10 mmol/l): 1.03 (0.94-1.12), P = 0.56. The comparison of longitudinal profiles of sUNa⁺ during hospitalization showed significantly higher values within the early, active decongestive phase in those who did not experience composite endpoint when compared with those who did: admission: 94 ± 34 vs. 76 ± 35; Day 1: 85 ± 36 vs. 65 ± 37; Day 2: 84 ± 37 vs. 67 ± 35, all P < 0.005 (mmol/L), respectively. There was no difference between those groups in discharge sUNa⁺ : 73 ± 35 vs. 70 ± 35 P = 0.82 (mmol/L).

CONCLUSIONS

Spot UNa⁺ assessed at early phase of hospitalization and at discharge have different prognostic significance, which confirms that it should be always interpreted along with clinical context.

Diuretic response and effects of diuretic omission in ambulatory heart failure patients on chronic low-dose loop diuretic therapy

AIMS

To study loop diuretic response and effect of loop diuretic omission in ambulatory heart failure (HF) patients on chronic low-dose loop diuretics.

METHODS AND RESULTS

Urine collections were performed on two consecutive days in 40 ambulatory HF patients with 40-80 mg furosemide (day 1 with loop diuretic; day 2 without loop diuretic). Three phases were collected each day: (i) first 6 h; (ii) rest of the day; and (iii) night. On the day of loop diuretic intake, the total natriuresis was 125.9 (86.9-155.0) mmol/24 h and urine output was 1650 (1380-2025) mL/24 h. There was a clear loop diuretic response with a natriuresis of 9.4 (6.7-15.9) mmol/h and a urine output of 117 (83-167) mL/h during the first 6 h, followed by a significant drop in natriuresis and urine output during the rest of the day [2.6 (1.8-4.8) mmol/h and 55 (33-71) mL/h] and night [2.2 (1.6-3.5) mmol/h and 44 (34-73) mL/h]. On day 2, after loop diuretic omission, the natriuresis and urine output remained similarly low the entire day, resulting in a 50% reduction in natriuresis [55.1 (33.5-77.7) mmol/24 h; P < 0.001] and a 31% reduction in urine output [1035 (875-1425) mL/24 h; P < 0.001] compared with the day of loop diuretic intake.

CONCLUSION

Patients with HF on chronic loop diuretic treatment still have a clear diuretic response phase, while loop diuretic omission leads to a significant drop in natriuresis and urine output, arguing against routine cessation of low-dose loop diuretics.