Acetazolamide As A Valuable Addition to Acute Heart Failure?

Consider IV Acetazolamide in addition to standard IV loop diuretic therapy in patients hospitalized for acute decompensated heart failure.1.

Continuous infusion versus bolus injection of loop diuretics for acute heart failure.

BACKGROUND: Acute heart failure (AHF) is new onset of, or a sudden worsening of, chronic heart failure characterised by congestion in about 95% of cases or end-organ hypoperfusion in 5% of cases. Treatment often requires urgent escalation of diuretic therapy, mainly through hospitalisation. This Cochrane review evaluated the efficacy of intravenous loop diuretics strategies in treating AHF in individuals with New York Heart Association (NYHA) classification III or IV and fluid overload. OBJECTIVES: To assess the effects of intravenous continuous infusion versus bolus injection of loop diuretics for the initial treatment of acute heart failure in adults. SEARCH METHODS: We identified trials through systematic searches of bibliographic databases and in clinical trials registers including CENTRAL, MEDLINE, Embase, CPCI-S on the Web of Science, ClinicalTrials.gov, the World Health Organization (WHO) International Clinical Trials Registry platform (ICTRP), and the European Union Trials register. We conducted reference checking and citation searching, and contacted study authors to identify additional studies. The latest search was performed on 29 February 2024. SELECTION CRITERIA: We included randomised controlled trials (RCTs) involving adults with AHF, NYHA classification III or IV, regardless of aetiology or ejection fraction, where trials compared intravenous continuous infusion of loop diuretics with intermittent bolus injection in AHF. We excluded trials with chronic stable heart failure, cardiogenic shock, renal artery stenosis, or end-stage renal disease. Additionally, we excluded studies combining loop diuretics with hypertonic saline, inotropes, vasoactive medications, or renal replacement therapy and trials where diuretic dosing was protocol-driven to achieve a target urine output, due to confounding factors. DATA COLLECTION AND ANALYSIS: Two review authors independently screened papers for inclusion and reviewed full-texts. Outcomes included weight loss, all-cause mortality, length of hospital stay, readmission following discharge, and occurrence of acute kidney injury. We performed risk of bias assessment and meta-analysis where data permitted and assessed certainty of the evidence. MAIN RESULTS: The review included seven RCTs, spanning 32 hospitals in seven countries in North America, Europe, and Asia. Data collection ranged from eight months to six years. Following exclusion of participants in subgroups with confounding treatments and different clinical settings, 681 participants were eligible for review. These additional study characteristics, coupled with our strict inclusion and exclusion criteria, improve the applicability of the body of the evidence as they reflect real-world clinical practice. Meta-analysis was feasible for net weight loss, all-cause mortality, length of hospital stay, readmission, and acute kidney injury. Literature review and narrative analysis explored daily fluid balance; cardiovascular mortality; B-type natriuretic peptide (BNP) change; N-terminal-proBNP change; and adverse incidents such as ototoxicity, hypotension, and electrolyte imbalances. Risk of bias assessment revealed two studies with low overall risk, four with some concerns, and one with high risk. All sensitivity analyses excluded trials at high risk of bias. Only narrative analysis was conducted for 'daily fluid balance' due to diverse data presentation methods across two studies (169 participants, the evidence was very uncertain about the effect). Results of narrative analysis varied. For instance, one study reported higher daily fluid balance within the first 24 hours in the continuous infusion group compared to the bolus injection group, whereas there was no difference in fluid balance beyond this time point. Continuous intravenous infusion of loop diuretics may result in mean net weight loss of 0.86 kg more than bolus injection of loop diuretics, but the evidence is very uncertain (mean difference (MD) 0.86 kg, 95% confidence interval (CI) 0.44 to 1.28; 5 trials, 497 participants; P < 0.001, I2 = 21%; very low-certainty evidence). Importantly, sensitivity analysis excluding trials with high risk of bias showed there was insufficient evidence for a difference in bodyweight loss between groups (MD 0.70 kg, 95% CI -0.06 to 1.46; 3 trials, 378 participants; P = 0.07, I2 = 0%). There may be little to no difference in all-cause mortality between continuous infusion and bolus injection (risk ratio (RR) 1.53, 95% CI 0.81 to 2.90; 5 trials, 530 participants; P = 0.19, I2 = 4%; low-certainty evidence). Despite sensitivity analysis, the direction of the evidence remained unchanged. No trials measured cardiovascular mortality. There may be little to no difference in the length of hospital stay between continuous infusion and bolus injection of loop diuretics, but the evidence is very uncertain (MD -1.10 days, 95% CI -4.84 to 2.64; 4 trials, 211 participants; P = 0.57, I2 = 88%; very low-certainty evidence). Sensitivity analysis improved heterogeneity; however, the direction of the evidence remained unchanged. There may be little to no difference in the readmission to hospital between continuous infusion and bolus injection of loop diuretics (RR 0.85, 95% CI 0.63 to 1.16; 3 trials, 400 participants; P = 0.31, I2 = 0%; low-certainty evidence). Sensitivity analysis continued to show insufficient evidence for a difference in the readmission to hospital between groups. There may be little to no difference in the occurrence of acute kidney injury as an adverse event between continuous infusion and bolus injection of intravenous loop diuretics (RR 1.02, 95% CI 0.70 to 1.49; 3 trials, 491 participants; P = 0.92, I2 = 0%; low-certainty evidence). Sensitivity analysis continued to show that continuous infusion may make little to no difference on the occurrence of acute kidney injury as an adverse events compared to the bolus injection of intravenous loop diuretics. AUTHORS' CONCLUSIONS: Analysis of available data comparing two delivery methods of diuretics in acute heart failure found that the current data are insufficient to show superiority of one strategy intervention over the other. Our findings were based on trials meeting stringent inclusion and exclusion criteria to ensure validity. Despite previous reviews suggesting advantages of continuous infusion over bolus injections, our review found insufficient evidence to support or refute this. However, our review, which excluded trials with clinical confounders and RCTs with high risk of bias, offers the most robust conclusion to date.

Loop diuretic down-titration at discharge in patients hospitalized for acute heart failure.

AIMS: The current literature provides limited guidance on the best diuretic strategy post-hospitalization for acute heart failure (AHF). It is postulated that the efficacy and safety of the outpatient diuretic regimen may be significantly influenced by the degree of fluid overload (FO) encountered during hospitalization. We hypothesize that in patients with more pronounced FO, reducing their regular oral diuretic dosage might be associated with an elevated risk of unfavourable clinical outcomes. METHODS AND RESULTS: It was a retrospective observational study of 410 patients hospitalized for AHF in which the dose of furosemide at admission and discharge was collected. Patients were categorized across diuretic dose status into two groups: (i) the down-titration group and (ii) the stable/up-titration group. FO status was evaluated by a clinical congestion score and circulating biomarkers. The endpoint of interest was the composite of time to all-cause death and/or heart failure readmission. A multivariable Cox proportional hazard regression model was constructed to analyse the endpoints. The median age was 86 (78-92) years, 256 (62%) were women, and 80% had heart failure with preserved ejection fraction. After multivariate adjustment, the down-titration furosemide equivalent dose remained not associated with the risk of the combined endpoint in the whole sample (hazard ratio 1.34, 95% confidence interval 0.86-2.06, P = 0.184). The risk of the combination of death and/or worsening heart failure associated with the diuretic strategy at discharge was significantly influenced by FO status, including clinical congestion scores and circulating proxies of FO like BNP and cancer antigen 125. CONCLUSIONS: In patients hospitalized for AHF, furosemide down-titration does not imply an increased risk of mortality and/or heart failure readmission. However, FO status modifies the effect of down-titration on the outcome. In patients with severe congestion or residual congestion at discharge, down-titration was associated with an increased risk of mortality and/or heart failure readmission.

Diuretic use and outcomes in patients with heart failure with reduced ejection fraction: Insights from the VICTORIA trial.

AIMS: In VICTORIA, vericiguat compared with placebo reduced the risk of cardiovascular death (CVD) and heart failure hospitalization (HFH) in patients enrolled after a worsening heart failure (WHF) event. We examined clinical outcomes and efficacy of vericiguat as it relates to background use of loop diuretics in patients with WHF. METHODS AND RESULTS: We calculated the total daily loop diuretic dose equivalent to furosemide dosing at randomization and categorized these as: no loop diuretic, 1-39, 41-80, 40, and >80 mg total daily dose (TDD). The primary composite outcome of CVD/HFH and its components were evaluated based on TDD loop diuretic and expressed as adjusted hazard ratios with 95% confidence intervals. Post-randomization rates of change in TDD were also examined. Of 4974 patients (98% of the trial) with diuretic dose information available at randomization, 540 (10.8%) were on no loop diuretic, 647 (13.0%) were on 1-39, 1633 (32.8%) were on 40, 1185 (23.8%) were on 41-80, and 969 (19.4%) were on >80 mg TDD. Patients with higher TDD had a higher rate of primary and secondary clinical outcomes. There were no significant interactions with TDD at randomization and efficacy of vericiguat versus placebo for any outcome (all pinteraction > 0.5). Post-randomization diuretic dose changes for vericiguat and placebo showed similar rates of up-titration (19.6 and 20.2/100 person-years), down-titration (16.8 and 18.1/100 person-years), and stopping diuretics (22.9 and 24.2/100 person-years). CONCLUSIONS: Loop diuretic TDD at randomization was independently associated with worse outcomes in this high-risk population. The efficacy of vericiguat was consistent across the range of diuretic doses.

Effect of pregabalin initiation on diuretic requirements in patients with chronic heart failure.

BACKGROUND: Literature on pregabalin use in patients with heart failure is largely limited to patient case reports and cohort studies. OBJECTIVE: This study aimed to evaluate the effect of pregabalin initiation on diuretic requirements in patients with heart failure. METHODS: A retrospective analysis of patients with heart failure who were started on pregabalin between January 1, 2014, and September 1, 2021, at the Veterans Affairs North Texas Health Care System was used. The primary objective was to determine the median change in loop diuretic dose, in furosemide dose equivalents, 6 months after pregabalin initiation. RESULTS: Of 58 patients analyzed, there was no statistically significant difference in the primary outcome (P = 0.162). The secondary outcomes were found to be nonstatistically significant, and there was no correlation between pregabalin dose and outcomes. CONCLUSION: This represents the largest analysis of diuretic dose requirements in patients with heart failure after initiation of pregabalin. Although there was no difference in the median change of diuretic dose prescribed, pregabalin should still be used with caution.

Suitable Dose of Long-Term Tolvaptan to Reduce Heart Failure Rehospitalizations.

The short-term effectiveness of tolvaptan (TLV) for heart failure (HF) has been established, but the long-term effects are controversial. We investigated HF patients who could not discontinue both loop diuretics and TLV at discharge from AURORA (Acute Heart Failure Registry in Osaka Rosai Hospital). We compared the following factors at discharge between the RH group, consisting of patients with rehospitalizations due to worsening HF within 1 year after discharge (RH group), and non-RH group: age, gender, blood pressure, history of HF admission, electrocardiogram and echocardiographic parameters, atherosclerotic risk factors, laboratory data, and medications. Furthermore, we compared the effects of long-term low-dose TLV (≤ 7.5 mg/day) and high-dose TLV on HF rehospitalizations. The RH group consisted of 81 patients (58.7%). A multivariate analysis revealed that a history of HF admission and the TLV dose were independently and significantly associated with 1-year HF rehospitalizations. A receiver operating characteristic curve revealed that 7.5 mg of TLV was a suitable cutoff value for 1-year HF rehospitalizations. The Kaplan-Meier curves demonstrated that the HF rehospitalization free ratio was significantly higher in the low-dose TLV group (≤ 7.5 mg/day) than in high-dose TLV group over 1 year.In conclusion, the TLV dose, in addition to a history of HF admission, was associated with 1-year HF rehospitalizations in diuretic-dependent HF patients. In these patients, long-term low-dose TLV (≤ 7.5 mg/day) may be favorable for reducing HF rehospitalizations.

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.

Pathology-selective antiepileptic effects in the focal freeze-lesion rat model of malformation of cortical development.

Malformations of cortical development (MCD) represent a group of rare diseases with severe clinical presentation as epileptic and pharmacoresistant encephalopathies. Morphological studies in tissue from MCD patients have revealed reduced GABAergic efficacy and increased intracellular chloride concentration in neuronal cells as important pathophysiological mechanisms in MCD. Also, in various animal models, alterations of GABAergic inhibition have been postulated as a predominant factor contributing to perilesional hyperexcitability. Along with this line, the NKCC1 inhibitor bumetanide has been postulated as a potential drug for treatment of epilepsy, mediating its antiepileptic effect by reduction of the intracellular chloride and increased inhibitory efficacy of GABAergic transmission. In the present study, we focused on the focal freeze-lesion model of MCD to compare antiepileptic drugs with distinct mechanisms of action, including NKCC1 inhibition by bumetanide. For this purpose, we combined electrophysiological and optical methods in slice preparations and assessed the properties of seizure like events (SLE) induced by 4-aminopyridine. In freeze-lesioned but not control slices, SLE onset was confined to the perilesional area, confirming that this region is hyperexcitable and likely triggers pathological activity. Bumetanide selectively reduced epileptic activity in lesion-containing slices but not in slices from sham-treated control rats. Moreover, bumetanide caused a shift in the SLE onset site away from the perilesional area. In contrast, effects of other antiepileptic drugs including carbamazepine, lacosamide, acezatolamide and zonisamide occurred mostly independently of the lesion and did not result in a shift of the onset region. Our work adds evidence for the functional relevance of chloride homeostasis in the pathophysiology of microgyrus formation as represented in the focal freeze-lesion model. Further studies in different MCD models and human tissue will be required to validate the effects across different MCD subtypes and species and to assess the translational value of our findings.

Efficacy and safety of intermittent vs continuous furosemide for heart failure concomitant renal dysfunction: A protocol for systematic review and meta-analysis.

BACKGROUND: Currently, there are no meta-analyses evaluating the efficacy and safety of intermittent vs continuous furosemide for heart failure concomitant renal dysfunction. Our protocol is conceived to evaluate the efficacy and safety of intermittent vs continuous furosemide for heart failure concomitant renal dysfunction. METHODS: We will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines and the recommendations of the Cochrane Collaboration to conduct this meta-analysis. The systematic review protocol has been registered in Open Science Framework registries. The following databases including PubMed, Cochrane Library, Web of Science, and EMBASE will be searched using the key phrases "loop diuretics," "furosemide," "heart failure," and "renal dysfunction" for all randomized clinical trials (RCTs) published up to May 2021. Revman 5.3 (Nordic Cochrane Centre, Denmark) will be used to complete the meta-analysis and generate forest plots. We will choose between a fixed effects and random effects model based upon the heterogeneity of included studies. Significance will be set at P < .05. RESULTS: Our protocol is conceived to test the hypothesis that continuous furosemide could lead to better outcomes in patients presenting with heart failure concomitant renal dysfunction. REGISTRATION NUMBER: 10.17605/OSF.IO/CQZRS.

Effects of the NKCC1 inhibitors bumetanide, azosemide, and torasemide alone or in combination with phenobarbital on seizure threshold in epileptic and nonepileptic mice.

The sodium-potassium-chloride (Na-K-Cl) cotransporter NKCC1 is found in the plasma membrane of a wide variety of cell types, including neurons, glia and endothelial cells in the brain. Increased expression of neuronal NKCC1 has been implicated in several brain disorders, including neonatal seizures and epilepsy. The loop diuretic and NKCC inhibitor bumetanide has been evaluated as an antiseizure agent alone or together with approved antiseizure drugs such as phenobarbital (PB) in pre-clinical and clinical studies with varying results. The equivocal efficacy of bumetanide may be a result of its poor brain penetration. We recently reported that the loop diuretic azosemide is more potent to inhibit NKCC1 than bumetanide. In contrast to bumetanide, azosemide is not acidic, which should favor its brain penetration. Thus, azosemide may be a promising alternative to bumetanide for treatment of brain disorders such as epilepsy. In the present study, we determined the effect of azosemide and bumetanide on seizure threshold in adult epileptic mice. A structurally related non-acidic loop diuretic, torasemide, which also blocks NKCC1, was included in the experiments. The drug effects were assessed by determing the maximal electroshock seizure threshold (MEST) in epileptic vs. nonepileptic mice. Epilepsy was induced by pilocarpine, which was shown to produce long-lasting increases in NKCC1 in the hippocampus, whereas MEST did not alter NKCC1 mRNA in this region. None of the three loop diuretics increased MEST or the effect of PB on MEST in nonepileptic mice. In epileptic mice, all three diuretics significantly increased PB's seizure threshold increasing efficacy, but the effect was variable upon repeated MEST determinations and not correlated with the drugs' diuretic potency. These data may indicate that inhibition of NKCC1 by loop diuretics is not an effective means of increasing seizure threshold in adult epilepsy.

Intensification of pharmacological decongestion but not the actual daily loop diuretic dose predicts worse chronic heart failure outcome: insights from TIME-CHF.

BACKGROUND: Both loop diuretics (LDs) and congestion have been related to worse heart failure (HF) outcome. The relationship between the cause and effect is unknown. The aim of this study was to investigate the interaction between congestion, diuretic use and HF outcome. METHODS: Six hundred and twenty-two chronic HF patients from TIME-CHF were studied. Congestion was measured by means of a clinical congestion index (CCI). Loop diuretic dose was considered at baseline and month 6. Treatment intensification was defined as the increase in LD dose over 6 months or loop diuretic and thiazide or thiazide-like diuretic co-administration. The end-points were survival and HF hospitalisation-free survival. RESULTS: High-LD dose at baseline and month 6 (≥ 80 mg of furosemide per day) was not identified as an independent predictor of outcome. CCI at baseline remained independently associated with impaired survival [hazard ratio (HR) 1.34, (95% confidence interval) (95% CI) (1.20-1.50), p < 0.001] and HF hospitalisation-free survival [HR 1.09, 95% CI (1.02-1.17), p = 0.015]. CCI at month 6 was independently associated with HF hospitalisation-free survival [HR 1.24, 95% CI (1.11-1.38), p < 0.001]. Treatment intensification was independently associated with survival [HR 1.75, 95% CI (1.19-1.38), p = 0.004] and HF hospitalisation-free survival [HR 1.69, 95% CI (1.22-2.35), p = 0.002]. Patients undergoing treatment intensification resulting in decongestion had better outcome than patients with persistent (worsening) congestion despite LD dose up-titration (p < 0.001). CONCLUSION: Intensification of pharmacological decongestion but not the actual LD dose was related to poor outcome in chronic HF. If treatment intensification translated into clinical decongestion, outcome was better than in case of persistent or worsening congestion.

Rationale and Design of the Genotype-Blinded Trial of Torasemide for the Treatment of Hypertension (BHF UMOD).

BACKGROUND: Genome-wide association studies have identified single nucleotide polymorphisms (SNPs) near the uromodulin gene (UMOD) affecting uromodulin excretion and blood pressure (BP). Uromodulin is almost exclusively expressed in the thick ascending limb (TAL) of the loop of Henle and its effect on BP appears to be mediated via the TAL sodium transporter, NKCC2. Loop-diuretics block NKCC2 but are not commonly used in hypertension management. Volume overload is one of the primary drivers for uncontrolled hypertension, so targeting loop-diuretics to individuals who are more likely to respond to this drug class, using the UMOD genotype, could be an efficient precision medicine strategy. METHODS: The BHF UMOD Trial is a genotype-blinded, multicenter trial comparing BP response to torasemide between individuals possessing the AA genotype of the SNP rs13333226 and those possessing the G allele. 240 participants (≥18 years) with uncontrolled BP, on ≥1 antihypertensive agent for ≥3 months, will receive treatment with Torasemide, 5 mg daily for 16 weeks. Uncontrolled BP is average home systolic BP (SBP) >135 mmHg and/or diastolic BP >85 mmHg. The primary outcome is the change in 24-hour ambulatory SBP area under the curve between baseline and end of treatment. Sample size was calculated to detect a 4 mmHg difference between groups at 90% power. Approval by West of Scotland Research Ethics Committee 5 (16/WS/0160). RESULTS: The study should conclude August 2021. CONCLUSIONS: If our hypothesis is confirmed, a genotype-based treatment strategy for loop diuretics would help reduce the burden of uncontrolled hypertension. CLINICAL TRIALS REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT03354897.

Renal and Cardiovascular Effects of SGLT2 Inhibition in Combination With Loop Diuretics in Patients With Type 2 Diabetes and Chronic Heart Failure: The RECEDE-CHF Trial.

BACKGROUND: SGLT2 (sodium-glucose cotransporter-2) inhibitors improve heart failure-associated outcomes in patients with type 2 diabetes. In patients with heart failure, SGLT2 inhibitors will likely be coprescribed with a loop diuretic, but this combined effect is not well-defined. Our aim was to assess the diuretic and natriuretic effect of empagliflozin in combination with loop diuretics. METHODS: The RECEDE-CHF trial (SGLT2 Inhibition in Combination With Diuretics in Heart Failure) was a randomized, double-blind, placebo-controlled, crossover trial of patients with type 2 diabetes and heart failure with reduced ejection fraction taking regular loop diuretic who were randomized to empagliflozin 25 mg once daily or placebo for 6 weeks with a 2-week washout period. The primary outcome was change in 24-hour urinary volume from baseline to week 6. RESULTS: Twenty-three participants (mean age, 69.8 years; 73.9% male; mean furosemide dose, 49.6±31.3 mg/d; mean HbA1c, 7.9±3.8%) were recruited. Compared with placebo, empagliflozin caused a significant increase in 24-hour urinary volume at both day 3 (mean difference, 535 mL [95% CI, 133-936]; P=0.005) and week 6 (mean difference, 545 mL [95% CI, 136-954]; P=0.005) after adjustment for treatment order, baseline 24-hour urine volume, and percentage change in loop diuretic dose. At 6 weeks, empagliflozin did not cause a significant change in 24-hour urinary sodium (mean difference, -7.85 mmol/L [95% CI, -2.43 to 6.73]; P=0.57). Empagliflozin caused a nonsignificant increase in fractional excretion of sodium at day 3, which was absent at week 6 (mean difference day 3, 0.30% [95% CI, -0.03 to 0.63]; P=0.09; week 6, 0.11% [95% CI, -0.22 to 0.44]; P>0.99), and a significant increase in electrolyte-free water clearance at week 6 (mean difference, 312 mL [95% CI, 26-598]; P=0.026) compared with placebo. Empagliflozin also caused significant reductions in body weight and serum urate at week 6. CONCLUSIONS: Empagliflozin caused a significant increase in 24-hour urine volume without an increase in urinary sodium when used in combination with loop diuretic. Registration: URL: https://www.clinicaltrials.gov; Unique Identifier: NCT03226457.

Patients with acute heart failure treated with the CARRESS-HF diuretic protocol in association with canrenoate potassium: Tolerance of high doses of canrenoate potassium.

BACKGROUND: Oral mineralocorticoid receptor antagonists have failed to prove their efficacy for decongestion and potassium homeostasis in acute heart failure. Intravenous mineralocorticoid receptor antagonists have yet to be studied. AIM: The aim of this study was to confirm the safety of high-dose potassium canrenoate in association with classic diuretics in acute heart failure. METHODS: This retrospective single-centre study included consecutive patients who were hospitalized with acute heart failure between 2013 and 2018. One hundred patients with overload treated with the standardized diuretic protocol from the CARRESS-HF trial were included. There were no exclusion criteria relating to creatinine or kalaemia at the time of admission. Two groups were constituted on the basis of potassium canrenoate posology: a low-dose group (<300mg/day) and a high-dose group (≥300mg/day); the groups were similar in terms of baseline characteristics. RESULTS: Mean daily potassium canrenoate doses were 198mg/day (range 100-280mg/day) in the low-dose group and 360mg/day (range 300-600mg/day) in the high-dose group. There was no significant difference between the high-dose and low-dose groups in terms of mortality, dialysis, renal function, hyperkalaemia, haemorrhage, sepsis or confusion. CONCLUSIONS: Potassium canrenoate at high doses can be used safely in association with standard diuretics in acute heart failure, even in patients with altered renal function. A prospective study is required to evaluate the efficacy of high-dose potassium canrenoate in preventing hypokalaemia and improving decongestion.

Treatment outcomes of bumetanide continuous infusion: A systematic review and meta-analysis.

The clinical use of continuous bumetanide infusion for acute heart failure and volume overload is common. However, there is not enough supporting evidence for the use of continuous bumetanide infusion. Thus, we conducted this systematic review and meta-analysis aiming to describe the treatment outcomes of continuous bumetanide infusion. We searched Ovid MEDLINE, EMBASE and the Cochrane Library for eligible publications. Inclusion criteria were patients age ≥18 years with bumetanide infusion for heart failure, acute kidney injury (AKI) or volume overload. From 1564 citations, three studies (n = 94 patients) were included in the systematic review and meta-analysis. The mean dose of bumetanide was 1.08 ± 0.43 mg/hour with a mean treatment duration of 45.09 ± 10.12 hours. Mean urine output in response to continuous bumetanide infusion was 1.88 mL/kg/hour (95% confidence interval [CI], 1.72-2.05). The incidence of AKI with continuous bumetanide infusion was 24.7% (95% CI, 8.2-54.6). By using Pearson's correlation coefficient, increasing doses of bumetanide were correlated with increased urine output (P = .026) and increased incidence of AKI (P < .01). There was no correlation between increasing urine output and the incidence of AKI (P = .739). In conclusion, with available evidence, continuous bumetanide infusion may be used in the treatment of acute heart failure or volume overload with close monitoring for new-onset or worsening AKI.

The Impact of Discharged Loop Diuretic Dose to Home Dose on Hospital Readmissions in Patients with Acute Decompensated Heart Failure: A Retrospective Cohort Study.

BACKGROUND: Acute decompensated heart failure (ADHF) is associated with a high rate of hospital readmission. The aim of this study is to examine the effect of the discharge diuretic dose compared with the home diuretic dose on hospital readmission in patients with ADHF. METHODS: A single center retrospective cohort study included patients with a confirmed diagnosis of ADHF with an ejection fraction of less than 40%. The sample was divided in two groups. The first group received a total daily discharge diuretic dose that was greater than the home dose; the second group received a daily discharge diuretic that was equal to or less than the home dose. The primary outcome was all-cause 30-day readmission rate. The secondary outcomes were all-cause 60-day and 90-day readmission rates. RESULTS: A total of 206 patients met inclusion criteria; 117 patients received a higher loop diuretic dose at discharge, while 89 were discharged with a loop diuretic that was equal to or less than the home dose. Patients in the increased-dose group had an all-cause 30-day readmission rate of 20.5% compared with 37.1% of patients with equal or reduced-dose group; P = .007. Additionally, there were lower readmission rates in 60 and 90 days between the increased and equal or reduced groups (33.3% versus 52.8%, P < .017, and 41.0% versus 62.9%, P < .003, respectively. CONCLUSIONS: Among patients admitted to hospital with ADHF and reduced ejection fraction, a discharge loop diuretic dose higher than the home dose was associated with decreased all-cause 30-day, 60-day, and 90-day readmission rates.

Is Inhaled Furosemide a Potential Therapeutic for COVID-19?

The potentially lethal infection caused by the novel Severe Acute Respiratory Disease Coronavirus-2 (SARS-CoV-2) has evolved into a global crisis. Following the initial viral infection is the host inflammatory response that frequently results in excessive secretion of inflammatory cytokines (e.g., IL-6 and TNFα), developing into a self-targeting, toxic "cytokine storm" causing critical pulmonary tissue damage. The need for a therapeutic that is available immediately is growing daily but the de novo development of a vaccine may take years. Therefore, repurposing of approved drugs offers a promising approach to address this urgent need. Inhaled furosemide, a small molecule capable of inhibiting IL-6 and TNFα, may be an agent capable of treating the Coronavirus Disease 2019 cytokine storm in both resource-rich and developing countries. Furosemide is a "repurpose-able" small molecule therapeutics, that is safe, easily synthesized, handled, and stored, and is available in reasonable quantities worldwide.

Electrolyte Abnormalities in Patients Presenting With Ventricular Arrhythmia (from the LYTE-VT Study).

Electrolyte abnormalities are a known trigger for ventricular arrhythmia, and patients with heart disease on diuretic therapy may be at higher risk for electrolyte depletion. Our aim was to determine the prevalence of electrolyte depletion in patients presenting to the hospital with sustained ventricular tachycardia or ventricular fibrillation (VT/VF) versus heart failure, and identify risk factors for electrolyte depletion. Consecutive admissions to a tertiary care hospital for VT/VF were identified between July 2016 and October 2018 using the electronic medical record and compared with an equal number of consecutive admissions for heart failure (CHF). The study included 280 patients (140 patients in each group; mean age 63, 60% male, 59% African American). Average EF in the VT/VF and CHF groups was 30% and 33%, respectively. Hypokalemia (K < 3.5 mmol/L) and severe hypokalemia (K < 3.0 mmol/L) were present in 35.7% and 13.6%, respectively, of patients with VT/VF, compared to 12.9% and 2.7% of patients with CHF (p < 0.001 and p = 0.001, respectively, between groups). Hypomagnesemia was found in 7.8% and 5.8% of VT/VF and CHF patients, respectively (p = 0.46). Gastrointestinal illness and recent increases in diuretic dose were strongly associated with severe hypokalemia in VT/VF patients (odds ratio: 11.1 and 21.9, respectively; p < 0.001). In conclusion, hypokalemia is extremely common in patients presenting with VT/VF, much more so than in patients with CHF alone. Preceding gastrointestinal illness and increase in diuretic dose were strongly associated with severe hypokalemia in the VT/VF population, revealing a potential opportunity for early intervention and arrhythmia risk reduction.

Contribution of Monocarboxylate Transporter 6 to the Pharmacokinetics and Pharmacodynamics of Bumetanide in Mice.

Bumetanide, a sulfamyl loop diuretic, is used for the treatment of edema in association with congestive heart failure. Being a polar, anionic compound at physiologic pH, bumetanide uptake and efflux into different tissues is largely transporter-mediated. Of note, organic anion transporters (SLC22A) have been extensively studied in terms of their importance in transporting bumetanide to its primary site of action in the kidney. The contribution of one of the less-studied bumetanide transporters, monocarboxylate transporter 6 (MCT6; SLC16A5), to bumetanide pharmacokinetics (PK) and pharmacodynamics (PD) has yet to be characterized. The affinity of bumetanide for murine Mct6 was evaluated using Mct6-transfected Xenopus laevis oocytes. Furthermore, bumetanide was intravenously and orally administered to wild-type mice (Mct6+/+) and homozygous Mct6 knockout mice (Mct6-/-) to elucidate the contribution of Mct6 to bumetanide PK/PD in vivo. We demonstrated that murine Mct6 transports bumetanide at a similar affinity compared with human MCT6 (78 and 84 µM, respectively, at pH 7.4). After bumetanide administration, there were no significant differences in plasma PK. Additionally, diuresis was significantly decreased by ∼55% after intravenous bumetanide administration in Mct6-/- mice. Kidney cortex concentrations of bumetanide were decreased, suggesting decreased Mct6-mediated bumetanide transport to its site of action in the kidney. Overall, these results suggest that Mct6 does not play a major role in the plasma PK of bumetanide in mice; however, it significantly contributes to bumetanide's pharmacodynamics due to changes in kidney concentrations. SIGNIFICANCE STATEMENT: Previous evidence suggested that MCT6 transports bumetanide in vitro; however, no studies to date have evaluated the in vivo contribution of this transporter. In vitro studies indicated that mouse and human MCT6 transport bumetanide with similar affinities. Using Mct6 knockout mice, we demonstrated that murine Mct6 does not play a major role in the plasma pharmacokinetics of bumetanide; however, the pharmacodynamic effect of diuresis was attenuated in the knockout mice, likely because of the decreased bumetanide concentrations in the kidney.