A perspective on diuretic resistance in chronic congestive heart failure

Diuretic resistance and the role of albumin in congestive heart failure

Diuresis with loop diuretics is the mainstay treatment for volume optimization in patients with congestive heart failure, in which perfusion and volume expansion play a crucial role. There are robust guidelines with extensive evidence for the management of heart failure; however, clear guidance is needed for patients who do not respond to standard diuretic treatment. Diuretic resistance (DR) can be defined as an insufficient quantity of natriuresis with proper diuretic therapy. A combination of diuretic regimens is used to overcome DR and, more recently, SGLT2 inhibitors have been shown to improve diuresis. Despite DR being relatively common, it is challenging to treat and there remains a notable lack of substantial data guiding its management. Moreover, DR has been linked with poor prognosis. This review aims to expose the multiple approaches for treatment of patients with DR and the importance of intravascular volume expansion in the response to therapy.

Natriuretic Peptide Receptors (NPRs) as a Potential Target for the Treatment of Heart Failure

PURPOSE OF REVIEW

Heart failure is defined as a complex clinical syndrome that results from any structural or functional impairment of ventricular filling or ejection of blood. The natriuretic peptide is known to exert its biological action on the kidney, heart, blood vessels, renin-angiotensin system, autonomous nervous system, and central nervous system. The natriuretic peptide-natriuretic receptor system plays an important role in the regulation of blood pressure and body fluid volume through its pleiotropic effects.

RECENT FINDINGS

The clinical and animal studies suggest that natriuretic peptide-natriuretic receptors are important targets for the treatment of heart failure and other cardiovascular diseases. Even though attempts targeting natriuretic peptide receptors are underway for heart failure treatment, they seem insufficient despite the receptor systems' potential. This review summarizes natriuretic peptide-natriuretic receptor system's physiological actions and potential target for the treatment of heart failure. Natriuretic peptides play multiple roles in different parts of the body, almost all of the activities related to this receptor system appear to have the potential to be harnessed to treat heart failure or symptoms associated with heart failure.

Diuretic-resistant heart failure and the role of ultrafiltration: A proposed protocol

Acute heart failure (HF) decompensation generally manifests with signs and symptoms of congestion that strongly predict poor poor patient outcome. Loop diuretics are the cornerstone of therapy to counteract fluid overload and are widely used for acute management and chronic stabilization of HF. However, a diminished response to loop diuretics is a common problem, affecting the patient's clinical course and potentially prolonging hospitalization. Diuretic resistance is defined as failure to decongest despite appropriate and escalating loop diuretic therapy. We propose a protocol for the management of diuretic resistance. The initial approach should include an assessment of causes of pseudo-diuretic resistance. Adjustments to loop diuretic therapy, such as increasing doses and frequency of administration and sequential nephron blockade, may be successful. For hospitalized patients with progressive disease there are more invasive methods for fluid removal. Switching from oral to intravenous loop diuretics is essential to avoid variable absorption and for symptomatic relief. Extracorporeal ultrafiltration is also an option since this technique is highly effective at removing plasma fluid from blood. While extracorporeal ultrafiltration is an invasive solution, peritoneal dialysis is a home-based, intermittent therapeutic option that can enable efficient management of fluid overload, preventing HF-related hospital admission, and improving quality of life. As a last resort for fluid removal, a peritoneal dialysis regimen should fully exploit its decongestive properties and should be tailored to the patient's characteristics and clinical needs.

Toward quantification of loop diuretic responsiveness for congestive heart failure

Diuretics, such as furosemide, are routinely administered to dogs with congestive heart failure (CHF). Traditionally, dose and determination of efficacy primarily are based on clinical signs rather than quantitative measures of drug action. Treatment of human CHF patients increasingly is guided by quantification of urine sodium concentration (uNa) and urine volume after diuretic administration. Use of these and other measures of diuretic responsiveness is associated with decreased duration of hospitalization, complication rates, future rehospitalization, and mortality. At their core, loop diuretics act through natriuresis, and attention to body sodium (Na) stores and handling offers insight into the pathophysiology of CHF and pharmacology of diuretics beyond what is achievable from clinical signs alone. Human patients with low diuretic responsiveness or diuretic resistance are at risk for difficult or incomplete decongestion that requires diuretic intensification or other remedial strategies. Identification of the specific etiology of resistance in a patient can help tailor personalized interventions. In this review, we advance the concept of loop diuretic responsiveness by highlighting Na and natriuresis. Specifically, we review body water homeostasis and congestion in light of the increasingly recognized role of interstitial Na, propose definitions for diuretic responsiveness and resistance in veterinary subjects, review relevant findings of recent studies, explain how the particular cause of resistance can guide treatment, and identify current knowledge gaps. We believe that a quantitative approach to loop diuretic usage primarily involving natriuresis will advance our understanding and care of dogs with CHF.

Comprehensive and Safe Decongestion in Acutely Decompensated Heart Failure

PURPOSE OF THE REVIEW

Progressive intravascular, interstitial, and alveolar fluid overload underlies the transition from compensated to acutely decompensated heart failure and loop diuretics are the mainstay of treatment. Adverse effects and resistance to loop diuretics received much attention while the contribution of a depressed cardiac output to diuretic resistance was downplayed.

RECENT FINDINGS

Analysis of experience with positive inotropic agents, especially dobutamine, indicates that enhancement of cardiac output is not consistently associated with increased renal blood flow. However, urinary output and renal sodium excretion increase likely due to dobutamine-mediated decrease in renal and systemic reduced activation of sympathetic nervous- and renin-angiotensin-aldosterone system. Mechanical circulatory support with left ventricular assist devices ascertained the contribution of low cardiac output to diuretic resistance and the pathogenesis and progression of kidney disease in acutely decompensated heart failure. Diuretic resistance commonly occurs in acutely decompensated heart failure. However, failure to resolve fluid overload despite high doses of loop diuretics should alert to the presence of a low cardiac output state.

From Oral to Subcutaneous Furosemide: The Road to Novel Opportunities to Manage Congestion

The steadily rising prevalence of heart failure (HF) and the associated increase in health care expenditures represent a significant burden for patients, caregivers, and society. Ambulatory management of worsening congestion is a complex undertaking that requires diuretic escalation, yet clinical success is often hindered by the progressively declining bioavailability of oral agents. Once beyond a threshold, patients with acute on chronic HF often require hospital admission for intravenous diuresis. A novel, pH neutral formulation of furosemide that is administered by a biphasic drug delivery profile (80 mg total over 5 ​hours) via an automated, on-body infusor was designed to overcome these limitations. Early studies have shown that it has equivalent bioavailability with comparable diuresis and natriuresis to the intravenous formulation, leads to significant decongestion, and improvement in quality of life. It was shown to be safe and is well tolerated by patients. Although there is one ongoing clinical trial, available data have demonstrated the potential to shift hospital-administered, intravenous diuresis to the outpatient setting. Reduction in the need for recurrent hospital admissions would be highly desirable by most patients with chronic HF and would lead to a significant reduction in health care expenditures. In this article, we describe the rationale and evolution of this novel PH neutral formulation of furosemide administered subcutaneously, summarize its pharmacokinetic and pharmacodynamic profiles, and review emerging clinical trials demonstrating its clinical safety, efficacy, and potential to reduce health care expenditures.

Effectiveness and cost-efficacy of diuretics home administration via peripherally inserted central venous catheter in patients with end-stage heart failure

BACKGROUND

End-stage heart failure (ESHF) is characterized by severe cardiac dysfunction with persistent disabling symptoms and recurrent acute decompensated heart failure (ADHF), despite guideline-directed medical therapy. The aim of this study was to evaluate the efficacy and safety of intravenous diuretics administration at home through a peripherally inserted central venous catheter (PICC) in ESHF patients.

METHODS AND RESULTS

Forty-one ESHF patients received PICC implantation for intravenous diuretic administration at home. The primary efficacy endpoint was the patient-level number of HF hospitalizations in the short (1-3 months), medium (six months), and long term (1 year), before and after PICC implantation. Pre- and post-PICC ADHF-free days were also evaluated as co-primary endpoint. Secondary endpoints comprised changes in clinical, laboratory and echocardiographic parameters, and device safety. A cost-effectiveness analysis was performed to estimate the economic impact of using PICC. For each time frame analyzed, a significant reduction in the number of hospitalizations due to ADHF was observed, resulting in a significant increase in ADHF-free days (71 ± 44 vs. 163 ± 136, p = 0.003). In matched patients' analysis, significant decrease in body weight (68 ± 16 kg vs. 63 ± 10 kg, p = 0.041) and mitral regurgitation grade 3/4 (55% vs. 18%, p < 0.001) were also observed. Freedom from PICC-related complications was observed in 61% of patients. A significant reduction in overall ADHF-hospitalizations cost was observed.

CONCLUSIONS

This proof-of-concept study demonstrates the effectiveness and safety of home administration of intravenous diuretic therapy via PICC in ESHF patients. This palliative cost-effective strategy can be taken in consideration for selected end-stage patients no longer responsive to conventional therapies.

Diuretic therapy in congestive heart failure

In heart failure, fluid overload is a major pathological mechanism leading to vascular congestion, pulmonary congestion and elevated jugular venous pressures. Diuretics play a significant role in the management of patients with congestive heart failure. It is used to relieve the congestive symptoms of heart failure. However, the appropriate use of diuretics remains challenging due to various complications like electrolyte abnormalities, worsening renal function and diuretic resistance. This has prompted towards the search of safer and effective alternatives. This review evaluates the use of diuretics in congestive heart failure and discusses the complications of different types of diuretics, which is essential for successful management of congestion in patients with heart failure and hence to optimise the outcome for the patients.

Impact of Outpatient Diuretic Infusion Therapy on Healthcare Cost and Readmissions

Background and Objectives

Heart failure (HF) is a complex syndrome with multiple etiologies resulting in impaired ventricular filling or pumping of blood. HF is as a major public health concern that leads to significant morbidity and mortality resulting in an enormous financial burden on the healthcare system. The study objectives were to assess the 30-day hospital readmission rates and its financial impact on the hospital.

Methods

The study was a retrospective single-center analysis of decoded data of all HF patients admitted to an outpatient diuretic infusion program. Adult patients who were readmitted to the hospital within 30 days despite guideline derive medical therapy were included if they were enrolled in the outpatient diuretic infusion clinic. Adult patients who were included in this study received a furosemide dose of 40 mg intravenously (infusion over 3 hours) at the clinic visit. Patients whose clinical signs/symptoms improved and remained stable in consequent visits were eventually discharged from the clinic. Financial impact was assessed using data obtained from the hospital administration on cost of HF readmissions.

Results

The results show a 30-day hospital readmission rate at 6–9% in the years analyzed (n=56) with a net savings of $562,815 to $736,560 per year.

Conclusions

This treatment strategy has no detrimental effects in addition to generating substantial financial savings. It appears to be a useful addition to the existing medical treatment regimens chronic HF patients.

[Hypertonic saline solution and high dose of diuretic, ¿what do we know and how can we use them in persistent congestion?]

The presence of decompensated heart failure continues to be a condition with high rates of hospitalization, impact on the health system, and quality of life for those who suffer it. The mainstay of treatment in these cases are diuretics. However, the resistance to this pharmacological group may occasionally occur, generating an inadequate negative fluid balance and persistence of congestion with negative clinical outcomes. Hypertonic saline solution with high doses of diuretic emerges as a therapeutic option for this group of patients with probable physiological, and clinical benefits on hospitalization and re-admission rates due to heart failure decompensation. A review of the most relevant aspects and benefits of this combination is discussed in this article.

Improving Diuretic Response in Heart Failure by Implementing a Patient-Tailored Variability and Chronotherapy-Guided Algorithm

Heart failure is a major public health problem, which is associated with significant mortality, morbidity, and healthcare expenditures. A substantial amount of the morbidity is attributed to volume overload, for which loop diuretics are a mandatory treatment. However, the variability in response to diuretics and development of diuretic resistance adversely affect the clinical outcomes. Morevoer, there exists a marked intra- and inter-patient variability in response to diuretics that affects the clinical course and related adverse outcomes. In the present article, we review the mechanisms underlying the development of diuretic resistance. The role of the autonomic nervous system and chronobiology in the pathogenesis of congestive heart failure and response to therapy are also discussed. Establishing a novel model for overcoming diuretic resistance is presented based on a patient-tailored variability and chronotherapy-guided machine learning algorithm that comprises clinical, laboratory, and sensor-derived inputs, including inputs from pulmonary artery measurements. Inter- and intra-patient signatures of variabilities, alterations of biological clock, and autonomic nervous system responses are embedded into the algorithm; thus, it may enable a tailored dose regimen in a continuous manner that accommodates the highly dynamic complex system.

Tricuspid Regurgitation in Left Ventricular Systolic Dysfunction: Marker or Target?

Far from being historically considered a primary healthcare problem, tricuspid regurgitation (TR) has recently gained much attention from the scientific community. In fact, in the last years, robust evidence has emerged regarding the epidemiological impact of TR, whose prevalence seems to be similar to that of other valvulopathies, such as aortic stenosis, with an estimated up to 4% of people >75 years affected by at least moderate TR in the United States, and up to 23% among patients suffering from heart failure with reduced ejection fraction. This recurrent coexistence of left ventricular systolic dysfunction (LVSD) and TR is not surprising, considered the multiple etiologies of tricuspid valve disease. TR can complicate heart failure mostly as a functional disease, because of pulmonary hypertension (PH), subsequent to elevated left ventricular end-diastolic pressure, leading to right ventricular dilatation, and valve tethering. Moreover, the so-called "functional isolated" TR can occur, in the absence of PH, as a result of right atrial dilatation associated with atrial fibrillation, a common finding in patients with LVSD. Finally, TR can result as a iatrogenic consequence of transvalvular lead insertion, another frequent scenario in this cohort of patients. Nonetheless, despite the significant coincidence of these two conditions, their mutual relation, and the independent prognostic role of TR is still a matter of debate. Whether significant TR is just a marker for advanced left-heart disease, or a crucial potential therapeutical target, remains unclear. Aim of the authors in this review is to present an update concerning the epidemiological features and the clinical burden of TR in the context of LVSD, its prognostic value, and the potential benefit for early tricuspid intervention in patients affected by contemporary TR and LVSD.

Clinical significance of sFRP5, RBP-4 and NT-proBNP in patients with chronic heart failure

OBJECTIVE

This study was designed to investigate the levels and clinical significance of secretory frizzled-related protein 5 (sFRP5), retinol binding protein 4 (RBP-4) and N-terminal (NT)-pro hormone BNP (NT-proBNP) in patients with chronic heart failure (CHF).

METHODS

Eighty-nine patients with CHF treated in our hospital were included as the observation group. Seventy-five healthy volunteers who underwent physical examination in our hospital during the same period were selected as the control group. The subjects in the observation group were divided into NYHA class II (n=23), NYHA class III (n=34) and NYHA class IV (n=32) according to NYHA classification, and the levels of sFRP5, RBP-4 and NT-proBNP as well as left ventricular end-diastolic diameter (LVEDD) and left ventricular ejection fraction (LVEF) were compared in the three groups. Spearman correlation was used to analyze the relationship between sFRP5, RBP-4, NT-proBNP and LVEDD, LVEF. The ROC curves of sFRP5, RBP-4 and NT-proBNP for the diagnosis of CHF were plotted. Patients in the observation group were divided into a death group (n=30) and a survival group (n=59) according to the 1-year follow-up outcome, and the levels of sFRP5, RBP-4, and NT-proBNP were compared between the two groups.

RESULTS

The observation group showed significantly higher levels of sFRP5, RBP-4, NT-proBNP and LVEDD, and a significantly lower level of LVEF than the control group. Spearman's correlation analysis showed that sFRP5, RBP-4, NT-proBNP were correlated with LVEDD and LVEF in CHF patients (P < 0.05). The ROC curve showed that the AUC of sFRP5, RBP-4 and NT-proBNP for CHF diagnosis were 0.9378, 0.9133, and 0.9375, respectively. sFRP5, RBP-4, and NT-proBNP in the death group were all higher than those in the survival group (P < 0.05).

CONCLUSION

sFRP5, RBP-4, and NT-proBNP showed a close correlation with CHF. It is worthy of using this method as a clinical index for the diagnosis and prognosis of CHF.

Induction of renal tumor necrosis factor-α and other autacoids and the beneficial effects of hypertonic saline in acute decompensated heart failure

Although administration of hypertonic saline (HSS) in combination with diuretics has yielded improved weight loss, preservation of renal function, and reduction in hospitalization time in the clinical setting of patients with acute decompensated heart failure (ADHF), the mechanisms that underlie these beneficial effects remain unclear and additional studies are needed before this approach can be adopted on a more consistent basis. As high salt conditions stimulate the production of several renal autacoids that exhibit natriuretic effects, renal physiologists can contribute to the understanding of mechanisms by which HSS leads to increased diuresis both as an individual therapy as well as in combination with loop diuretics. For instance, since HSS increases TNF-α production by proximal tubule and thick ascending limb of Henle's loop epithelial cells, this article is aimed at highlighting how the effects of TNF-α produced by these cell types may contribute to the beneficial effects of HSS in patients with ADHF. Although TNF-α produced by infiltrating macrophages and T cells exacerbates and attenuates renal damage, respectively, production of this cytokine within the tubular compartment of the kidney functions as an intrinsic regulator of blood pressure and Na⁺ homeostasis via mechanisms along the nephron related to inhibition of Na⁺-K⁺-2Cl^- cotransporter isoform 2 activity and angiotensinogen expression. Thus, in the clinical setting of ADHF and hyponatremia, induction of TNF-α production along the nephron by administration of HSS may attenuate Na⁺-K⁺-2Cl^- cotransporter isoform 2 activity and angiotensinogen expression as part of a mechanism that prevents excessive Na⁺ reabsorption in the thick ascending limb of Henle's loop, thereby mitigating volume overload.

Regulation of Electrolyte Permeability by Herbal Monomers in Edematous Disorders

Edema is a gradual accumulation of fluid in the interstitial tissues or luminal cavities, which is regulated by ion transport pathways and reflects dysfunction of fluid and salt homeostasis. Increasing evidence suggests that some herbal monomers significantly reduce organ/tissue edema. In this review, we briefly summarized the electrolyte permeability involved in pathomechanisms of organ edema, and the benefits of herbal monomers on ionic transport machinery, including Na+-K+-ATPase, Na+ and Cl- channels, Na+-K+-2Cl- co-transporter, etc. Pharmaceutical relevance is implicated in developing advanced strategies to mitigate edematous disorders. In conclusion, the natural herbal monomers regulate electrolyte permeability in many edematous disorders, and further basic and clinical studies are needed.

The pathophysiology and management of diuretic resistance in patients with heart failure

OBJECTIVES

The objectives of the study are to investigate the causes of diuretic resistance in patients with advanced congestive heart failure (CHF), since diuretics are the cornerstone of treatment of these patients. Several studies have shown that diuretic resistance in patients with advanced CHF is common, ranging from 25% to 50% in hospitalized patients.

METHODS

In order to get a current perspective as to the magnitude of diuretic resistance in such patients, a focused Medline search of the English language literature was conducted between 2015 and 2020 using the search terms, CHF, diuretics, treatment, resistance, frequency, and 30 papers with pertinent information were selected.

RESULTS

The analysis of data from the selected papers demonstrated that diuretic resistance is common in hospitalized patients with advanced CHF and frequently associated with renal failure, which is secondary to CHF.

CONCLUSIONS

Diuretic resistance appears to be common in patients with advanced CHF and it is mostly due to decreased cardiac output, low blood pressure, decreased glomerular filtration rate, decreased filtration of sodium, and increased tubular reabsorption of sodium. Diuretic resistance in such patients can be overcome with the combination of loop diuretics with thiazide and thiazide-like diuretics, aldosterone antagonists, as well as other agents. The data from these studies in combination with collateral literature will be discussed in this review.

Clinical Characteristics of De Novo Heart Failure and Acute Decompensated Chronic Heart Failure: Are They Distinctive Phenotypes That Contribute to Different Outcomes?

Heart failure is currently one of the leading causes of morbidity and mortality. Patients with heart failure often present with acute symptoms and may have a poor prognosis. Recent evidence shows differences in clinical characteristics and outcomes between de novo heart failure (DNHF) and acute decompensated chronic heart failure (ADCHF). Based on a better understanding of the distinct pathophysiology of these two conditions, new strategies may be considered to treat heart failure patients and improve outcomes. In this review, the authors elaborate distinctions regarding the clinical characteristics and outcomes of DNHF and ADCHF and their respective pathophysiology. Future clinical trials of therapies should address the potentially different phenotypes between DNHF and ADCHF if meaningful discoveries are to be made.

Combination therapy of midodrine and droxidopa for refractory hypotension in heart failure with preserved ejection fraction per a pharmacist's proposal: a case report

Background

Patients with chronic heart failure (CHF) are often treated using many diuretics for symptom relief; however, diuretic use may have to continue despite hypotension development in these patients. Here, we present a case of heart failure with preserved ejection fraction (HFpEF), which is defined as ejection fraction ≥50% in CHF, and refractory hypotension, which was treated with midodrine and droxidopa to normalize blood pressure.

Case presentation

The patient was a 62-year-old man with a history of HFpEF due to mitral regurgitation and complaints of dyspnea on exertion. He had been prescribed multiple medications at an outpatient clinic for CHF management, including azosemide 60 mg/day, bisoprolol 2.5 mg/day, enalapril 2.5 mg/day, spironolactone 50 mg/day, and tolvaptan 15 mg/day. The systolic blood pressure (SBP) of the patient remained at 70–80 mmHg because the use of the diuretic could not be reduced or discontinued owing to edema and weight gain. He was hospitalized for the exacerbation of CHF. Although midodrine 8 mg/day was administered to improve hypotension, the SBP of the patient increased only up to 90 mmHg. On the 35th day after hospitalization, the urine volume decreased significantly (< 100 mL/day) due to hypotension. When droxidopa 200 mg/day replaced intravenous noradrenaline on the 47th day, the SBP remained at 100–120 mmHg and the urine volume increased.

Conclusions

Oral combination treatment with midodrine and droxidopa might contribute to the maintenance of blood pressure and diuretic activity in HFpEF patients with refractory hypotension. However, further long-term studies evaluating the safety and efficacy of this combination therapy for patients with HFpEF are needed.

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.

Dual Vasopressin Receptor Antagonism to Improve Congestion in Patients With Acute Heart Failure: Design of the AVANTI Trial

BACKGROUND

Loop diuretics are the main treatment for patients with acute heart failure, but are associated with neurohormonal stimulation and worsening renal function and do not improve long-term outcomes. Antagonists to arginine vasopressin may provide an alternative strategy to avoid these effects. The AVANTI study will investigate the efficacy and safety of pecavaptan, a novel, balanced dual-acting V1a/V2 vasopressin antagonist, both as adjunctive therapy to loop diuretics after admission for acute heart failure, and later as monotherapy.

METHODS AND RESULTS

AVANTI is a double-blind, randomized phase II study in 571 patients hospitalized with acute heart failure and signs of persistent congestion before discharge. In part A, patients will receive either pecavaptan 30 mg/d or placebo with standard of care for 30 days. In part B, eligible patients will continue treatment or receive pecavaptan or diuretics as monotherapy for another 30 days. The primary end points for part A are changes in body weight and serum creatinine; for part B, changes in body weight and blood urea nitrogen/creatinine ratio.

CONCLUSIONS

This study will provide the first evidence that a balanced V1a/V2 antagonist may safely enhance decongestion, both as an adjunct to loop diuretics and as an alternative strategy.

TRIAL REGISTRATION NUMBER

NCT03901729.

Diuretic Resistance in Heart Failure

Decompensated heart failure accounts for approximately 1 million hospitalizations in the United States annually, and this number is expected to increase significantly in the near future. Diuretics provide the initial management in most patients with fluid overload. However, the development of diuretic resistance remains a significant challenge in the treatment of heart failure. Due to the lack of a standard definition, the prevalence of this phenomenon remains difficult to determine, with some estimates suggesting that 25-30% of patients with heart failure have diuretic resistance. Certain characteristics, including low systolic blood pressures, renal impairment, and atherosclerotic disease, help predict the development of diuretic resistance. The underlying pathophysiology is likely multifactorial, with pharmacokinetic alterations, hormonal dysregulation, and the cardiorenal syndrome having significant roles. The therapeutic approach to this common problem typically involves increases in the diuretic dose and/or frequency, sequential nephron blockade, and mechanical fluid movement removal with ultrafiltration or peritoneal dialysis. Paracentesis is potentially useful in patients with intra-abdominal hypertension.

Successful treatment of refractory edema with traditional herbal medicine: A case report

RATIONALE

Refractory edema is characterized by persistent swelling which does not react to diuretic use and sodium restriction. Traditional herbal medicine, Gwack Rhyung Tang and Chunggan extract effectively treated refractory lower limb edema caused by cirrhosis and improved liver function.

PATIENT CONCERNS

A 64-year-old male patient with a history of hypertension, diabetes mellitus, hepatic encephalopathy, and cellulitis presented lower limb edema which did not react to diuretics for more than 7 months.

DIAGNOSES

Refractory edema caused by cirrhosis.

INTERVENTIONS

The patient was treated for 25 days using Gwack Rhyung Tang and Chunggan extract.

OUTCOMES

Loss of body weight, decrease in circumferences of both lower limb and improvement of liver function biochemistry results are checked. There was no recurrence or aggravation of the condition up to 3 weeks of follow-up periods.

LESSONS

Traditional herbal medicine can be an effective alternative for refractory edema due to cirrhosis with improving liver function.

Prognostic Significance of Longitudinal Clinical Congestion Pattern in Chronic Heart Failure: Insights From TIME-CHF Trial

BACKGROUND

The relationship between longitudinal clinical congestion pattern and heart failure outcome is uncertain. This study was designed to assess the prevalence of congestion over time and to investigate its impact on outcome in chronic heart failure.

METHODS

A total of 588 patients with chronic heart failure older than 60 years of age with New York Heart Association (NYHA) functional class ≥II from the TIME-CHF study were included. The endpoints for this study were survival and hospitalization-free heart failure survival. Orthopnea, NYHA ≥III, paroxysmal nocturnal dyspnea, hepatomegaly, peripheral pitting edema, jugular venous distension, and rales were repeatedly investigated and related to outcomes. These congestion-related signs and symptoms were used to design a 7-item Clinical Congestion Index.

RESULTS

Sixty-one percent of patients had a Clinical Congestion Index ≥3 at baseline, which decreased to 18% at month 18. During the median [interquartile range] follow-up of 27.2 [14.3-39.8] months, 17%, 27%, and 47% of patients with baseline Clinical Congestion Index of 0, 1-2, and ≥3 at inclusion, respectively, died (P <.001). Clinical Congestion Index was identified as an independent predictor of mortality at all visits (P <.05) except month 6 and reduced hospitalization-free heart failure survival (P <.05). Successful decongestion was related to better outcome as compared to persistent congestion or partial decongestion (log-rank P <0.001).

CONCLUSIONS

The extent of congestion as assessed by means of clinical signs and symptoms decreased over time with intensified treatment, but it remained present or relapsed in a substantial number of patients with heart failure and was associated with poor outcome. This highlights the importance of appropriate decongestion in chronic heart failure.

Diuretic Resistance in Cardio-Nephrology: Role of Pharmacokinetics, Hypochloremia, and Kidney Remodeling

Background: Diuretic resistance is among the most challenging problems that the cardio-nephrologist must address in daily clinical practice, with a considerable burden on hospital admissions and health care costs. Indeed, loop diuretics are the first-line therapy to overcome fluid overload in heart failure patients. The pathophysiological mechanisms of fluid and sodium retention are complex and depend on several neuro-hormonal signals mainly acting on sodium reabsorption along the renal tubule. Consequently, doses and administration modalities of diuretics must be carefully tailored to patients in order to overcome under- or overtreatment. The frequent and tricky development of diuretic resistance depends in part on post-diuretic sodium retention, reduced tubular secretion of the drug, and reduced sodium/chloride sensing. Sodium and chloride depletions have been recently shown to be major factors mediating these processes. Aquaretics and high-saline infusions have been recently suggested in cases of hyponatremic conditions. This review discusses the limitations and strengths of these approaches. Summary: Long-term diuretic use may lead to diuretic resistance in cardio-renal syndromes. To overcome this complication intravenous administration of loop diuretics and a combination of different diuretic classes have been proposed. In the presence of hyponatremia, high-saline solutions in addition to loop diuretics might be beneficial, whereas aquaretics require caution to avoid overcorrection. Key Messages: Diuretic resistance is a central theme for cardio-renal syndromes. Hyponatremia and hypochloremia may be part of the mechanisms for diuretic resistance. Aquaretics and high-saline solutions have been proposed as possible new therapeutic solutions.

N-Aryl-7-hydroxy-5-oxo-2,3-dihydro-1H,5H-pyrido-[3,2,1-ij]quinoline-6-carboxamides. The Synthesis and Effects on Urinary Output

Continuing a targeted search for new leading structures with diuretic action among tricyclic derivatives of hydroxyquinolines, which are of interest as potential inhibitors of aldosterone synthase, the synthesis of a series of the corresponding pyrido[3,2,1-ij]quinoline-6-carboxanilides was carried out by amidation of ethyl-7-hydroxy-5-oxo-2,3-dihydro-1H,5H-pyrido[3,2,1-ij]quinoline-6-carboxylate with aniline, aminophenols and O-alkylsubstituted analogs with high yields and purity. The optimal conditions of this reaction are proposed; they make it possible to prevent partial destruction of the original heterocyclic ester and thereby avoid formation of specific impurities of 7-hydroxy-2,3-dihydro-1H,5H-pyrido[3,2,1-ij]quinolin-5-one. To confirm the structure of all substances obtained, elemental analysis, nuclear magnetic resonance (NMR) spectroscopy, and mass spectrometry were used. Moreover, the peculiarities of their ¹H and 13C-NMR spectra, as well as their mass spectrometric behavior under conditions of electron impact ionization, were discussed. The effect of pyrido[3,2,1-ij]quinoline-6-carboxanilides on the urinary function of the kidneys was studied in white rats of both genders by the standard method of oral administration at a dose of 10 mg/kg. Testing was conducted in comparison with hydrochlorothiazide, as well as with structurally close pyrrolo[3,2,1-ij] quinoline-5-carboxanilides studied earlier with the same substituents in the anilide fragments. It was found that addition of one methylene unit to the heterocycle partially hydrogenated and annelated with the quinolone core has a positive impact on biological properties-most of the substances studied exhibit a statistically significant diuretic effect exceeding the activity of not only hydrochlorothiazide, in some cases, but also the action of the structural analogs. The important structural and biological regularities, which are common with pyrroloquinolines and introduced by a chemical modification, were revealed. The importance of the presence in the structure of terminal amide fragments of tricyclic quinoline-3-carboxamides of a 4-methoxy-substituted aromatic ring was particularly marked. The expediency of further study of pyridoquinolines as promising diuretic agents has been shown.