Association between diuretic use, clinical response, and death in acute heart failure

Tidal peritoneal dialysis versus ultrafiltration in type 1 cardiorenal syndrome: A prospective randomized study

Background:

Ultrafiltration is an alternative strategy to diuretic therapy for the treatment of patients with acute decompensated heart failure. Little is known about the efficacy and safety of peritoneal dialysis in patients with acute decompensated heart failure complicated by acute cardiorenal syndrome.

Methods:

We randomly assigned a total of 88 patients with type 1 acute cardiorenal syndrome to a strategy of ultrafiltration therapy (44 patients) or tidal peritoneal dialysis (44 patients). The primary endpoint was the change from baseline in the serum creatinine level and left ventricular function represented as ejection fraction, as assessed 72 and 120 h after random assignment. Patients were followed for 90 days after discharge from the hospital.

Results:

Ultrafiltration therapy was inferior to tidal peritoneal dialysis therapy with respect to the primary endpoint of the change in the serum creatinine levels at 72 and 120 h ( p = 0.041) and ejection fraction at 72 and 120 h after enrollment ( p = 0.044 and p = 0.032), owing to both an increase in the creatinine level in the ultrafiltration therapy group and a decrease in its level in the tidal peritoneal dialysis group. At 120 h, the mean change in the creatinine level was 1.4 ± 0.5 mg/dL in the ultrafiltration therapy group, as compared with 2.4 ± 1.3 mg/dL in the tidal peritoneal dialysis group ( p = 0.023). At 72 and 120 h, there was a significant difference in weight loss between patients in the ultrafiltration therapy group and those in the tidal peritoneal dialysis group ( p = 0.025). Net fluid loss was also greater in tidal peritoneal dialysis patients ( p = 0.018). Adverse events were more observed in the ultrafiltration therapy group ( p = 0.007). At 90 days post-discharge, tidal peritoneal dialysis patients had fewer rehospitalization for heart failure (14.3% vs 32.5%, p = 0.022).

Conclusion:

Tidal peritoneal dialysis is a safe and effective means for removing toxins and large quantities of excess fluid from patients with intractable heart failure. In patients with cardiorenal syndrome type 1, the use of tidal peritoneal dialysis was superior to ultrafiltration therapy for the preservation of renal function, improvement of cardiac function, and net fluid loss. Ultrafiltration therapy was associated with a higher rate of adverse events.

Association between loop diuretic dose administered in first 24 hours of heart failure admissions and length of hospital stay

Background: Heart failure remains one of the highest disease burdens in the USA and worldwide. Heart failure guidelines recommend starting with a higher or equal to home dose of loop diuretics in acute decompensated heart failure admissions. To date, no study has been published assessing the effect of first 24 h loop diuretic dose on length of hospital stay. Objective: We hypothesize that the higher the first 24 h loop diuretic dose to home dose ratio, the shorter the length of hospital stay will be. Design/Methods: Retrospective chart review was conducted in a community teaching hospital and included patients discharged between February, 2015 and April, 2016, with a primary diagnosis of acute decompensated heart failure. The primary outcome was the length of hospital stay. The study population was divided into three groups based on the hospital to home dose ratio. Results: Among the 609 patients included in the data analysis, there was no statistically significant difference in length of hospital stay among the study groups. Inpatient mortality and incidence of acute kidney injury were highest in the group that received a first-24-hours hospital dose that was less than their home dose. Percentage of weight loss and 30-day readmission were not statistically significantly different among the groups. Conclusion: There was no association between the dose ratio and length of hospital stay in each group. Additional randomized controlled trials need to be conducted to provide more evidence and guidance for dosing loop diuretics in acute decompensated heart failure admissions.

Elevated serum uric acid concentration at discharge confers additive prognostic value in elderly patients with acute heart failure

BACKGROUND AND AIMS

Elevated serum uric acid (sUA) concentrations have been associated with worse prognosis in heart failure (HF) but little is known about elderly patients. We aimed to assess long-term additive prognostic value of sUA in elderly patients hospitalized for HF.

METHODS AND RESULTS

Clinical and echocardiographic characteristics of 310 consecutive elderly patients hospitalized for HF were collected. During index period, 206 had sUA concentrations available, which were obtained within 24 h prior to discharge; 10 patients were lost to follow-up, leaving 196 patients available. Patients had a median age of 77 (IQR 69-83) years, and were mostly male (64.5%). sUA ranges for tertiles I-III were: 1.5-6.1, 6.2-8.3, and 8.4-18.9 mg/dl, respectively. During a median follow-up of 27 months (IQR 10.5-39.5), 122 combined events occurred (87 deaths and 73 HF rehospitalizations). Four-year event-free survival for the combined endpoint was 46 ± 7% for tertile I, 34 ± 7% for tertile II, and 21 ± 5% for tertile III (P = 0.001). By multivariable Cox backward analysis, sUA was retained as a significant predictor. Compared with the lowest sUA tertile, tertile III showed a strong association with outcome, also after adjustment for other predictors (HR 1.84, 95% CI 1.16-2.93; P = 0.01). Importantly, addition of sUA to the other significant predictors of outcome resulted in improved risk classification (net reclassification improvement 0.19, P = 0.017).

CONCLUSIONS

High sUA at discharge is a strong predictor of adverse outcome in elderly hospitalized for HF, and it significantly improves risk classification. Measuring sUA can be a simple and useful tool to identify high-risk elderly hospitalized for HF.

Effect of the angiotensin receptor-neprilysin inhibitor sacubitril/valsartan on the pharmacokinetics and pharmacodynamics of a single dose of furosemide

Aims

Sacubitril/valsartan is indicated for the treatment of heart failure and reduced ejection fraction (HFrEF). Furosemide, a loop diuretic commonly used for the treatment of HFrEF, may be coadministered with sacubitril/valsartan in clinical practice. The effect of sacubitril/valsartan on the pharmacokinetics and pharmacodynamics of furosemide was evaluated in this open label, two‐period, single‐sequence study in healthy subjects.

Methods

All subjects (n = 28) received 40 mg oral single‐dose furosemide during period 1, followed by a washout of 2 days. In period 2, sacubitril/valsartan 200 mg (97/103 mg) was administered twice daily for 5 days and a single dose of 40 mg furosemide was coadministered on day 6. Serial plasma and urine samples were collected to determine the pharmacokinetics of furosemide and sacubitril/valsartan and the pharmacodynamics of furosemide. The point estimates and the associated 90% confidence intervals for pharmacokinetic parameters were evaluated.

Results

Coadministration of furosemide with sacubitril/valsartan decreased the maximum observed plasma concentration (C_max) [estimated geometric mean ratio (90% confidence interval): 0.50 (0.44, 0.56)], area under the plasma concentration–time curve (AUC) from time 0 to infinity [0.72 (0.67, 0.77)] and 24‐h urinary excretion of furosemide [0.74 (0.69, 0.79)]. When coadministered with sacubitril/valsartan, 0–4‐h, 4–8‐h and 0–24‐h diuresis in response to furosemide was reduced by ~7%, 21% and 0.2%, respectively, while natriuresis was reduced by ~ 28.5%, 7% and 15%, respectively. Post hoc analysis of the pivotal phase III Prospective comparison of ARNI with ACEI to Determine Impact on Global Mortality and morbidity in Heart Failure trial (PARADIGM‐HF) indicated that the median furosemide dose was similar at baseline and at the end of the study in the sacubitril/valsartan group.

Conclusions

Sacubitril/valsartan reduced plasma C_max and AUC and 24‐h urinary excretion of furosemide, while not significantly affecting its pharmacodynamic effects in healthy subjects.

Impact of Cardiorenal Anemia Syndrome on Short- and Long-Term Clinical Outcomes in Patients Hospitalized with Heart Failure

BACKGROUND

Dysfunctional interplay between the heart and kidneys may lead to the development of anemia. The aim of this study was to evaluate the impact of cardiorenal anemia syndrome (CRAS) on short- and long-term outcomes among patients hospitalized with heart failure (HF).

METHODS

We enrolled 303 patients hospitalized with HF. We divided the patients into two groups: a CRAS group (n = 64) and a non-CRAS group (n = 239). We defined CRAS as HF accompanied by (1) an estimated glomerular filtration rate <60 ml/min/1.73 m(2) calculated by the Modification of Diet in Renal Disease at admission and (2) a hemoglobin level <12 g/dl for females and <13 g/dl for males at admission. The primary outcome was a composite of cardiac death, non-fatal myocardial infarction and rehospitalization for HF.

RESULTS

During a median follow-up period of 25.6 months (range 0.1-35.3 months), the patients with CRAS had a significantly increased risk for the primary outcome (27.5 vs. 10.7%, p < 0.001) compared with the patients in the non-CRAS group. Using Cox proportional hazard analyses, the hazard ratio (HR) for the presence of CRAS was found to be 1.874 (95% confidence interval [CI] 1.011-3.475, p = 0.046); HRs were also computed for the presence of diabetes mellitus (HR = 2.241, 95% CI 1.221-4.112, p = 0.009), New York Heart Association class III or IV HF (HR = 2.948, 95% CI 1.206-7.205, p = 0.018) and the use of intravenous loop diuretics (HR = 2.286, 95% CI 0.926-5.641, p = 0.073).

CONCLUSIONS

Renal dysfunction and anemia are a fatal combination and are associated with poor prognosis in patients with HF.

Combination decongestion therapy in hospitalized heart failure: loop diuretics, mineralocorticoid receptor antagonists and vasopressin antagonists

Congestion is the most common reason for admissions and readmissions for heart failure (HF). The vast majority of hospitalized HF patients appear to respond readily to loop diuretics, but available data suggest that a significant proportion are being discharged with persistent evidence of congestion. Although novel therapies targeting congestion should continue to be developed, currently available agents may be utilized more optimally to facilitate complete decongestion. The combination of loop diuretics, natriuretic doses of mineralocorticoid receptor antagonists and vasopressin antagonists represents a regimen of currently available therapies that affects early and persistent decongestion, while limiting the associated risks of electrolyte disturbances, hemodynamic fluctuations, renal dysfunction and mortality.

Ultrafiltration versus intravenous diuretic therapy to treat acute heart failure: a systematic review

BACKGROUND

Patients with decompensated heart failure frequently present with volume overload, which is conventionally treated with diuretics. These drugs have been associated with several adverse effects, including increased mortality, leading some clinicians to propose ultrafiltration as a safe alternative to remove sodium and water.

OBJECTIVE

The objective of our study was to compare the safety and efficacy of ultrafiltration and conventional intravenous diuretic therapy for patients with acute heart failure and volume overload.

DATA SOURCES

We searched the following databases through November 2012: Cochrane Library (1993-), PubMed (1988-), OVID (1984-), EBSCO (1984-), CBM (1978-), VIP (1989-), and CNKI (1979-). In addition, we manually searched relevant references and review articles.

STUDY SELECTION

Randomized controlled trials comparing the efficacy of ultrafiltration and intravenous diuretics in patients diagnosed with hypervolemic acute heart failure were included. Five trials were found to satisfy all the inclusion criteria.

STUDY APPRAISAL AND SYNTHESIS METHODS

Two reviewers independently determined study eligibility, assessed methodological quality and extracted the data. We analyzed the data and pooled them, when appropriate, using Revman 5.0. We assessed the risk of bias in the included studies using guidelines in the Cochrane Handbook 5.0 for Systematic Reviews of Interventions, taking into account sequence generation, allocation concealment, blinding, incomplete outcome data, and selective outcome reporting.

RESULTS

Data from the initial phase of five trials involving 477 participants were included. Meta-analysis of the pooled data showed that ultrafiltration was significantly better than diuretic drugs based on 48-h weight loss (Z = 3.72; P < 0.001, weighted mean difference [WMD] = 1.25 kg, 95 % CI 0.59-1.91) and based on 48-h fluid removal (Z = 4.23; P < 0.001, WMD = 1.06 L, 95 % CI 0.57-1.56). Adverse events did not differ significantly between the ultrafiltration and intravenous diuretic treatment groups.

LIMITATIONS

There are several limitations to our review, including publication bias and selection bias. Our review included only a few studies involving relatively few participants.

CONCLUSIONS

The available evidence suggests that early ultrafiltration is safe and effective for patients with hypervolemic acute heart failure. It allows greater fluid removal and weight loss by 48 h than do intravenous diuretics, with no significant increase in adverse effects.

Loop diuretics and ultrafiltration in heart failure

INTRODUCTION

Despite widespread use of loop diuretics in congestive heart failure (HF) to achieve decongestion and relief of symptoms, as recommended by the current guidelines, there is uncertainty as to their long-term therapeutic efficacy and safety. Their efficacy and safety compared to venous ultrafiltration are currently under investigation in acute decompensated HF patients.

AREAS COVERED

In this article, the authors review current available data related to efficacy and safety of loop diuretics and ultrafiltration in HF.

EXPERT OPINION

The literature review highlights an unmet clinical need for evidence-based algorithms, potentially using not only the classical clinical signs and symptoms of congestion as well as the estimated glomerular filtration rate and serum electrolytes, but also biomarkers of congestion/decongestion, neurohumoural activation or urinary kidney injury molecules, in order to optimize both loop diuretics and renin-angiotensin-aldosterone system blocker use in HF patients.

Troponin I release after intravenous treatment with high furosemide doses plus hypertonic saline solution in decompensated heart failure trial (Tra-HSS-Fur)

BACKGROUND

High values of cardiac troponin in acute decompensated congestive heart failure (ADHF) identify patients at higher risk and worsened prognosis. A cardiac troponin increase during therapy indicates the need for more appropriate intervention, aimed at compensating cardiac disease and effectively minimizing myocardial wall stress and subsequent cytolysis. This study evaluated the effects of an intravenous high dose of furosemide with (group A) or without small volume hypertonic saline solution (HSS) (group B) on myocardial cytolysis in patients with ADHF.

METHODS

A total of 248 consecutive patients with ADHF (148 men, mean age 74.9 ± 10.9 years) were randomly assigned to group A or B. Plasma levels of cardiac troponin-I, brain natriuretic peptide, glomerular filtration rate by Modification of Diet in Renal Disease formula, bioelectrical impedance analysis measurements, and delta pressure/delta time (dP/dt) rate were observed on admission and discharge for all patients.

RESULTS

We observed a significant reduction of cardiac troponin in both groups and a significant improvement in renal function, hydration state, pulmonary capillary wedge pressure (P < .0001), end diastolic volume (P < .01), ejection fraction (P < .01), and dP/dt (P < .004) in group A. We also observed a significant reduction in body weight (64.4 vs 75.8 kg) (P < .001), cardiac troponin I (0.02 vs 0.31 ng/mL) (P < .0001) and brain natriuretic peptide (542 vs 1,284 pg/mL) (P < .0001), and hospitalization time (6.25 vs 10.2 days) (P < .0001) in the HSS group.

CONCLUSIONS

These data demonstrate that intravenous high doses of furosemide do not increase myocardial injury and, in addition, when associated to HSS, significantly reduce cardiac troponin I release. This behavior is mirrored by the achievement of improved hemodynamic compensation at echocardiography and body hydration normalization.

Determinants and Consequences of Renal Function Variations With Aldosterone Blocker Therapy in Heart Failure Patients After Myocardial Infarction

Background—

We evaluated the effect of the selective mineralocorticoid receptor antagonist eplerenone on renal function and the interaction between changes in renal function and subsequent cardiovascular outcomes in patients with heart failure and left ventricular systolic dysfunction after an acute myocardial infarction in the Eplerenone Post–Acute Myocardial Infarction Heart Failure Efficacy and Survival Study (EPHESUS).

Methods and Results—

Serial changes in estimated glomerular filtration rate (eGFR) were available in 5792 patients during a 24-month follow-up. Patients assigned to eplerenone had a decline in eGFR with an adjusted mean difference of −1.4±0.3 mL · min −1 · 1.73 m −2 compared with placebo ( P <0.0001), an effect that appeared within the first month (−1.3±0.4 mL · min −1 · 1.73 m −2 ) and persisted throughout the study. Overall, 914 patients experienced a decline in eGFR >20% in the first month, 16.9% and 14.7% in the eplerenone and placebo groups, respectively (odds ratio, 1.15; 95% confidence interval, 1.02–1.30; P =0.017). In multivariate analyses, determinants of this early decline in eGFR were female sex, age ≥65 years, smoking, left ventricular ejection fraction <35%, and use of eplerenone and loop diuretic. An early decline in eGFR by >20% was associated with worse cardiovascular outcomes independently of baseline eGFR and of the use of eplerenone, which retained its prognostic benefits even under these circumstances.

Conclusions—

In patients with heart failure after acute myocardial infarction and receiving standard medical care, an early decline in eGFR is not uncommon and is associated with poor long-term outcome. Eplerenone induced a moderately more frequent early decline in eGFR, which did not affect its clinical benefit on cardiovascular outcomes.

Metabolic and toxicological considerations for diuretic therapy in patients with acute heart failure

INTRODUCTION

Diuretics are widely recommended in patients with acute heart failure (AHF). However, loop diuretics predispose patients to electrolyte imbalance and hypovolemia, which in turn leads to neurohormonal activation and worsening renal function (WRF). Unfortunately, despite their widespread use, limited data from randomized clinical trials are available to guide clinicians with the appropriate management of this diuretic therapy.

AREAS COVERED

This review focuses on the current management of diuretic therapy and discusses data supporting the efficacy and safety of loop diuretics in patients with AHF. The authors consider the challenges in performing clinical trials of diuretics in AHF, and describe ongoing clinical trials designed to rigorously evaluate optimal diuretic use in this syndrome. The authors review the current evidence for diuretics and suggest hypothetical bases for their efficacy relying on the complex relationship among diuretics, neurohormonal activation, renal function, fluid and sodium management, and heart failure syndrome.

EXPERT OPINION

Data from several large registries that evaluated diuretic therapy in hospitalized patients with AHF suggest that its efficacy is far from being universal. Further studies are warranted to determine whether high-dose diuretics are responsible for WRF and a higher rate of coexisting renal disease are instead markers of more severe heart failure. The authors believe that monitoring congestion during diuretic therapy in AHF would refine the current approach to AHF treatment. This would allow clinicians to identify high-risk patients and possibly reduce the incidence of complications secondary to fluid management strategies.

Pathogenesis and therapeutic implications of cardiorenal syndrome

Chronic kidney disease (CKD) is now widely accepted as a risk factor for cardiovascular disease and mortality. Heart failure patients with CKD have a worse prognosis. The heart and kidneys act in tandem to regulate blood pressure, vascular tone, diuresis, natriuresis, intravascular volume homeostasis, peripheral tissue perfusion, and oxygenation. Cardiorenal syndrome is a pathophysiological condition in which combined cardiac and renal dysfunction amplifies the progression of failure of the individual organs, and it has an extremely poor prognosis. The identification of patients and the pathophysiological mechanisms underlying each subtype will help physicians to understand the clinical derangements and provide the rationale for management strategies. The evidence from clinical trials conducted on heart failure patients with significant kidney dysfunction is insufficient because most patients are recruited from populations with relatively well-preserved kidney function. In severe volume-loaded patients who are refractory to diuretics and also have kidney dysfunction, the management of cardiorenal dysfunction is challenging, and effective therapy is lacking. In the absence of definitive clinical trials, treatment decisions must be based on a combination of information regarding the individual patient information and an understanding of the individual treatment options.

Loop diuretic therapy in heart failure: the need for solid evidence on a fluid issue

BACKGROUND

Heart failure (HF) is a common condition associated with substantial cost, morbidity, and mortality. Because results of clinical trials in the acute decompensated heart failure (ADHF) setting have been mostly neutral, loop diuretics remain the mainstay of treatment.

HYPOTHESIS

Loop diuretic use may be associated with unfavorable outcomes.

METHODS

A MEDLINE literature search was performed to identify articles relating to heart failure and loop diuretics. The current evidence on the risks and benefits of loop diuretics for the treatment of ADHF is reviewed.

RESULTS

Loop diuretics are associated with symptomatic improvements in congestion, urine output, and body weight, but have shown no long-term mortality benefit. Loop diuretics, especially at high doses, are associated with worsened renal function and other poor outcomes.

CONCLUSIONS

Loop diuretics still prove useful in HF treatment, but risk-benefit analysis of these agents in the treatment of ADHF requires a well-designed prospective study.

The critical link of hypervolemia and hyponatremia in heart failure and the potential role of arginine vasopressin antagonists

BACKGROUND

Hypervolemia and hyponatremia resulting from activation of the neurohormonal system and impairment of renal function are prominent features of decompensated heart failure. Both conditions share many pathophysiologic and prognostic features and each has been associated with increased morbidity and mortality. When both conditions coexist, therapeutic options are limited.

METHODS AND RESULTS

This review presents a concise digest of the pathophysiology, clinical significance, and pharmacological therapy of hyponatremia complicating heart failure with a special emphasis on vasopressin antagonists and their aquaretic effects in the absence of neurohormonal activation along with their ability to correct hyponatremia.

CONCLUSIONS

Hypervolemia and hyponatremia share many pathophysiologic and prognostic features in heart failure. Vasopressin antagonists provide a viable option for their management and a potentially unique role when both conditions coexists.

Early pharmacological treatment of acute heart failure syndromes: A systematic review of clinical trials

CONTEXT

Acute Heart Failure Syndromes (AHFS) is a common admission diagnosis associated with high mortality and hospital readmissions. Given the mixed results of recent clinical trials, the early management of AHFS remains controversial.

OBJECTIVE

To review the recent evidence regarding current and investigational therapies for the early management of AHFS.

DATA SOURCES

A systematic search of peer-reviewed publications was performed on MEDLINE and EMBASE from January 1990 to August 2006. The results of unpublished or ongoing trials were obtained from presentations at national and international meetings and pharmaceutical industry releases. Bibliographies from these references were also reviewed, as were additional articles identified by content experts.

STUDY SELECTION AND DATA EXTRACTION

Criteria used for study selection were controlled study design, relevance to clinicians and validity based on venue of publication and power analysis.

DATA SYNTHESIS

Although all current intravenous therapies for the early management of AHFS appear to improve hemodynamics, this may not always translate into short-term clinical benefit.

CONCLUSION

The results of the trials conducted to date in AHFS have generally been disappointing. There is, therefore, an unmet need for new therapeutic approaches for the early management of AHFS that may improve the short-term and long-term outcomes.

Ultrafiltration in the management of heart failure

PURPOSE OF REVIEW

Congestion causes the majority of hospitalizations for heart failure and contributes to heart failure progression and mortality. Intravenous loop diuretics reduce the signs and symptoms of congestion. Loop diuretics, however, may be associated with increased morbidity and mortality because of deleterious effects on neurohormonal activation, electrolyte balance, and cardiac and renal function. Ultrafiltration, an alternative method of sodium and water removal, safely improves hemodynamics in heart failure patients.

RECENT FINDINGS

The Ultrafiltration versus Intravenous Diuretics for Patients Hospitalized for Acute Decompensated Heart Failure trial has recently shown that among 200 volume overloaded heart failure patients randomized to ultrafiltration or intravenous diuretics, 48 h weight (P = 0.001) and net fluid loss (P = 0.001) were greater in the ultrafiltration group. Dyspnea scores were similar. At 90 days, the ultrafiltration group had fewer heart failure rehospitalizations/patient (P = 0.022) and patients presenting for unscheduled visits (21 vs. 44%; P = 0.009). No serum creatinine differences occurred between the groups.

SUMMARY

In decompensated heart failure, ultrafiltration safely produces greater weight and fluid loss than intravenous diuretics, reduces rehospitalization rates for heart failure and is an effective alternative therapy.

Role of tolvaptan in acute decompensated heart failure

Acute decompensated heart failure accounts for more than 1 million hospitalizations in the USA every year. Currently, the most common treatment for symptom relief is the use of loop diuretics, despite recent concerns for potential adverse effects. With the growing understanding of the role of neurohormonal dysregulation in the pathophysiology of heart failure, there has been increasing interest in novel pharmacologic therapies targeting specific neurohormonal axes. Serum arginine vasopressin is a potent vasoconstrictor, as well as an antidiuretic, and serum concentrations are upregulated in heart failure. Tolvaptan, a vasopressin receptor antagonist, has been shown to improve diuresis and symptom relief without adversely affecting renal function, and may be a promising novel therapeutic agent in the growing population of patients with heart failure.

Acute cardio-renal syndrome: Progression from congestive heart failure to congestive kidney failure

Over the past few years, acute worsening of renal function has emerged as a powerful and independent predictor of adverse cardiac outcomes among patients hospitalized with acute heart failure exacerbation. This phenomenon has been recently termed acute cardio-renal syndrome. Acute cardio-renal syndrome is not uncommon, affecting roughly one third of acute decompensated heart failure patients. The mechanism of acute cardio-renal syndrome is poorly understood and difficult to elucidate in light of the complex and multifactorial comorbidities associated with acute heart failure syndrome. Acute cardio-renal syndrome is commonly explained by hypoperfusion of the kidney with intravascular volume depletion, hypotension and low flow state ("pre-renal syndrome"). This perception, however, is challenged by the actual hemodynamics present during acute cardio-renal syndrome characterized by hypervolemia, normal cardiac output, and elevated filling pressures of the systemic and venous circulation. This review discusses the long-standing and unnoticed evidence in support of the notion that right-sided failure with raised filling pressure of the renal vein by itself can indeed lead to acute worsening renal function with oliguria, azotemia, and reduced glomerular filtration rate.

Broken pump or leaky filter? Renal dysfunction in heart failure a contemporary review

Renal dysfunction is a frequent and progressive complication of chronic heart failure and is a powerful predictor of cardiovascular mortality. It is intimately associated with cardiovascular disease even in its earliest stages. Although cardiovascular and renal disease share many risk factors, the prognostic implications do not simply reflect widespread atherosclerotic vascular disease as this appears to be as important in those with heart failure secondary to idiopathic dilated cardiomyopathy as it is in those with coronary artery disease. There may be a role in the progression of heart failure, as the deleterious effects of even "mild" renal impairment seem to be borne out in predicting outcome, in a broad range of heart failure patients including those with heart failure and preserved systolic function. Renal dysfunction is both an indication for, as well as frequently limiting intervention with intensive disease modifying therapy. Although renal impairment is common in heart failure and these patients are at higher risk for adverse events including death, they are under represented in clinical trials.

Practical applications of intravenous diuretic therapy in decompensated heart failure

Intravenous (IV) loop diuretics play an important role in the treatment of decompensated heart failure (DHF). They inhibit the Na(+)-K(+)-2Cl(-) reabsorptive pump in the thick ascending limb of the loop of Henle, and the resultant natriuresis and diuresis decreases volume load, improves hemodynamics, and reduces DHF symptoms. However, loop diuretics have a short half-life and their efficacy may be limited by postdiuretic sodium rebound during the period between doses in which the tubular diuretic concentration is subtherapeutic. Moreover, they can produce electrolyte abnormalities, neurohormonal activation, intravascular volume depletion, and renal dysfunction. Several studies have reported an association between diuretic therapy and increased morbidity and mortality. In addition, many patients, especially those with more advanced forms of heart failure (HF), are resistant to standard doses of loop diuretics. These high-risk, resistant patients may benefit from pharmacologic and/or nonpharmacologic interventions to improve hemodynamic performance, treatment of renovascular disease, discontinuation of aspirin and other sodium-retaining drugs, manipulation of the route of delivery or combination of diuretic classes, or hemofiltration. Despite >50 years of use, many questions regarding the use of intravenous diuretic agents in patients with DHF are still unanswered, and there remains a compelling need for well-designed randomized, controlled clinical trials to establish appropriate treatment regimens that maximize therapeutic benefit while minimizing morbidity and mortality.

Beyond diuretics: management of volume overload in acute heart failure syndromes

Diuretics are an established foundation of therapy for patients with chronic heart failure (HF) as well as for those hospitalized for treatment of acute HF syndromes. Despite the accepted use of diuretics in acute HF syndromes, treatment patterns with diuretics vary widely, and there are no data from randomized studies on the benefit of diuretics on morbidity or mortality in patients hospitalized with acute HF syndromes. Additional pharmacologic therapies that complement or replace diuretics in this setting, especially in patients with diuretic resistance, include positive inotropes, nitrovasodilators, and natriuretic peptides, but data are likewise lacking on important clinical outcomes. Ultrafiltration has also been used as a nonpharmacologic strategy to treat patients with acute HF syndromes who exhibit resistance to diuretics. Effective monitoring of volume status with newer modalities may allow more selective use of diuretics and diuretic-like modalities, but additional randomized trial data are clearly needed to establish ideal strategies to promote volume removal in acute HF syndromes.

The role of ultrafiltration in the management of heart failure

In the United States, 90% of one million annual hospitalizations for heart failure are due to symptoms of volume overload. Hypervolemia contributes to heart failure progression and mortality. Treatment guidelines recommend that therapy for patients with heart failure be aimed at achieving euvolemia. Intravenous loop diuretics induce a rapid diuresis that reduces lung congestion and dyspnea. However, loop diuretics' effectiveness declines with repeated exposure. Unresolved congestion may contribute to high re-hospitalization rates. Furthermore, loop diuretics may be associated with increased morbidity and mortality due to deleterious effects on neurohormonal activation, electrolyte balance, and cardiac and renal function. Ultrafiltration is an alternative method of sodium and water removal, which safely improves hemodynamics in patients with heart failure. Application of this technology has been limited by the need for high flow rates, large extracorporeal blood volumes, and large-bore central venous catheters. A modified ultrafiltration device has overcome these limitations. Ultrafiltration may be a safe and effective alternative to intravenous diuretics in the treatment of decompensated heart failure.

Tolvaptan: a selective vasopressin type 2 receptor antagonist in congestive heart failure

The neurohormone arginine vasopressin plays a significant role in the regulation of volume homeostasis, which is mediated via vasopressin type 2 (V2) receptors in the collecting tubules of the kidney. Diseases that are accompanied by abnormal volume homeostasis, including congestive heart failure and cirrhosis, are a frequent cause of hospital admissions and increasing healthcare costs. Recently, several nonpeptide V2 receptor antagonists have emerged as promising agents in the management of these conditions with the advantage of having no electrolyte abnormalities, neurohormonal activation or worsening renal insufficiency. Tolvaptan, a highly selective nonpeptide V2 receptor antagonist, has demonstrated an improvement in the volume status, osmotic balance and haemodynamic profile in preclinical and Phase II trials in patients with congestive heart failure and is currently undergoing testing in Phase III trials. This review discusses the evidence for the potential uses of tolvaptan, and its pharmacology and pharmacokinetics, particularly in congestive heart failure.

Overview of vasopressin receptor antagonists in heart failure resulting in hospitalization

Patients with worsening heart failure (HF) requiring hospitalization commonly have a history of progressive fluid retention, decreased renal function, and hyponatremia. For these patients, diuretics have traditionally been the mainstay of treatment, but they are associated with electrolyte abnormalities and impaired renal function. Previous studies have shown that levels of the endogenous arginine vasopressin (AVP) hormone are elevated in patients with HF and may be the contributing factor to fluid retention and hyponatremia, and probably progression of HF. Vasopressin antagonists represent a unique class of therapeutic agents because of their potential role in both the short- and long-term treatment of patients hospitalized with worsening HF. As "aquaretics," AVP antagonists offer the possibility of added efficacy in relieving congestion and improving symptoms with minimal adverse effects in combination with standard medical therapy. Some AVP receptor antagonists have shown promising results in animal studies and small-scale clinical trials. The purpose of this review was to update the current status of studies with the available AVP antagonists.

Role of vasopressin antagonists in the management of acute decompensated heart failure

Vasopressin antagonists are a class of neurohormonal antagonists with applications in both the short-term and long-term management of patients with acute decompensated heart failure (ADHF). The pharmacologic effects of vasopressin antagonists include changes in fluid balance and hemodynamics that may improve symptoms and outcomes in patients hospitalized with ADHF. With chronic therapy, vasopressin antagonists offer the potential to improve outcomes through a variety of mechanisms, including more effective treatment of congestion, preservation or improvement of renal function, or a reduction in the use of concomitant loop diuretic therapy. Several vasopressin antagonists are currently in advanced clinical trials for the treatment of ADHF, chronic stable heart failure, and hyponatremia.

The use of recombinant human B-type natriuretic peptide (nesiritide) in the management of acute decompensated heart failure

Nesiritide is a synthetic human B-type natriuretic factor that has a balanced arterial and venous dilator effect, with natriuretic, diuretic, anti-aldosterone and antisympathetic action. It was launched in the US for the treatment of acute decompensated heart failure (ADHF) in August 2001 and, recently, in Switzerland and Israel. It has been demonstrated to provide more rapid and sustained haemodynamic stabilisation than glyceryl trinitrate and significant symptomatic improvement vs. placebo at 3 h, and to be safer than dobutamine. The main side effects associated with nesiritide therapy are asymptomatic and symptomatic hypotension, which are treated with dose reduction. When compared to dobutamine, the increased acquisition costs of nesiritide are completely offset by reduced intensity of hospital admissions and reduced readmission rate at 3 weeks.

Searching for evidence: refractory questions in advanced heart failure

BACKGROUND

Despite ample data from randomized clinical trials (RCTs), the management of advanced heart failure (HF) varies greatly. We examined the most common refractory questions arising in routine inpatient management of advanced HF.

METHODS

From the inpatient HF service at 1 hospital, we prospectively recorded clinical questions arising for which there were no clear answers available about HF management. When possible, patients received angiotensin-converting enzyme (ACE) inhibitors, beta-blockers, and spironolactone as used in RCTs. We identified the topics and frequencies of questions and categorized them as Group 1--whether to use a therapy--or Group 2--how to use a therapy.

RESULTS

During 2 separate months, 318 questions arose among 57 patients. The most common topics involved the use of diuretics, potassium, and ACE inhibitors, most often about how to titrate diuretics, what targets to use to optimize diuretic therapy, and how to select discharge doses of diuretics. Questions of whether to use a therapy occurred 73 times, and how to use a therapy, 242 times. RCT data were difficult to apply to these questions because little information exists about how to combine and titrate HF drugs and how to adjust diuretics. Questions about individual drugs arose in patients who fell outside the average RCT entry criteria for age, blood pressure, and creatinine.

CONCLUSION

Most refractory questions focused on how to integrate and adjust therapies within the overall medical regimen and how to apply data to patients not represented in RCTs. Future studies should evaluate strategies of care for the advanced HF population.

A rational approach for the treatment of acute heart failure: current strategies and future options

PURPOSE OF REVIEW

Acute decompensated heart failure represents a major, growing health problem in the developed world. However, until recently, relatively little research has been performed in this field to provide a basis for rational treatment strategies. The purpose of this review is to discuss the current approach and the potential future strategies for treatment of patients with acute decompensated heart failure.

RECENT FINDINGS

Recent data have confirmed the heterogeneous nature of patients admitted with acute decompensated heart failure, and the limitations of the current therapeutic regimens with diuretics, intravenous vasodilators (ie, nitroglycerin, nitroprusside), and intravenous inotropes (ie, dobutamine, milrinone). A new vasodilator, nesiritide, has been demonstrated to improve hemodynamics and symptoms at 3 hours compared with nitroglycerin, and has been added to the therapeutic armamentarium in the United States. However, none of these agents has been shown to influence patient outcomes favorably. Given the high readmission rates, morbidity, and mortality of acute decompensated heart failure, other newer approaches, such as antagonists to a number of neurohumoral targets (ie, endothelin [tezosentan], vasopressin [conivaptan, tolvaptan], and adenosine) and non-cAMP-mediated inotropy (ie, levosimendan), are currently under investigation and showing promise.

SUMMARY

Acute decompensated heart failure presents a challenging therapeutic problem for clinicians. Although they readily correct the hemodynamic abnormalities, current treatment strategies have significant limitations and have not been shown to improve morbidity or mortality. A number of new agents are under investigation with the goal of improving patient outcomes.

Renal effects of adenosine A1-receptor antagonists in congestive heart failure

Renal function is a very important prognostic indicator in patients with congestive heart failure. While some of the prognostic importance of poor renal function is related to the worse physiology associated with it, there are suggestions that the dysfunction itself is detrimental. Recently, it has been shown that adenosine may mediate much kidney activity. In addition to vasoconstrictive and vasodilatory effects, adenosine is intrinsic to the tubuloglomerular feedback which occurs when an acute increase in sodium levels in the proximal tubule feeds back to decrease glomerular filtration. Adenosine works via both adenosine A1 and A2 receptors. A1-receptor antagonists decrease afferent arteriolar pressure, and increase urine flow and sodium excretion. Studies suggest that A1-receptor antagonists cause a diuretic effect not by a change in the renal haemodynamics, but by the inhibition of water and sodium reabsorption in tubular sites secondary to direct tubuloglomerular feedback. Less consistent has been the occasional finding of increased glomerular filtration rate despite the lack of improved renal plasma flow. Clinically important questions are: what role adenosine plays in causing the poor renal function associated with heart failure and what A1-receptor antagonists do in such situations? If an A1-receptor antagonist could cause diuresis while maintaining or improving glomerular filtration, it would be a useful adjunct in the treatment of severe heart failure. We evaluated the effects of the A1-receptor antagonist CVT-124 (BG-9719) in heart failure patients. CVT-124 increased sodium excretion without decreasing glomerular filtration rate. These data suggest that adenosine might be an important determinant of renal function in patients with heart failure.

Determinants of angiotensin-converting enzyme inhibitor prescription in severe heart failure with left ventricular systolic dysfunction: the EPICAL study

BACKGROUND

Angiotensin-converting enzyme (ACE) inhibitors have been demonstrated to reduce morbidity and mortality rates in patients with heart failure with left ventricular systolic dysfunction. Nevertheless, these drugs are underutilized in current practice and prescribed at doses below those usually recommended. The aim of this work was to identify the social, demographic, laboratory, clinical, and therapeutic factors associated with nonprescription of ACE inhibitors and/or their prescription at doses below those recommended in the treatment of severe long-term congestive heart failure (CHF).

METHODS AND RESULTS

An epidemiologic observational study, EPICAL (EPidémiologie de l'Insuffisance Cardiaque Avancée en Lorraine), studied 417 patients with severe CHF surviving after the index hospitalization. Multivariate logistic regression determined the factors associated with ACE inhibitor nonprescription and with their prescription at lower-than-recommended doses. ACE inhibitors were taken by 75% of the patients but 38% took lower-than-recommended doses. Factors shown to be associated with nonprescription included patients >65 years of age with renal impairment (odds ratio 19.5, confidence interval [CI] 7.9-48.0), nonsinus cardiac rhythm (odds ratio 2.0, CI 1.2-3.2), and prescription of potassium-sparing diuretics (odds ratio 2.4, CI 1. 2-4.7). Renal impairment was the single most important factor associated with prescription of lower-than-recommended doses, particularly in elderly patients.

CONCLUSIONS

Our results underline the need for optimal and better use of ACE inhibitor therapy. CHF treatment guidelines must be more uniformly applied by all physicians caring for patients with heart failure.

Comprehensive multidisciplinary programs for the management of patients with congestive heart failure

OBJECTIVE

To evaluate the impact of comprehensive, multidisciplinary management programs on the process of care, resource utilization, health care costs, and clinical outcomes in patients with congestive heart failure.

MEASUREMENTS AND MAIN RESULTS

A MEDLINE search identified seven english-language reports that compared the process of care, clinical outcomes, or economic variables related to implementation of a multidisciplinary congestive heart failure management program of at least 3 month's duration to a control or reference group. The primary intent of the programs was to emphasize compliance with recommended therapeutic principles, enhance patient education, and provide careful patient surveillance. Five of the studies reported improved functional status, aerobic capacity, or patient satisfaction. Six of the studies reported a 50% to 85% reduction in the risk of hospital admission. Three studies reported economic analyses with suggestive but not compelling evidence of financial benefit.

CONCLUSIONS

Comprehensive, multidisciplinary management programs for congestive heart failure can improve functional status and reduce the risk of hospital admission, and they may lower medical costs.