Better late than never: the true results of CARRESS-HF

Contemporary Decongestive Strategies in Acute Heart Failure

Congestion is the primary driver of hospital admissions in patients with heart failure and the key determinant of their outcome. Although intravenous loop diuretics remain the predominant agents used in the setting of acute heart failure, the therapeutic response is known to be variable, with a significant subset of patients discharged from the hospital with residual hypervolemia. In this context, urinary sodium excretion has gained attention both as a marker of response to loop diuretics and as a marker of prognosis that may be a useful clinical tool to guide therapy. Several decongestive strategies have been explored to improve diuretic responsiveness and removal of excess fluid. Sequential nephron blockade through combination diuretic therapy is one of the most used methods to enhance natriuresis and counter diuretic resistance. In this article, I provide an overview of the contemporary decongestive approaches and discuss the clinical data on the use of add-on diuretic therapy. I also discuss mechanical removal of excess fluid through extracorporeal ultrafiltration with a brief review of the results of landmark studies. Finally, I provide a short overview of the strategies that are currently under investigation and may prove helpful in this setting.

Ultrafiltration for patients with acute decompensated heart failure: A systematic review and meta-analysis

BACKGROUND

Ultrafiltration plays an indispensable role in relieving congestion and fluid retention in patients with acute decompensated heart failure (ADHF) in recent years. So far, there is no consistent agreement about whether early ultrafiltration (UF) is a first-line treatment for patients with ADHF. We, therefore, conducted a meta-analysis to assess the efficacy and safety of UF.

METHODS

PubMed, Embase, and Cochrane Library databases were searched for randomized controlled trials (RCTs) that compared UF with diuretics in patients with ADHF and included our interested outcomes. The primary outcomes are heart failure rehospitalization, all-cause rehospitalization, and mortality. The second outcomes are fluid loss, weight loss, and adverse events. RevMan Version 5.4.1 was used to analyze the data of included studies.

RESULTS

A total of 12 studies with 1197 patients were included. Our results showed a reduction in heart failure rehospitalization (risk ratio [RR] 0.67, 95% confidence interval [CI]: 0.52-0.87, P = .003) and all-cause rehospitalization (RR 0.62, 95% CI: 0.42-0.92; P = .02), an increase in fluid loss (1.47 L, 95% CI: 0.95-1.99 L, P < .001) and weight loss (1.65 kg, 95% CI: 0.90-2.41 kg; P < .001). There was no difference in mortality (RR 1.09, 95% CI: 0.78-1.51; P = .62). There were inconsistent agreements about which group have more total adverse events. Subgroup analysis showed that UF with larger mean fluid-remove rate (≥200 mL/h) could significantly remove more fluid, lose more weight, and decrease heart failure rehospitalization. Less weight loss for patients with ADHF may correlated to higher percent of ischemic etiology (ischemic etiology ≥50%).

CONCLUSION

Although UF is more effective in removing fluid than diuretics and decrease rehospitalization of heart failure and all causes, there is not enough evidence to prove that UF is superior because of adverse events and mortality in the UF group. The mean fluid-removal rates should be set to ≥200 mL/h. Patient with different etiology may have different effects when treated with UF and it is a weak conclusion.Trial registration: The systematic review was registered with the International Prospective Registry of Systematic Reviews. (https://www.crd.york.ac.uk/prospero/, registration number CRD42021245049).

The Cardiorenal Syndrome in Heart Failure

Abnormal fluid handling leads to physiologic abnormalities in multiple organ systems. Deranged hemodynamics, neurohormonal activation, excessive tubular sodium reabsorption, inflammation, oxidative stress, and nephrotoxic medications are important drivers of harmful cardiorenal interactions in patients with heart failure. Accurate quantitative measurement of fluid volume is vital to individualizing therapy for such patients. Blood volume analysis and pulmonary artery pressure monitoring seem the most reliable methods for assessing fluid volume and guiding decongestive therapies. Still the cornerstone of decongestive therapy, diuretics' effectiveness decreases with progression of heart failure. Extracorporeal ultrafiltration, an alternative to diuretics, has been shown to reduce heart-failure events.

Ultrafiltration for the Treatment of Acute Heart Failure

Ultrafiltration (UF) mechanically removes excess fluid volume through an extracorporeal circuit and has been applied to clinical situations in which volume removal is the mainstay of therapy. Because of this ability, UF serves as an enticing method to treat acute heart failure (AHF) in which most symptoms are driven by congestion due to excess volume. Additional physiologic properties of UF and the biochemical composition of the extracted fluid confer additional theoretic benefits in the treatment of AHF. Herein the concepts underlying UF, clinical evidence evaluating its efficacy, and ongoing challenges understanding the role of UF are reviewed.

Extracorporeal Isolated Ultrafiltration for Management of Congestion in Heart Failure and Cardiorenal Syndrome

Acute decompensated heart failure has the highest rate of hospital readmission among all medical conditions and portends a significant financial burden on health care system. Congestion, the hallmark of acute decompensated heart failure, represents the primary reason for hospitalization and the driver of adverse outcomes in these patients. Although diuretic-based medical regimens remain the mainstay of management of acute decompensated heart failure, they often show suboptimal efficacy and safety profiles in this setting. Mechanical extraction of excess fluid through extracorporeal ultrafiltration therapy has been proposed as a mechanistically relevant option in this setting. The advent of simplified, portable, and user-friendly devices that are dedicated to ultrafiltration therapy for these patients has renewed the interest in this therapeutic modality. In this article, we provide a brief overview of the initial mechanistic studies followed by the key clinical findings of the most recent landmark trials. The shortcomings of these studies are discussed in detail because not only do they provide the appropriate context in which the results are to be interpreted, but more importantly they also highlight the existing knowledge gaps that need to be addressed in future studies. Finally, selected practical and conceptual considerations and controversies are reviewed with regard to evidence-based ultrafiltration therapy.