Spironolactone metabolite concentrations in decompensated heart failure: insights from the ATHENA-HF trial

The utility of urine sodium-guided diuresis during acute decompensated heart failure

Diuresis to achieve decongestion is a central aim of therapy in patients hospitalized for acute decompensated heart failure (ADHF). While multiple approaches have been tried to achieve adequate decongestion rapidly while minimizing adverse effects, no single diuretic strategy has shown superiority, and there is a paucity of data and guidelines to utilize in making these decisions. Observational cohort studies have shown associations between urine sodium excretion and outcomes after hospitalization for ADHF. Urine chemistries (urine sodium ± urine creatinine) may guide diuretic titration during ADHF, and multiple randomized clinical trials have been designed to compare a strategy of urine chemistry-guided diuresis to usual care. This review will summarize current literature for diuretic monitoring and titration strategies, outline evidence gaps, and describe the recently completed and ongoing clinical trials to address these gaps in patients with ADHF with a particular focus on the utility of urine sodium-guided strategies.

Strategies for the Management of Cardiorenal Syndrome in the Acute Hospital Setting

Cardiorenal syndrome (CRS) is a life-threatening disorder that involves a complex interplay between the two organs. Managing this multifaceted syndrome is challenging in the hospital and requires a multidisciplinary approach to tackle the many manifestations and complications. There is no universally accepted algorithm to treat patients, and therapeutic options vary from one patient to another. The mainstays of therapy involve the stabilization of hemodynamics, decongestion using diuretics or renal replacement therapy, improvement of cardiac output with inotropes, and goal-directed medical treatment with renin–angiotensin–aldosterone system inhibitors, beta-blockers, and other medications. Mechanical circulatory support is another viable option in the armamentarium of agents that improve symptoms in select patients.

Increased Spironolactone Dosing in Acute Heart Failure Alters Potassium Homeostasis but Does not Enhance Decongestion

BACKGROUND

The ATHENA-HF (Aldosterone Targeted Neurohormonal Combined with Natriuresis Therapy in Heart Failure) clinical trial found no improvements in natriuretic peptide levels or clinical congestion when spironolactone 100 mg/day for 96 hours was used in addition to usual treatment for acute heart failure.

METHODS

We performed a post hoc analysis of ATHENA-HF to determine whether spironolactone treatment induced any detectable pharmacodynamic effects and whether patients with potentially greater aldosterone activity experienced additional decongestion. Trial subjects previously treated with spironolactone were excluded. We first examined for changes in renal potassium handling. Using the baseline serum potassium level as a surrogate marker of spironolactone activity, we then divided each treatment arm into tertiles of baseline serum potassium and explored for differences in laboratory and clinical congestion outcomes.

RESULTS

Among spironolactone-naïve patients, the change in serum potassium did not differ after 24 hours or 48 hours but was significantly greater with spironolactone treatment compared to placebo at 72 hours (0.23 ± 0.55 vs 0.03 ± 0.60 mEq/L; P = 0.042) and 96 hours (0.32 ± 0.51 vs 0.13 ± 0.72 mEq/L; P = 0.046). Potassium supplementation was similar at treatment start and at 24 hours, but spironolactone-treated patients required substantially less potassium replacement at 48 hours (24% vs 36%; P = 0.048), 72 hours (21% vs 37%; P = 0.013), and 96 hours (11% vs 38%; P < 0.001). When the treatment arms were divided into tertiles of baseline serum potassium, there were no differences in the 96-hour log N-terminal pro-B-type natriuretic peptide levels, net fluid loss, urine output, or dyspnea relief in any of the potassium groups, with no effect modification by treatment exposure.

CONCLUSIONS

Spironolactone 100 mg/day for 96 hours in patients receiving intravenous loop diuresis for acute heart failure has no clear added decongestive ability but does meaningfully limit potassium wasting.

Spironolactone metabolite causes falsely increased progesterone in the Abbott Architect immunoassay

BACKGROUND

Immunoassays are important for routine clinical testing and medical diagnosis. However, they are limited by cross-reactivity especially at low analyte concentrations. There is a critical need to investigate compounds that can interfere with immunoassays. Herein, we describe the identification of canrenone, a spironolactone metabolite that falsely increases progesterone concentrations on the Abbott Architect i2000 Immunoassay.

METHODS

Serum samples and assay diluents were spiked with spironolactone or canrenone and progesterone concentrations were measured on the Architect i2000 and Immulite XPi immunoassay platforms. Blood samples from patients taking spironolactone were analyzed with liquid chromatography-tandem mass spectrometry to evaluate the intrinsic response of progesterone concentrations to the presence of canrenone.

RESULTS

We measured approximately 10-fold higher progesterone concentrations on the Abbott Architect i2000 compared to reference immunoassay analyzers (Siemens Immulite XPi and Roche Cobas e601/602), suggesting an analytical error which is unique to the Architect i2000 antibody and/or assay conditions. By measuring serum progesterone after addition of spironolactone or canrenone to serum samples, we found that canrenone falsely increased progesterone on the Architect i2000 immunoassay. However, this interference was more pronounced at low serum progesterone concentrations. Moreover, a strong positive correlation was seen between canrenone and measured serum progesterone concentrations.

CONCLUSIONS

Our investigations are important for individuals who require progesterone measurements using the Architect i2000 immunoassay, especially because it is unlikely for clinicians to order canrenone measurements alongside progesterone measurements for individuals taking spironolactone. Further research is needed to determine whether canrenone can influence progesterone measurements on other immunoassay systems.

Eco-friendly solvent bar microextraction based on a natural deep eutectic solvent and multivariate optimization for simultaneous determination of spironolactone and canrenone in urine and plasma samples

Simultaneous measurement of spironolactone and canrenone in urine and plasma provides valuable insight into renal function, and therapeutic efficacy and can be utilized to identify potential health risks and ensure patient safety throughout treatment. By adopting greener methods to analyze these compounds, significant reductions in the environmental impact of such studies can be achieved. For this purpose, a sensitive and eco-friendly solvent bar microextraction method using natural deep eutectic solvent (NDE) followed by high-performance liquid chromatography-diode array detection (HPLC-DAD) was developed to determine spironolactone and canrenone in urine and plasma samples. The extraction solvents were synthesized using NDE-based terpenoids containing menthol and camphor in various ratios. The extraction efficiency percentage (EE%) of both drugs was measured using response surface methodology (RSM) based on central composite design (CCD), and 29 extraction tests were conducted to determine the optimum conditions. Although all parameters were found to be significant, the extraction and elution times were critical for isolating the target analytes. Under optimized conditions, the linear dynamic ranges for spironolactone (SPI)/canrenone (CAN) were 11.7-104/13.1-104 μg L-1 and 21.7-104/24.6-104 μg L-1 in urine and plasma samples, respectively with R2 ≥ 0.993. The ranges of intra-/interprecision (relative standard deviation (RSD) %, n = 5) were 1.31-9.17%/ 2.4-11% with extraction recovery ≥ 88.6% for both drugs. The comparison findings with previously published methods confirmed that the developed NDE-solvent bar microextraction (SBME)-HPLC-DAD method for spironolactone and canrenone analysis displayed confident sensitivity, feasible operation, and simple analysis. Furthermore, the method's applicability and effectiveness were proven by successfully analyzing spironolactone and its metabolite canrenone in patients' urine and plasma samples.

Renin-Angiotensin-Aldosterone System Activation and Diuretic Response in Ambulatory Patients With Heart Failure

Rationale & Objective

Heart failure treatment relies on loop diuretics to induce natriuresis and decongestion, but the therapy is often limited by diuretic resistance. We explored the association of renin-angiotensin-aldosterone system (RAAS) activation with diuretic response.

Study Design

Observational cohort.

Setting & Population

Euvolemic ambulatory adults with chronic heart failure were administered torsemide in a monitored environment.

Predictors

Plasma total renin, active renin, angiotensinogen, and aldosterone levels. Urine total renin and angiotensinogen levels.

Outcomes

Sodium output per doubling of diuretic dose and fractional excretion of sodium per doubling of diuretic dose.

Analytical Approach

Robust linear regression models estimated the associations of each RAAS intermediate with outcomes.

Results

The analysis included 56 participants, and the median age was 65 years; 50% were women, and 41% were Black. The median home diuretic dose was 80-mg furosemide equivalents. In unadjusted and multivariable-adjusted models, higher levels of RAAS measures were generally associated with lower diuretic efficiency. Higher plasma total renin remained significantly associated with lower sodium output per doubling of diuretic dose (β = -0.41 [-0.76, -0.059] per SD change) with adjustment; higher plasma total and active renin were significantly associated with lower fractional excretion of sodium per doubling of diuretic dose (β = -0.48 [-0.83, -0.14] and β = -0.51 [-0.95, -0.08], respectively) in adjusted models. Stratification by RAAS inhibitor use did not substantially alter these associations.

Limitations

Small sample size; highly selected participants; associations may not be causal.

Conclusions

Among multiple measures of RAAS activation, higher plasma total and active renin levels were consistently associated with lower diuretic response. These findings highlight the potential drivers of diuretic resistance and underscore the need for high-quality trials of decongestive therapy enhanced by RAAS blockade.

Classic and Novel Mechanisms of Diuretic Resistance in Cardiorenal Syndrome

Despite the incompletely understood multiple etiologies and underlying mechanisms, cardiorenal syndrome is characterized by decreased glomerular filtration and sodium avidity. The underlying level of renal sodium avidity is of primary importance in driving a congested heart failure phenotype and ultimately determining the response to diuretic therapy. Historically, mechanisms of kidney sodium avidity and resultant diuretic resistance were primarily extrapolated to cardiorenal syndrome from non-heart failure populations. Yet, the mechanisms appear to differ between these populations. Recent literature in acute decompensated heart failure has refuted several classically accepted diuretic resistance mechanisms and reshaped how we conceptualize diuretic resistance mechanisms in cardiorenal syndrome. Herein, we propose an anatomically based categorization of diuretic resistance mechanisms to establish the relative importance of specific transporters and translate findings toward therapeutic strategies. Within this categorical structure, we discuss classic and novel mechanisms of diuretic resistance.

Quantification and treatment of congestion in heart failure: A clinical and pathophysiological overview

Renal sodium and water retention with resulting extracellular volume expansion and redistribution are hallmark features of heart failure syndromes. However, congestion assessment, monitoring, and treatment represent a real challenge in daily clinical practice. This document reviewed historical and contemporary evidence of available methods for determining volume status and discuss pharmacological aspects and pathophysiological principles that underlie diuretic use.

Medical management of acute heart failure

Despite recent advances in the treatment of chronic heart failure, therapeutic options for acute heart failure (AHF) remain limited. AHF admissions are associated with significant multi-organ dysfunction, especially worsening renal failure, which results in significant morbidity and mortality. There are several aspects of AHF management: diagnosis, decongestion, vasoactive therapy, goal-directed medical therapy initiation and safe transition of care. Effective diagnosis and prognostication could be very helpful in an acute setting and rely upon biomarker evaluation with noninvasive assessment of fluid status. Decongestive strategies could be tailored to include pharmaceutical options along with consideration of utilizing ultrafiltration for refractory hypervolemia. Vasoactive agents to augment cardiac function have been evaluated in patients with AHF but have shown to only have limited efficacy. Post stabilization, initiation of quadruple goal-directed medical therapy—angiotensin receptor-neprilysin inhibitors, mineral receptor antagonists, sodium glucose type 2 (SGLT-2) inhibitors, and beta blockers—to prevent myocardial remodeling is being advocated as a standard of care. Safe transition of care is needed prior to discharge to prevent heart failure rehospitalization and mortality. Post-discharge close ambulatory monitoring (including remote hemodynamic monitoring), virtual visits, and rehabilitation are some of the strategies to consider. We hereby review the contemporary approach in AHF diagnosis and management.

Multinephron Segment Diuretic Therapy to Overcome Diuretic Resistance in Acute Heart Failure: A Single-Center Experience

BACKGROUND

The concept of multinephron segment diuretic therapy (MSDT) has been recommended in severe diuretic resistance with only expert opinion and case-level evidence. The purpose of this study was to investigate the safety and efficacy of MSDT, combining 4 diuretic classes, in acute heart failure (AHF) complicated by diuretic resistance.

METHODS AND RESULTS

A retrospective analysis was conducted in patients hospitalized with AHF at a single medical center who received MSDT, including concomitant carbonic anhydrase inhibitor, loop, thiazide, and mineralocorticoid receptor antagonist diuretics. Subjects served as their own controls with efficacy evaluated as urine output and weight change before and after MSDT. Serum chemistries, renal replacement therapies, and in-hospital mortality were evaluated for safety. Patients with severe diuretic resistance before MSDT were analyzed as a subcohort. A total of 167 patients with AHF and diuretic resistance received MSDT. MSDT was associated with increased median 24-hour urine output in the first day of therapy compared with the previous day (2.16 L [0.95-4.14 L] to 3.08 L [1.74-4.86 L], P = .003) in the total cohort and in the Severe diuretic resistance cohort (0.91 L [0.43-1.43 L] to 2.08 L [1.13-3.96 L], P < .001). The median cumulative weight loss at day 7 or discharge was -7.4 kg (-15.3 to -3.4 kg) (P = .02). Neither serum sodium, chloride, potassium, bicarbonate, or creatinine changed significantly relative to baseline (P > .05 for all).

CONCLUSIONS

In an AHF cohort with diuretic resistance, MSDT was associated with increased diuresis without changes in serum chemistries or kidney function. Prospective studies of MSDT in AHF and diuretic resistance are warranted.

Quantification and Treatment of Congestion in Heart Failure: A Clinical and Pathophysiological Overview

Renal sodium and water retention with resulting extracellular volume expansion and redistribution are hallmark features of heart failure syndromes. However, congestion assessment, monitoring, and treatment represent a real challenge in daily clinical practice. This document reviewed historical and contemporary evidence of available methods for determining volume status and discuss pharmacological aspects and pathophysiological principles that underlie diuretic use.