Potential advantages of torsemide in patients with heart failure: more than just a 'water pill'?

Cutting the Gordian knot of diuretic resistance using continuous ultrafiltration in a Holt-Oram patient with decompensated heart failure and Eisenmenger syndrome: a case report

Background

Continuous ultrafiltration consists a decongestion method for patients with refractory decompensated heart failure with diuretic resistance as it enables the energetic withdrawal of isotonic fluid under controlled rate according to the patient's vital signs, offering decongestion without exceeding plasma refill rate.

Case summary

A 62-year-old male with history of Holt-Oram syndrome with Eisenmenger physiology presented with worsening dyspnoea. Patient initial clinical and laboratory examination, renal vein ultrasound, and echocardiogram were consistent with significant congestion. A combined strategy of intravenous furosemide with early initiation of continuous ultrafiltration at an adjustable rate for 4 days was finally selected. Patient remained haemodynamically stable during the total treatment time and exhibited significant clinical and laboratory improvement. Consecutive renal vein ultrasounds and echocardiograms demonstrated a continuous and steady recession of congestion. During the 4 days of ultrafiltration, total fluid loss was estimated at 42 L. Patient remained asymptomatic without signs of worsened congestion at 1, 3, and 5 months follow-up.

Discussion

Our case depicts that continuous ultrafiltration without exceeding plasma refill rate allows an impaired right ventricle to maintain significant preload. This suggests that it might be considered for patients in whom a session of short classic ultrafiltration might have detrimental results regarding cardiac output.

Temporal trends in evidence supporting therapeutic interventions in heart failure and other European Society of Cardiology guidelines

AIMS

This study aimed to determine whether any change occurred over time in level of evidence (LoE) of therapeutic interventions supporting heart failure (HF) and other European Society of Cardiology guideline recommendations.

METHODS AND RESULTS

We selected topics with at least three documents released between 2008 and April 2022. Classes of recommendations (CoR) and supporting LoE related to therapeutic interventions within each document were collected and compared over time. A total of 1822 recommendations from 18 documents on 6 topics [median number per document = 112, 867 (48%) CoR I] were included in the analysis. There was a trend towards a reduction over time in the percentage of CoR I in HF (46-36-34%), non-ST elevation myocardial infarction (NSTEMI; 78-58-54%), and pulmonary embolism (PE; 65-50-39%) guidelines, with a decrease in the total number of recommendations for HF only. Percentage of CoR I was stable over time around 40% for valvular heart disease (VHD) and atrial fibrillation (AF), and around 60% for cardiovascular prevention (CVP), with an increase in the total number of recommendations for VHD and CVP and a decrease for AF. Among CoR I, 319 (37%) were supported by LoE A, with a decrease over time for HF (56-46-42%), an increase for NSTEMI (29-38-48%) and AF (28-31-36%), a bimodal distribution for PE and CVP, and a lack for VHD.

CONCLUSIONS

LoE supporting therapeutic recommendations in contemporary European guidelines is generally low. Physicians should be aware of these limitations, and scientific societies promote a greater understanding of their significance and drive future research directions.

Effect of Torsemide Versus Furosemide on Symptoms and Quality of Life Among Patients Hospitalized for Heart Failure: The TRANSFORM-HF Randomized Clinical Trial

BACKGROUND

Loop diuretics are a primary therapy for the symptomatic treatment of heart failure (HF), but whether torsemide improves patient symptoms and quality of life better than furosemide remains unknown. As prespecified secondary end points, the TRANSFORM-HF trial (Torsemide Comparison With Furosemide for Management of Heart Failure) compared the effect of torsemide versus furosemide on patient-reported outcomes among patients with HF.

METHODS

TRANSFORM-HF was an open-label, pragmatic, randomized trial of 2859 patients hospitalized for HF (regardless of ejection fraction) across 60 hospitals in the United States. Patients were randomly assigned in a 1:1 ratio to a loop diuretic strategy of torsemide or furosemide with investigator-selected dosage. This report examined effects on prespecified secondary end points, which included Kansas City Cardiomyopathy Questionnaire Clinical Summary Score (KCCQ-CSS; assessed as adjusted mean difference in change from baseline; range, 0-100 with 100 indicating best health status; clinically important difference, ≥5 points) and Patient Health Questionnaire-2 (range, 0-6; score ≥3 supporting evaluation for depression) over 12 months.

RESULTS

Baseline data were available for 2787 (97.5%) patients for KCCQ-CSS and 2624 (91.8%) patients for Patient Health Questionnaire-2. Median (interquartile range) baseline KCCQ-CSS was 42 (27-60) in the torsemide group and 40 (24-59) in the furosemide group. At 12 months, there was no significant difference between torsemide and furosemide in change from baseline in KCCQ-CSS (adjusted mean difference, 0.06 [95% CI, -2.26 to 2.37]; P=0.96) or the proportion of patients with Patient Health Questionnaire-2 score ≥3 (15.1% versus 13.2%: P=0.34). Results for KCCQ-CSS were similar at 1 month (adjusted mean difference, 1.36 [95% CI, -0.64 to 3.36]; P=0.18) and 6-month follow-up (adjusted mean difference, -0.37 [95% CI, -2.52 to 1.78]; P=0.73), and across subgroups by ejection fraction phenotype, New York Heart Association class at randomization, and loop diuretic agent before hospitalization. Irrespective of baseline KCCQ-CSS tertile, there was no significant difference between torsemide and furosemide on change in KCCQ-CSS, all-cause mortality, or all-cause hospitalization.

CONCLUSIONS

Among patients discharged after hospitalization for HF, a strategy of torsemide compared with furosemide did not improve symptoms or quality of life over 12 months. The effects of torsemide and furosemide on patient-reported outcomes were similar regardless of ejection fraction, previous loop diuretic use, and baseline health status.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03296813.

Pragmatic Design of Randomized Clinical Trials for Heart Failure: Rationale and Design of the TRANSFORM-HF Trial

Randomized clinical trials are the foundation of evidence-based medicine and central to practice guidelines and patient care decisions. Nonetheless, randomized trials in heart failure (HF) populations have become increasingly difficult to conduct and are frequently associated with slow patient enrollment, highly selected populations, extensive data collection, and high costs. The traditional model for HF trials has become particularly difficult to execute in the United States, where challenges to site-based research have frequently led to modest U.S. representation in global trials. In this context, the TRANSFORM-HF (Torsemide Comparison with Furosemide for Management of Heart Failure) trial aims to overcome traditional trial challenges and compare the effects of torsemide versus furosemide among patients with HF in the United States. Loop diuretic agents are regularly used by most patients with HF and practice guidelines recommend optimal use of diuretic agents as key to a successful treatment strategy. Long-time clinical experience has contributed to dominant use of furosemide for loop diuretic therapy, although preclinical and small clinical studies suggest potential advantages of torsemide. However, due to the lack of appropriately powered clinical outcome studies, there is insufficient evidence to conclude that torsemide should be routinely recommended over furosemide. Given this gap in knowledge and the fundamental role of loop diuretic agents in HF care, the TRANSFORM-HF trial was designed as a prospective, randomized, event-driven, pragmatic, comparative-effectiveness study to definitively compare the effect of a treatment strategy of torsemide versus furosemide on long-term mortality, hospitalization, and patient-reported outcomes among patients with HF. (TRANSFORM-HF: ToRsemide compArisoN With furoSemide FORManagement of Heart Failure [TRANSFORM-HF]; NCT03296813).

Pharmacogenetics as a Way for Personalizing Diuretic Therapy: Focus on Torasemide

Optimizing diuretic therapy in patients with chronic heart failure is a complicated problem with many unresolved questions. Diuretics take an important place in the treatment of heart failure, which are used in almost 80% of cases. Currently, there are not enough clinical studies, which comparative effectiveness of loop diuretics, as well as studies aimed at personalizing diuretic therapy. Torasemide has several advantages over other loop diuretics; high bioavailability, longer half-life and duration of action provide predictable diuresis. The presence of favorable neurohormonal effects, consisting in a decrease of sympathetic activity and inhibition of the renin-angiotensin-aldosterone system, leads to the fact that hypokalemia rarely occurs. In addition, torasemide slows development of myocardial fibrosis and fosters reverse ventricular remodelling. The use of personalization methods is one of the ways to increase the efficiency and safety of pharmacotherapy with diuretics. The polymorphism of genes encoding systems of biotransformation and transporters of drug is an important factor that determines the individual characteristics of a patient. Pharmacogenetics of torasemide may be of significant importance for pharmacokinetics and pharmacodynamics, influencing the intensity of the diuretic effect and side effects. The clearance of torasemide after oral administration may vary by 47% due to genetic characteristics: the participation of the OATP1B1 polymorphism is approximately 15.5%, the CYP2C9 polymorphism is 20%, and the OAT1 and OAT4 polymorphisms are 10%. Due to the significant differences in the pharmacokinetics of torasemide, further study of the pharmacodynamic characteristics of torasemide in patients with genetic polymorphism is necessary.

Angiotensin Receptor Neprilysin Inhibitors in HFrEF: Is This the First Disease Modifying Therapy Drug Class Leading to a Substantial Reduction in Diuretic Need?

Despite significant advances in disease modifying therapy in heart failure (HF), diuretics have remained the cornerstone of volume management in all HF phenotypes. Diuretics, alongside their definite acute haemodynamic and symptomatic benefits, also possess many possible deleterious side effects. Moreover, questions remain regarding the prognostic impact of chronic diuretic use. To date, few data exist pertaining to diuretic reduction as a result of individual traditional guideline directed medical therapy in HF with reduced ejection fraction (HFrEF). However, diuretic reduction has been demonstrated with sacubitril/valsartan (angiotensin receptor-neprilysin inhibitor [ARNi]) from the PARADIGM study, as well as, post-marketing reports from our own group and others. Whether the ARNi compound represents the dawn of a new era, where effective therapies will have a more noticeable reduction on diuretic need, remains to be seen. The emergence of sodium glucose transport 2 inhibitors and guanylate cyclase stimulators may further exemplify this issue and potentially extend this benefit to HF patients outside of the HFrEF phenotype. In conclusion, emerging new therapies in HFrEF could reduce the reliance on diuretics in the management of this phenotype of HF. These developments further highlight the clinical importance to continually assess an individual's diuretic requirements through careful volume assessment.

Current Clinical and Pharmacological Approaches to the Prescription of Loop Diuretics in Patients with Chronic Heart Failure

Heart failure (HF) is a growing public health problem with an estimated prevalence of 38 million patients worldwide. Congestion and formation of edema – are typical symptoms of heart failure. Diuretics are the mainstay of therapy in heart failure and are used to relieve congestion and improve exercise tolerance. Also, the administration of diuretics should be considered to reduce the risk of HF hospitalization. Loop diuretics are used by nearly 80% of all chronic HF patients and remain the drugs of choice. Although diuretics are one of the most prescribed classes of drugs, recommendations for their titration scheme for long-term use have not yet been finalized, nor have there been major prospective randomized controlled studies on the effect of diuretics on morbidity and mortality. A Cochrane meta-analysis has shown that in patients with chronic HF, loop and thiazide diuretics might reduce the risk of death and worsening of HF in comparison to placebo and could lead to improved exercise capacity. Guideline recommends the use lowest possible dose of diuretics due to probable electrolyte disturbances, further neurohormonal activation, accelerated kidney function decline, and symptomatic hypotension. Diuretic resistance is associated with an unfavorable prognosis and an increased risk of readmission. There are significant pharmacokinetic differences between the loop diuretics. Compared with furosemide, torasemide has a high bioavailability irrespective of food intake, and carries a longer half‐life and duration of effect; also, the benefits of torasemide are its additional anti-fibrotic and neurohormonal effects. Optimization of diuretic therapy in patients with HF remains a challenge and requires further research, as well as an individual approach to patients, since there is no convincing evidence base.

Current drug therapy for heart failure with reduced ejection fraction

The prevalence of heart failure has been steadily increasing during the past few years, with a further increase predicted in the years to come. Without treatment, the syndrome of heart failure has a very poor prognosis. Advances in drug treatments and the consequent implementation of a guideline-recommended drug therapy have significantly improved the prognosis in heart failure with reduced ejection fraction (HFrEF). Besides angiotensin-converting enzyme (ACE) inhibitors (ACEi) or angiotensin receptor blockers, beta-blockers and diuretics treatment with mineralocorticoid receptor antagonists and ivabradine have become standard in the therapy of symptomatic patients with HFrEF. Recently, the impact of the adequate dosage of ACEi and beta-blockers was emphasized again. Angiotensin receptor-neprilysin inhibition is an auspicious new therapeutic approach and is predicted to play a crucial role in heart failure treatment in the coming years. The role of cardiac glycosides in the modern era of heart failure therapy is the focus of a current randomized controlled trial. Last but not least, potassium binders such as the new substance patiromer might help in overcoming the problem of hyperkalemia, which frequently limits the dosing of vital heart failure drugs. These advances offer optimism for further improvements in the prognosis and quality of life of HFrEF patients.

The New Heart Failure Association Definition of Advanced Heart Failure

The clinical course of heart failure is characterised by progressive worsening of cardiac function and symptoms. Patients progress to a condition where traditional treatment is no longer effective and advanced therapies, such as mechanical circulatory support, heart transplantation and/or palliative care, are needed. This condition is called advanced chronic heart failure. The Heart Failure Association first defined it in 2007 and this definition was updated in 2018. The updated version emphasises the role of comorbidities, including tachyarrhythmias, and the role of heart failure with preserved ejection fraction. Improvements in mechanical circulatory support technology and better disease management programmes are major advances and are radically changing the management of these patients.