Right ventricular dysfunction in chronic heart failure: clinical laboratory and echocardiographic characteristics. (the RIVED-CHF registry).

BACKGROUND: Right ventricular dysfunction (RVD) and pulmonary hypertension have been recognized as two important prognostic features in patients with left side heart failure. Current literature does not distinguish between right heart failure (RHF) and RVD, and the two terms are used indiscriminately to describe pulmonary hypertension and RVD as well as clinical sign of RHF. Therefore, the right ventricle (RV) adaptation across the whole spectrum of left ventricular ejection fraction (LVEF) values has been poorly investigated. METHODS: This is a multicenter observational prospective study endorsed by the Italian Society of Cardiology aiming to analyze the concordance between the signs and symptoms of RHF and echocardiographic features of RVD. The protocol will assess patients affected by chronic heart failure in stable condition regardless of the LVEF threshold by clinical, laboratory, and detailed echocardiographic study. During the follow-up period, patients will be observed by direct check-up visit and/or virtual visits every 6 months for a mean period of 3 years. All clinical laboratory and echocardiographic data will be recorded in a web platform system accessible for all centers included in the study. RESULTS: The main study goals are: to investigate the concordance and discordance between clinical signs of RHF and RVD measured by ultrasonographic examination; to evaluate prognostic impact (in terms of cardiovascular mortality and heart failure hospitalization) of RVD and RHF during a mean follow-up period of 3 years; to investigate the prevalence of different right ventricular maladaptation (isolated right ventricular dilatation, isolated pulmonary hypertension, combined pattern) and the related prognostic impact. CONCLUSIONS: With this protocol, we would investigate the three main RVD patterns according to heart failure types and stages; we would clarify different RVD and pulmonary hypertension severity according to the heart failure types. Additionally, by a serial multiparametric analysis of RV, we would provide a better definition of RVD stage and how much is it related with clinical signs of RHF (ClinicalTrials.gov Identifier: NCT06002321).

Sharing the multidisciplinary clinical approach to peri- and postmenopausal women: A Delphi consensus among Italian gynecologists, endocrinologists, and cardiologists for an integrated and optimal approach to clinical practice.

OBJECTIVE: The critical phase of perimenopausal period is marked by a reduction in estrogen levels, leading to various clinical issues (vasomotor and neurodegenerative symptoms, increased osteoporosis risk and cardiovascular risk). These complex clinical scenarios pose challenges to clinicians in providing the right support for diagnosis and treatment. A group of Italian cardiologists, endocrinologists, and gynecologists conducted a survey among expert colleagues to assess consensus on controversial issues and best practices for screening and treating peri- and postmenopausal women. METHODS: The Delphi methodology was used to analyze responses from a qualitative expert panel comprising 25 cardiologists, 25 endocrinologists, and 25 gynecologists, selected nationwide. Two consecutive questionnaires were proposed between February and May 2023. Agreement among experts was assessed following the Delphi method as developed by the RAND Corporation. RESULTS: The results of this Delphi Consensus have been shared by the leading scientific societies: Italian Society of Cardiology, Italian Society of Endocrinology, Italian Society of Gynecology and Obstetrics, and Italian Hospital Obstetricians Gynecologists Association. CONCLUSIONS: The experts highlighted comorbidities and hormone deprivation as crucial clinical problems to be evaluated in perimenopausal women, requiring investigation from cardiovascular and endocrinologic perspectives to assess cardiovascular risk, involving the use of BMI, standard blood samples, endocrine-metabolic tests, and lifestyle assessment, particularly in women with higher cardiovascular and metabolic risks candidates for hormone replacement therapy (HRT). The experts also agreed on the benefits of HRT in improving lipid metabolism and reducing insulin resistance, thereby mitigating the metabolic risks associated with menopause. However, this therapy should be tailored considering individual women's comorbidities and thrombotic risk.

What about chronotropic incompetence in heart failure with mildly reduced ejection fraction? Clinical and prognostic implications from the Metabolic Exercise combined with Cardiac and Kidney Indexes score dataset.

AIMS: Chronotropic incompetence (CI) is a strong predictor of outcome in heart failure with reduced ejection fraction, however no data on its clinical and prognostic impacts in heart failure with mildly reduced ejection fraction (HFmrEF) are available. Therefore, the study aims to investigate, in a large multicentre HFmrEF cohort, the prevalence of CI as well as its relationship with exercise capacity and its prognostic role over the cardiopulmonary exercise testing (CPET) parameters. METHODS AND RESULTS: Within the Metabolic Exercise combined with Cardiac and Kidney Indexes (MECKI) database, we analysed data of 864 HFmrEF out of 1164 stable outpatients who performed a maximal CPET at the cycle ergometer and who had no significant rhythm disorders or comorbidities. The primary study endpoint was cardiovascular (CV) death. All-cause death was also explored. Chronotropic incompetence prevalence differed depending on the method (peak heart rate, pHR% vs. pHR reserve, pHRR%) and the cut-off adopted (pHR% from ≤75% to ≤60% and pHRR% ≤ 65% to ≤50%), ranging from 11% to 62%. A total of 84 (9.7%) CV deaths were collected, with 39 (4.5%) occurring within 5 years. At multivariate analysis, both pHR% [hazard ratio 0.97 (0.95-0.99), P < 0.05] and pHRR% [hazard ratio 0.977 (0.961-0.993), P < 0.01] were associated with the primary endpoint. A pHR% ≤ 75% and a pHRR% ≤ 50% represented the most accurate cut-off values in predicting the outcome. CONCLUSION: The study suggests an association between blunted exercise-HR response, functional capacity, and CV death risk among patients with HFmrEF. Whether the CI presence might be adopted in daily HFmrEF management needs to be addressed in larger prospective studies.

Chronotropic incompetence is an easy-to-obtain additive parameter for cardiovascular death risk stratification in heart failure with mildly reduced ejection fraction (HFmrEF). Peak heart rate and peak heart rate reserve are associated with exercise capacity in HFmrEF. Peak heart rate and peak heart rate reserve are associated with cardiovascular death in HFmrEF.

Effects of sacubitril/valsartan on exercise capacity: a prognostic improvement that starts during uptitration.

PURPOSE: Sacubitril/valsartan is a mainstay of the treatment of heart failure with reduced ejection fraction (HFrEF); however, its effects on exercise performance yielded conflicting results. Aim of our study was to evaluate the impact of sacubitril/valsartan on exercise parameters and echocardiographic and biomarker changes at different drug doses. METHODS: We prospectively enrolled consecutive HFrEF outpatients eligible to start sacubitril/valsartan. Patients underwent clinical assessment, cardiopulmonary exercise test (CPET), blood sampling, echocardiography, and completed the Kansas City Cardiomyopathy Questionnaire (KCCQ-12). Sacubitril/valsartan was introduced at 24/26 mg b.i.d. dose and progressively uptitrated in a standard monthly-based fashion to 97/103 mg b.i.d. or maximum tolerated dose. Study procedures were repeated at each titration visit and 6 months after reaching the maximum tolerated dose. RESULTS: Ninety-six patients completed the study, 73 (75%) reached maximum sacubitril/valsartan dose. We observed a significant improvement in functional capacity across all study steps: oxygen intake increased, at peak exercise (from 15.6 ± 4.5 to 16.5 ± 4.9 mL/min/kg; p trend = 0.001), while minute ventilation/carbon dioxide production relationship reduced in patients with an abnormal value at baseline. Sacubitril/valsartan induced positive left ventricle reverse remodeling (EF from 31 ± 5 to 37 ± 8%; p trend < 0.001), while NT-proBNP reduced from 1179 [610-2757] to 780 [372-1344] pg/ml (p trend < 0.0001). NYHA functional class and the subjective perception of limitation in daily life at KCCQ-12 significantly improved. The Metabolic Exercise Cardiac Kidney Index (MECKI) score progressively improved from 4.35 [2.42-7.71] to 2.35% [1.24-4.96], p = 0.003. CONCLUSIONS: A holistic and progressive HF improvement was observed with sacubitril/valsartan in parallel with quality of life. Likewise, a prognostic enhancement was observed.

The gray areas of oral anticoagulation for prevention of thromboembolic events in atrial fibrillation patients.

Thromboembolic events (TEE) associated with atrial fibrillation (AF) are highly recurrent and usually severe, causing permanent disability or, even, death. Previous data consistently showed significantly lower TEE in anticoagulated patients. While warfarin, a vitamin K antagonist, is still used worldwide, direct-acting oral anticoagulants (DOACs) have shown noninferiority to warfarin in the prevention of TEE, and represent, to date, the preferred treatment. DOACs present favorable pharmacokinetic, safety and efficacy profiles, especially among vulnerable patients including the elderly, those with renal dysfunction or previous TEE. Yet, regarding specific settings of AF patients it is unclear whether oral anticoagulation therapy is beneficial, or otherwise it is the maintenance of sinus rhythm, mostly achieved through a catheter ablation-based rhythm control strategy, that prevents the causal complications linked to AF. While it is known that low-risk patients [CHA2DS2-VASc 0 (males), or score of 1 (females)] present low ischemic stroke or mortality rates (<1%/year), it remains unclear whether they need any prophylaxis. Furthermore, the appropriate anticoagulation regimen for those individuals requiring cardioversion, either pharmacologic or electric, as well as peri-procedural anticoagulation in patients undergoing trans-catheter ablation that nowadays encompasses different energies, are still a matter of debate. In addition, AF concomitant with other clinical conditions is discussed and, lastly, the choice of prescribing anticoagulation to asymptomatic patients diagnosed with subclinical AF at either wearable or implanted devices. The aim of this review will be to provide an update on current strategies in the above-mentioned settings, and to suggest possible therapeutic options, finally focusing on AF-related cognitive decline.

Lipid-lowering therapy in patients with coronary artery disease undergoing percutaneous coronary interventions in Italy: an expert opinion paper of Interventional Cardiology Working Group of Italian Society of Cardiology.

After percutaneous coronary interventions (PCIs), patients remain at high risk of developing recurrent cardiovascular events. Despite advances in interventional cardiology, the correct management of residual low-density lipoprotein cholesterol (LDL-C) risk continues to be crucial for improving long-term outcomes after PCI. However, several observational studies have demonstrated suboptimal LDL-C control, poor adherence to statin therapy, and underutilization of high-intensity statins, ezetimibe, and proprotein convertase subtilisin/kexin type 9 inhibitors in real-world clinical practice despite a strong endorsement from international guidelines. Recent studies have shown that early intensive lipid-lowering therapy stabilizes atheromatous plaque and increases fibrous cap thickness in patients with acute coronary syndrome. This finding emphasizes the importance of achieving therapeutic targets by establishing an effective treatment as early as possible. The aim of this expert opinion paper of the Interventional Cardiology Working Group of the Italian Society of Cardiology is to discuss the management of lipid-lowering therapy in patients undergoing PCIs according to Italian reimbursement policies and regulations, with a particular focus on the discharge phase.

How cardiologists can manage excess body weight and related cardiovascular risk. An expert opinion.

Obesity is an important independent cardiovascular (CV) risk factor and a chronic inflammatory disease related to the development of insulin resistance, type 2 diabetes, dyslipidaemia, coronary artery disease, hypertension, heart failure, atrial fibrillation and obstructive sleep apnoea. Body Mass Index (BMI) values >27 kg/m2 are associated with an exponential increase in the risk for Major Adverse Cardiac Events (MACE). On the other hand, weight reduction can significantly reduce metabolic, CV and oncological risk. Orlistat, bupropion/naltrexone, liraglutide and semaglutide, combined with lifestyle changes, have proven to be effective in weight loss; the last two have been tested in randomized clinical trials (RCTs) with CV outcomes only in diabetic patients, and not in obese patients. To fill a fundamental gap of knowledge, the SELECT trial on patients with obesity and CV disease treated with semaglutide is ongoing, aiming at MACE as the primary endpoint. The battle against the social and clinical stigma towards obesity must be counteracted by promoting an awareness that elevates obesity to a complex chronic disease. Several actions should be implemented to improve the management of obesity, and cardiologists have a key role for achieving a global approach to patients with excess weight also through the correct implementation of available treatment strategies.

Innovations in medical therapy of heart failure with reduced ejection fraction.

Heart failure with reduced ejection fraction (HFrEF) is a pathological condition still characterized by high rates of mortality and disease exacerbation frequently leading to hospitalization, thus there is a continuous need for pharmacological treatments impacting on disease stability and long-term prognosis. Moreover, the phenotype of heart failure patients is continuously changing over time, and the development of new heart failure drugs is crucial to promote a personalized and targeted approach. In recent years, several therapeutic innovations have emerged in the landscape of acute and chronic HFrEF, largely changing and improving our approach to the disease. Various studies on new drugs and experimental therapeutic approaches are ongoing. The present review discusses the latest data on both recently approved drugs and developing therapeutic targets, in order to provide a critical overview for an informed and optimal approach to such a complex disease.

Clinical application of CMR in cardiomyopathies: evolving concepts and techniques : A position paper of myocardial and pericardial diseases and cardiac magnetic resonance working groups of Italian society of cardiology.

Cardiac magnetic resonance (CMR) has become an essential tool for the evaluation of patients affected or at risk of developing cardiomyopathies (CMPs). In fact, CMR not only provides precise data on cardiac volumes, wall thickness, mass and systolic function but it also a non-invasive characterization of myocardial tissue, thus helping the early diagnosis and the precise phenotyping of the different CMPs, which is essential for early and individualized treatment of patients. Furthermore, several CMR characteristics, such as the presence of extensive LGE or abnormal mapping values, are emerging as prognostic markers, therefore helping to define patients' risk. Lastly new experimental CMR techniques are under investigation and might contribute to widen our knowledge in the field of CMPs. In this perspective, CMR appears an essential tool to be systematically applied in the diagnostic and prognostic work-up of CMPs in clinical practice. This review provides a deep overview of clinical applicability of standard and emerging CMR techniques in the management of CMPs.

Does moderate hyperkalemia influence survival in HF? Insights from the MECKI score data base.

BACKGROUND: The prognostic role of moderate hyperkalemia in reduced ejection fraction (HFrEF) patients is still controversial. Despite this, it affects the use of renin-angiotensin-aldosterone system inhibitors (RAASi) with therapy down-titration or discontinuation. OBJECTIVES: Aim of the study was to assess the prognostic impact of moderate hyperkalemia in chronic HFrEF optimally treated patients. METHODS AND RESULTS: We retrospectively analyzed MECKI (Metabolic Exercise test data combined with Cardiac and Kidney Indexes) database, with median follow-up of 4.2 [IQR 1.9-7.5] years. Data on K+ levels were available in 7087 cases. Patients with K+ plasma level ≥ 5.6 mEq/L and < 4 mEq/L were excluded. Remaining patients were categorized into normal >4 and < 5 mEq/L (n = 4826, 68%) and moderately high ≥5.0 and ≤ 5.5 mEq/L (n = 496, 7%) K+. Then patients were matched by propensity score in 484 couplets of patients. MECKI score value was 7% [IQR 3.1-14.1%] and 7.3% [IQR 3.4-15%] (p = 0.678) in patients with normal and moderately high K+ values while cardiovascular mortality events at two years follow-up were 41 (4.2%) and 33 (3.4%) (p = 0.333) in each group respectively. CONCLUSIONS: Moderate hyperkalemia does not influence patients' outcome in a large cohort of ambulatory HFrEF patients.

Cardiorenal syndrome: Pathophysiology as a key to the therapeutic approach in an under-diagnosed disease.

Cardiorenal syndrome is a clinical condition that impacts both the heart and the kidneys. One organ's chronic or acute impairment can lead to the other's chronic or acute dysregulation. The cardiorenal syndrome has been grouped into five subcategories that describe the etiology, pathophysiology, duration, and pattern of cardiac and renal dysfunction. This classification reflects the large spectrum of interrelated dysfunctions and underlines the bidirectional nature of heart-kidney interactions. However, more evidence is needed to apply these early findings in medical practice. Understanding the relationship between these two organs during each organ's impairment has significant clinical implications that are relevant for therapy in both chronic and acute conditions. The epidemiology, definition, classification, pathophysiology, therapy, and outcome of each form of cardiorenal syndrome are all examined in this review.

[Italian Society of Cardiology-Italian Society of Nephrology Consensus document: The cardio-renal interaction in the prevention and treatment of cardiovascular diseases - Part I: From cardiovascular risk factors to the mechanisms of cardio-renal syndrome]. / Documento di consenso Società Italiana di Cardiologia- Società Italiana di Nefrologia: Ruolo dell'asse cardio-renale nella prevenzione e trattamento delle patologie cardiovascolari ­ Parte I: Dai fattori di rischio cardiovascolare ai meccanismi di danno cardio-renale.

Chronic kidney disease (CKD) and cardiovascular (CV) disease are highly prevalent conditions in the general population and are strictly connected to each other with a bidirectional interaction. In patients affected by CKD, the leading cause of morbidity and mortality is represented by CV disease, since CKD promotes the atherosclerotic process increasing inflammation, and modifying lipid and bone mineral metabolism. On the other side, a strict relationship exists between CKD and CV risk factors, which are prevalent in nephropathic patients and impose a stringent assessment of the risk of CV events in this population together with an optimized pharmacological approach, complicated by the coexistence of the two pathological conditions. The first part of this consensus document focuses on the mechanisms of cardio-renal damage and on the impact, as well as the management, of the main CV risk factors in the context of CKD.

Revisiting a Prognosticating Algorithm from Cardiopulmonary Exercise Testing in Chronic Heart Failure (from the MECKI Score Population).

Cardiopulmonary exercise testing is a prognostic tool in heart failure with reduced left ventricular ejection fraction (HFrEF). Prognosticating algorithms have been proposed, but none has been validated. In 2017, a predictive algorithm, based on peak oxygen consumption (VO2), ventilatory response to exercise (ventilation [VE] carbon dioxide production [VCO2], the VE/VCO2 slope), exertional oscillatory ventilation (EOV), and peak respiratory exchange ratio, was recommended, according treatment with ß blockers: patients with HFrEF registered in the metabolic exercise test data combined with cardiac and kidney indexes (MECKIs) database were used to validated this algorithm. According to the inclusion/exclusion criteria, 4,683 MECKI patients with HFrEF were enrolled. At 3 years follow-up, the end point was cardiovascular death and urgent heart transplantation (cardiovascular events [CV]). CV events occurred in 25% in patients without ß blockers, whereas those with ß-blockers had 11% (p <0.0001). In patients without ß blockers, 36%, 24%, and 7% CV events were observed in those with peak VO2 ≤10, with peak VO2 >10 <18, and with peak VO2 ≥18 ml/kg/min (p = 0.0001), respectively; in MECKI patients with peak VO2 ≤10 and patients with intermediate exercise capacity, a peak respiratory exchange ratio (≥1.15) and VE/VCO2 slope (≥35) were diriment, respectively (p = 0.0001). EOV, when occurred, increased risk. In MECKI patients on ß blockers, 29%, 17%, and 8% CV events were noticed in those with a peak VO2 ≤8, with peak VO2 = 8 to 12, and patients with peak VO2 ≥12 ml/kg/min, respectively (p = 0.0000); when EOV was monitored an increment of risk was witnessed. In conclusion, the outcome of this algorithm was confirmed with the MECKI cohort.

Perspectives in noninvasive imaging for chronic coronary syndromes.

Both the latest European guidelines on chronic coronary syndromes and the American guidelines on chest pain have underlined the importance of noninvasive imaging to select patients to be referred to invasive angiography. Nevertheless, although coronary stenosis has long been considered the main determinant of inducible ischemia and symptoms, growing evidence has demonstrated the importance of other underlying mechanisms (e.g., vasospasm, microvascular disease, energetic inefficiency). The search for a pathophysiology-driven treatment of these patients has therefore emerged as an important objective of multimodality imaging, integrating "anatomical" and "functional" information. We here provide an up-to-date guide for the choice and the interpretation of the currently available noninvasive anatomical and/or functional tests, focusing on emerging techniques (e.g., coronary flow velocity reserve, stress-cardiac magnetic resonance, hybrid imaging, functional-coronary computed tomography angiography, etc.), which could provide deeper pathophysiological insights to refine diagnostic and therapeutic pathways in the next future.

[From statin revolution to gene silencing therapy: 50 years of evolution in the treatment of hypercholesterolemia]. / Dalla rivoluzione delle statine alla terapia di silenziamento genico: 50 anni di evoluzione nella terapia dell'ipercolesterolemia.

The last 50 years have experienced a rapid evolution in the development of lipid-lowering agents to reduce low-density lipoprotein cholesterol levels. This significant advance in medicine has not occurred without debate. Whether lowering blood cholesterol levels was beneficial has remained one of the most controversial issues during the past 50 years. The discovery of statins was the revolution that made it possible to delay and stop the progression of the atherosclerotic process resulting in improved health and longevity for millions of people. To date, statins remain the drugs of choice for the treatment of hypercholesterolemia. Despite their use, the risk of cardiovascular events persists. Therefore, the use of non-statin drugs, such as ezetimibe or PCSK9 inhibitors, in combination with statins has been shown to further reduce the risk of cardiovascular events. This review aims to summarize the advances in the field of lipid-lowering therapies over the past 50 years, focusing on advances in the development of drug therapies up to and including gene silencing or gene editing treatments that are expected in the near future.

[Italian Society of Cardiology (SIC) Expert consensus document: Post-acute cardiovascular sequelae of SARS-CoV-2 infection]. / Expert consensus document della Società Italiana di Cardiologia (SIC): Sequele cardiovascolari post-acute dell'infezione da SARS-CoV-2.

Although the clinical course of COVID-19 in its acute phase is now delineated, less known is its late phase characterized by a heterogeneous series of sequelae affecting various organs and systems, including the cardiovascular system, which continue after the acute episode or arise after their resolution. This syndrome, now referred with the new acronym "PASC" (post-acute sequelae of SARS-CoV-2 infection) has been formally recognized by various scientific societies and international organizations that have proposed various definitions. The World Health Organization defines PASC, distinguishing it from "ongoing symptomatic COVID-19", as a condition that arises few weeks after infection, persists at least 8 weeks, and cannot be explained by alternative diagnoses.There are multiple mechanisms responsible for PASC: inflammation, immune activation, viral persistence, activation of latent viruses, endothelial dysfunction, impaired response to exercise, and profound cardiac deconditioning following viral infection. The key symptoms of PASC are palpitations, effort dyspnea, chest pain, exercise intolerance, and postural orthostatic tachycardia syndrome.For PASC treatment, it may be useful to take salt and fluid loading, to reduce symptoms such as tachycardia, palpitations, and/or orthostatic hypotension, or in some subjects the use of drugs such as beta-blockers, non-dihydropyridine calcium channel blockers, ivabradine, and fludrocortisone.Finally, in PASC a gradual resumption of physical activity is recommended, starting with recumbent or semi-recumbent exercise, such as cycling, swimming, or rowing, and then moving on to exercise in an upright position such as running when the ability to stand improves without dyspnea appearance. Exercise duration should also be short initially (5 to 10 min per day), with gradual increases as functional capacity improves.

[2022 Update on myocarditis and pericarditis following COVID-19 vaccination. Expert Opinion of the Italian Society of Cardiology]. / Update 2022 dell'Expert Opinion della Società Italiana di Cardiologia su miocarditi, pericarditi e vaccini contro il COVID-19.

Vaccine-associated myocarditis and pericarditis usually develop within 14 days of COVID-19 vaccination, are exceptionally rare, manifest with mild clinical pictures and are commonly characterized by a favorable evolution. Young men inoculated with two doses of an mRNA vaccine are the subgroup at higher risk. Recent epidemiological studies evaluated the incidence and risk of vaccine-associated myocarditis and pericarditis among men and women, in different ranges of age and specific types of vaccines. Long-term population analyses demonstrated that the cardiovascular risk conferred by COVID-19 extends beyond the acute phase, representing the rationale for implementing prevention strategies for SARS-CoV-2 infection, monitoring specific populations at higher risk and pursuing the completion of the vaccination campaign. This document provides an update on the most recent scientific evidence and critical interpretation of available data in constant evolution towards personalized strategies of immunization.

Pick Your Threshold: A Comparison Among Different Methods of Anaerobic Threshold Evaluation in Heart Failure Prognostic Assessment.

BACKGROUND: In clinical practice, anaerobic threshold (AT) is used to guide training and rehabilitation programs, to define risk of major thoracic or abdominal surgery, and to assess prognosis in heart failure (HF). AT of oxygen uptake (V.O2; V.O2AT) has been reported as an absolute value (V.O2ATabs), as a percentage of predicted peak V.O2 (V.O2AT%peak_pred), or as a percentage of observed peak V.O2 (V.O2AT%peak_obs). A direct comparison of the prognostic power among these different ways to report AT is missing. RESEARCH QUESTION: What is the prognostic power of these different ways to report AT? STUDY DESIGN AND METHODS: In this observational cohort study, we screened data of 7,746 patients with HF with a history of reduced ejection fraction (< 40%) recruited between 1998 and 2020 and enrolled in the Metabolic Exercise Combined With Cardiac and Kidney Indexes register. All patients underwent a maximum cardiopulmonary exercise test, executed using a ramp protocol on an electronically braked cycle ergometer. RESULTS: This study considered 6,157 patients with HF with identified AT. Follow-up was median, 4.2 years (25th-75th percentiles, 1.9-5.0 years). Both V.O2ATabs (mean ± SD, 823 ± 305 mL/min) and V.O2AT%peak_pred (mean ± SD, 39.6 ± 13.9%), but not V.O2AT%peak_obs (mean ± SD, 69.2 ± 17.7%), well stratified the population regarding prognosis (composite end point: cardiovascular death, urgent heart transplant, or left ventricular assist device). Comparing area under the receiver operating characteristic curve (AUC) values, V.O2ATabs (0.680) and V.O2AT%peak_pred (0.688) performed similarly, whereas V.O2AT%peak_obs (0.538) was significantly weaker (P < .001). Moreover, the V.O2AT%peak_pred AUC value was the only one performing as well as the AUC based on peak V.O2 (0.710), with an even a higher AUC (0.637 vs 0.618, respectively) in the group with severe HF (peak V.O2 < 12 mL/min/kg). Finally, the combination of V.O2AT%peak_pred with peak V.O2 and V. per CO2 production shows the highest prognostic power. INTERPRETATION: In HF, V.O2AT%peak_pred is the best way to report V.O2 at AT in relationship to prognosis, with a prognostic power comparable to that of peak V.O2 and, remarkably, in patients with severe HF.