The Value of Warning Signs From the WHO 2009 Dengue Classification in Detecting Severe Dengue in Children.

BACKGROUND: World Health Organization proposed 7 warning signs to identify the risk of severe dengue in 2009. This study aimed to evaluate the value of these warning signs in detecting severe dengue in children. MATERIAL AND METHODS: A cross-sectional study was conducted utilizing data of children with clinical dengue infection obtained from medical records between January 2009 and December 2018 in Jakarta. Children with confirmed dengue were analyzed and stratified into 3 age groups: infants less than 1 year old, children 1-14 years and adolescents 15-18 years of age. Positive predictive value, negative predictive value (NPV), sensitivity and specificity of each warning sign present or absent on admission in detecting severe dengue were computed. RESULTS: Six hundred ninety-nine children with clinical dengue infection were enrolled, among whom 614 (87.8%) had confirmed dengue infection, either by antigen or antibody serological tests. Severe dengue occurred in 211/614 (34.4%) cases. In infants, important warning signs on admission to detect or exclude severe dengue were liver enlargement (NPV 80.8%) and clinical fluid accumulation (NPV 75%). In children and adolescents, warning sign with highest NPV (in children 76.6% and in adolescents 91.9%) was increase in hematocrit concurrent with a rapid decrease in platelet count. Other warning signs with high NPV values in children were abdominal pain (72%), vomiting (70%), clinical fluid accumulation (69.3%), and in adolescents' abdominal pain (80.7%), vomiting (75.7%), clinical fluid accumulation (82.7%). NPVs increase with more than 1 warning sign in all age groups. CONCLUSION: In infants, liver enlargement or clinical fluid accumulation are important warning signs for severe dengue, when both are absent, severe dengue is unlikely. In older children and adolescents, an increase in hematocrit with the concurrent rapid decrease in platelet count is most discriminative; followed by the absence of abdominal pain, vomiting or fluid accumulation are unlikely severe dengue.

2023 Focused Update of the 2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: Developed by the task force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC) With the special contribution of the Heart Failure Association (HFA) of the ESC.

Document Reviewers: Rudolf A. de Boer (CPG Review Co-ordinator) (Netherlands), P. Christian Schulze (CPG Review Co-ordinator) (Germany), Elena Arbelo (Spain), Jozef Bartunek (Belgium), Johann Bauersachs (Germany), Michael A. Borger (Germany), Sergio Buccheri (Sweden), Elisabetta Cerbai (Italy), Erwan Donal (France), Frank Edelmann (Germany), Gloria Färber (Germany), Bettina Heidecker (Germany), Borja Ibanez (Spain), Stefan James (Sweden), Lars Køber (Denmark), Konstantinos C. Koskinas (Switzerland), Josep Masip (Spain), John William McEvoy (Ireland), Robert Mentz (United States of America), Borislava Mihaylova (United Kingdom), Jacob Eifer Møller (Denmark), Wilfried Mullens (Belgium), Lis Neubeck (United Kingdom), Jens Cosedis Nielsen (Denmark), Agnes A. Pasquet (Belgium), Piotr Ponikowski (Poland), Eva Prescott (Denmark), Amina Rakisheva (Kazakhstan), Bianca Rocca (Italy), Xavier Rossello (Spain), Leyla Elif Sade (United States of America/Türkiye), Hannah Schaubroeck (Belgium), Elena Tessitore (Switzerland), Mariya Tokmakova (Bulgaria), Peter van der Meer (Netherlands), Isabelle C. Van Gelder (Netherlands), Mattias Van Heetvelde (Belgium), Christiaan Vrints (Belgium), Matthias Wilhelm (Switzerland), Adam Witkowski (Poland), and Katja Zeppenfeld (Netherlands) All experts involved in the development of this Focused Update have submitted declarations of interest. These have been compiled in a report and simultaneously published in a supplementary document to the Focused Update. The report is also available on the ESC website www.escardio.org/guidelines See the European Heart Journal online for supplementary documents that include evidence tables.

Safety of Switching From a Vitamin K Antagonist to a Non-Vitamin K Antagonist Oral Anticoagulant in Frail Older Patients With Atrial Fibrillation: Results of the FRAIL-AF Randomized Controlled Trial.

BACKGROUND: There is ambiguity whether frail patients with atrial fibrillation managed with vitamin K antagonists (VKAs) should be switched to a non-vitamin K oral anticoagulant (NOAC). METHODS: We conducted a pragmatic, multicenter, open-label, randomized controlled superiority trial. Older patients with atrial fibrillation living with frailty (≥75 years of age plus a Groningen Frailty Indicator score ≥3) were randomly assigned to switch from international normalized ratio-guided VKA treatment to an NOAC or to continued VKA treatment. Patients with a glomerular filtration rate <30 mL·min-1·1.73 m-2 or with valvular atrial fibrillation were excluded. Follow-up was 12 months. The cause-specific hazard ratio was calculated for occurrence of the primary outcome that was a major or clinically relevant nonmajor bleeding complication, whichever came first, accounting for death as a competing risk. Analyses followed the intention-to-treat principle. Secondary outcomes included thromboembolic events. RESULTS: Between January 2018 and June 2022, a total of 2621 patients were screened for eligibility and 1330 patients were randomly assigned (mean age 83 years, median Groningen Frailty Indicator score 4). After randomization, 6 patients in the switch-to-NOAC arm and 1 patient in the continue-with-VKA arm were excluded due to the presence of exclusion criteria, leaving 662 patients switched from a VKA to an NOAC and 661 patients continued VKAs in the intention-to-treat population. After 163 primary outcome events (101 in the switch arm, 62 in the continue arm), the trial was stopped for futility according to a prespecified futility analysis. The hazard ratio for our primary outcome was 1.69 (95% CI, 1.23-2.32). The hazard ratio for thromboembolic events was 1.26 (95% CI, 0.60-2.61). CONCLUSIONS: Switching international normalized ratio-guided VKA treatment to an NOAC in frail older patients with atrial fibrillation was associated with more bleeding complications compared with continuing VKA treatment, without an associated reduction in thromboembolic complications. REGISTRATION: URL: https://eudract.ema.europa.eu; Unique identifier: 2017-000393-11. URL: https://eudract.ema.europa.eu; Unique identifier: 6721 (FRAIL-AF study).

Diagnostic yield of a proactive strategy for early detection of cardiovascular disease versus usual care in adults with type 2 diabetes or chronic obstructive pulmonary disease in primary care in the Netherlands (RED-CVD): a multicentre, pragmatic, cluster-randomised, controlled trial.

BACKGROUND: Progressive cardiovascular diseases (eg, heart failure, atrial fibrillation, and coronary artery disease) are often diagnosed late in high-risk individuals with common comorbidities that might mimic or mask symptoms, such as chronic obstructive pulmonary disease (COPD) and type 2 diabetes. We aimed to assess whether a proactive diagnostic strategy consisting of a symptom and risk factor questionnaire and low-cost and accessible tests could increase diagnosis of progressive cardiovascular diseases in patients with COPD or type 2 diabetes in primary care. METHODS: In this multicentre, pragmatic, cluster-randomised, controlled trial (RED-CVD), 25 primary care practices in the Netherlands were randomly assigned to usual care or a proactive diagnostic strategy conducted during routine consultations and consisting of a validated symptom questionnaire, followed by physical examination, N-terminal-pro-B-type natriuretic peptide measurement, and electrocardiography. We included adults (≥18 years) with type 2 diabetes, COPD, or both, who participated in a disease management programme. Patients with an established triple diagnosis of heart failure, atrial fibrillation, and coronary artery disease were excluded. In the case of abnormal findings, further work-up or treatment was done at the discretion of the general practitioner. The primary endpoint was the number of newly diagnosed cases of heart failure, atrial fibrillation, and coronary artery disease, adjudicated by an expert clinical outcome committee using international guidelines, at 1-year follow-up, in the intention-to-treat population. FINDINGS: Between Jan 31, 2019, and Oct 7, 2021, we randomly assigned 25 primary care centres: 11 to usual care and 14 to the intervention. We included patients between June 21, 2019, and Jan 31, 2022. Following exclusion of ineligible patients and those who did not give informed consent, 1216 participants were included: 624 (51%) in the intervention group and 592 (49%) in the usual care group. The mean age of participants was 68·4 years (SD 9·4), 482 (40%) participants were female, and 734 (60%) were male. During 1 year of follow-up, 50 (8%) of 624 participants in the intervention group and 18 (3%) of 592 in the control group were newly diagnosed with heart failure, atrial fibrillation, or coronary artery disease (adjusted odds ratio 2·97 [95% CI 1·66-5·33]). This trial is registered with the Netherlands Trial Registry, NTR7360, and was completed on Jan 31, 2023. INTERPRETATION: An easy-to-use, proactive, diagnostic strategy more than doubled the number of new diagnoses of heart failure, atrial fibrillation, and coronary artery disease in patients with type 2 diabetes or COPD in primary care compared with usual care. Although the effect on patient outcomes remains to be studied, our diagnostic strategy might contribute to improved early detection and timely initiation of treatment in individuals with cardiovascular disease. FUNDING: Dutch Heart Foundation.

Managing the Increasing Burden of Atrial Fibrillation through Integrated Care in Primary Care: A Cost-Effectiveness Analysis.

Introduction: Integrated care for patients with atrial fibrillation (AF) in primary care reduced mortality compared to usual care. We assessed the cost-effectiveness of this approach. Methods: Dutch primary care practices were randomised to provide integrated care for AF patients or usual care. A cost-effectiveness analysis was performed from a societal perspective with a 2-year time horizon to estimate incremental costs and Quality Adjusted Life Years (QALYs). A sensitivity analysis was performed, imputing missing questionnaires for a large group of usual care patients. Results: 522 patients from 15 intervention practices were compared to 425 patients from 11 usual care practices. No effect on QALYs was seen, while mean costs indicated a cost reduction between €865 (95% percentile interval (PI) -€5730 to €3641) and €1343 (95% PI -€6534 to €3109) per patient per 2 years. The cost-effectiveness probability ranged between 36% and 54%. In the sensitivity analysis, this increased to 95%-99%. Discussion: Results should be interpreted with caution due to missing information for a large proportion of usual care patients. Conclusion: The higher costs from extra primary care consultations were likely outweighed by cost reductions for other resources, yet this study doesn't give sufficient clarity on the cost-effectiveness of integrated AF care.

Clinical consequences of off-label reduced dosing of non-vitamin K antagonist oral anticoagulants in patients with atrial fibrillation: a systematic review and meta-analysis.

OBJECTIVE: Postmarketing observational studies report that a substantial percentage of patients with atrial fibrillation (AF) receive a reduced non-vitamin K antagonist oral anticoagulant (NOAC) dose without a clear indication. Recently, increasing evidence has become available to explore the clinical consequences of such off-label reduced dosing (OLRD). This study aims to systematically review and meta-analyse observational studies that report clinical outcomes associated with OLRD of NOACs compared with on-label non-reduced dosing (OLNRD) of NOACs in patients with AF. METHODS AND ANALYSIS: We performed a systematic literature review and meta-analysis of observational studies reporting clinical outcomes in AF patients with OLRD of an NOAC compared with AF patients with OLNRD of an NOAC. Using random effects meta-analyses, we estimated the risk of stroke/thromboembolism, bleeding and all-cause mortality. RESULTS: We included 19 studies with a total of 170 394 NOAC users. In these studies, the percentage of OLRD among patients with an indication for an on-label non-reduced NOAC dose ranged between 9% and 53%. 7 of these 19 studies met the predefined criteria for meta-analysis (n=80 725 patients). The pooled HR associated with OLRD of NOACs was 1.04 (95% CI 0.83 to 1.29; 95% prediction interval (PI) 0.60 to 1.79) for stroke/thromboembolism, 1.10 (95% CI 0.95 to 1.29; 95% PI 0.81 to 1.50) for bleeding and 1.22 (95% CI 0.81 to 1.84; 95% PI 0.55 to 2.70) for all-cause mortality. CONCLUSION: This meta-analysis shows no statistically significant increased risk of stroke/thromboembolism, nor a decreased bleeding risk, nor a difference in risk of all-cause mortality in patients with OLRD of NOACs. Future research may focus on differences between NOACs.

Sex differences in the generalizability of randomized clinical trials in heart failure with reduced ejection fraction.

AIMS: In order to understand how sex differences impact the generalizability of randomized clinical trials (RCTs) in patients with heart failure (HF) and reduced ejection fraction (HFrEF), we sought to compare clinical characteristics and clinical outcomes between RCTs and HF observational registries stratified by sex. METHODS AND RESULTS: Data from two HF registries and five HFrEF RCTs were used to create three subpopulations: one RCT population (n = 16 917; 21.7% females), registry patients eligible for RCT inclusion (n = 26 104; 31.8% females), and registry patients ineligible for RCT inclusion (n = 20 810; 30.2% females). Clinical endpoints included all-cause mortality, cardiovascular mortality, and first HF hospitalization at 1 year. Males and females were equally eligible for trial enrolment (56.9% of females and 55.1% of males in the registries). One-year mortality rates were 5.6%, 14.0%, and 28.6% for females and 6.9%, 10.7%, and 24.6% for males in the RCT, RCT-eligible, and RCT-ineligible groups, respectively. After adjusting for 11 HF prognostic variables, RCT females showed higher survival compared to RCT-eligible females (standardized mortality ratio [SMR] 0.72; 95% confidence interval [CI] 0.62-0.83), while RCT males showed higher adjusted mortality rates compared to RCT-eligible males (SMR 1.16; 95% CI 1.09-1.24). Similar results were also found for cardiovascular mortality (SMR 0.89; 95% CI 0.76-1.03 for females, SMR 1.43; 95% CI 1.33-1.53 for males). CONCLUSION: Generalizability of HFrEF RCTs differed substantially between the sexes, with females having lower trial participation and female trial participants having lower mortality rates compared to similar females in the registries, while males had higher than expected cardiovascular mortality rates in RCTs compared to similar males in registries.

Safety of off-label dose reduction of non-vitamin K antagonist oral anticoagulants in patients with atrial fibrillation.

AIM: To investigate the effects of off-label non-vitamin K oral anticoagulant (NOAC) dose reduction compared with on-label standard dosing in atrial fibrillation (AF) patients in routine care. METHODS: Population-based cohort study using data from the United Kingdom Clinical Practice Research Datalink, comparing adults with non-valvular AF receiving an off-label reduced NOAC dose to patients receiving an on-label standard dose. Outcomes were ischaemic stroke, major/non-major bleeding and mortality. Inverse probability of treatment weighting and inverse probability of censoring weighting on the propensity score were applied to adjust for confounding and informative censoring. RESULTS: Off-label dose reduction occurred in 2466 patients (8.0%), compared with 18 108 (58.5%) on-label standard-dose users. Median age was 80 years (interquartile range [IQR] 73.0-86.0) versus 72 years (IQR 66-78), respectively. Incidence rates were higher in the off-label dose reduction group compared to the on-label standard dose group, for ischaemic stroke (0.94 vs 0.70 per 100 person years), major bleeding (1.48 vs 0.83), non-major bleeding (6.78 vs 6.16) and mortality (10.12 vs 3.72). Adjusted analyses resulted in a hazard ratio of 0.95 (95% confidence interval [CI] 0.57-1.60) for ischaemic stroke, 0.88 (95% CI 0.57-1.35) for major bleeding, 0.81 (95% CI 0.67-0.98) for non-major bleeding and 1.34 (95% CI 1.12-1.61) for mortality. CONCLUSION: In this large population-based study, the hazards for ischaemic stroke and major bleeding were low, and similar in AF patients receiving an off-label reduced NOAC dose compared with on-label standard dose users, while non-major bleeding risk appeared to be lower and mortality risk higher. Caution towards prescribing an off-label reduced NOAC dose is therefore required.

Sex-specific and age-specific incidence of ischaemic heart disease, atrial fibrillation and heart failure in community patients with chronic obstructive pulmonary disease.

OBJECTIVE: To estimate the incidence of ischaemic heart disease, atrial fibrillation and heart failure in community patients with or without chronic obstructive pulmonary disease (COPD). METHODS: For this population-based study, we used primary care data of the Julius General Practitioners' Network. Eligible participants were aged 40-80 years old and contributed data between January 2014 and February 2019. Participants were divided into groups according to COPD status and were followed up for new ischaemic heart disease, atrial fibrillation and/or heart failure. Age-specific and sex-specific incidence and incidence rate ratios were calculated for patients with and without COPD. RESULTS: Mean follow-up was 3.9 years, 6223 patients were included in the COPD group, and 137 028 individuals in the background group without COPD. Incidence rates of all three heart diseases increased with age and were higher in males, independent of presence of COPD. Incidence rate ratios for patients with COPD, adjusted for age and sex, were 1.69 (95% CI 1.49 to 1.92) for ischaemic heart disease, 1.56 (95% CI 1.38 to 1.77) for atrial fibrillation and 2.96 (95% CI 2.58 to 3.40) for heart failure. CONCLUSION: The incidence of all major cardiovascular diseases is higher in patients with COPD, with the highest incidence rate ratio observed for heart failure.

Development and validation of a prediction rule for patients suspected of acute coronary syndrome in primary care: a cross-sectional study.

OBJECTIVE: To develop and validate a symptom-based prediction rule for early recognition of acute coronary syndrome (ACS) in patients with acute chest discomfort who call out-of-hours services for primary care (OHS-PC). DESIGN: Cross-sectional study. A diagnostic prediction rule was developed with multivariable regression analyses. All models were validated with internal-external cross validation within seven OHS-PC locations. Both age and sex were analysed as statistical interaction terms, applying for age non-linear effects. SETTING: Seven OHS-PC in the Netherlands. PARTICIPANTS: 2192 patients who called OHS-PC for acute chest discomfort (pain, pressure, tightness or discomfort) between 2014 and 2017. Backed up recordings of telephone triage conversations were analysed. PRIMARY AND SECONDARY OUTCOMES MEASURES: Diagnosis of ACS retrieved from the patient's medical records in general practice, including hospital specialists discharge letters. Performance of the prediction rules was calculated with the c-statistic and the final model was chosen based on net benefit analyses. RESULTS: Among the 2192 patients who called the OHS-PC with acute chest discomfort, 8.3% females and 15.3% males had an ACS. The final diagnostic model included seven predictors (sex, age, acute onset of chest pain lasting less than 12 hours, a pressing/heavy character of the pain, radiation of the pain, sweating and calling at night). It had an adjusted c-statistic of 0.77 (95% CI 0.74 to 0.79) with good calibration. CONCLUSION: The final prediction model for ACS has good discrimination and calibration and shows promise for replacing the existing telephone triage rules for patients with acute chest discomfort in general practice and OHS-PC. TRIAL REGISTRATION NUMBER: NTR7331.

Preventing heart failure: a position paper of the Heart Failure Association in collaboration with the European Association of Preventive Cardiology.

The heart failure epidemic is growing and its prevention, in order to reduce associated hospital readmission rates and its clinical and economic burden, is a key issue in modern cardiovascular medicine. The present position paper aims to provide practical evidence-based information to support the implementation of effective preventive measures. After reviewing the most common risk factors, an overview of the population attributable risks in different continents is presented, to identify potentially effective opportunities for prevention and to inform preventive strategies. Finally, potential interventions that have been proposed and have been shown to be effective in preventing heart failure are listed.

2021 ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: Developed by the Task Force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC). With the special contribution of the Heart Failure Association (HFA) of the ESC.

Document Reviewers: Rudolf A. de Boer (CPG Review Coordinator) (Netherlands), P. Christian Schulze (CPG Review Coordinator) (Germany), Magdy Abdelhamid (Egypt), Victor Aboyans (France), Stamatis Adamopoulos (Greece), Stefan D. Anker (Germany), Elena Arbelo (Spain), Riccardo Asteggiano (Italy), Johann Bauersachs (Germany), Antoni Bayes-Genis (Spain), Michael A. Borger (Germany), Werner Budts (Belgium), Maja Cikes (Croatia), Kevin Damman (Netherlands), Victoria Delgado (Netherlands), Paul Dendale (Belgium), Polychronis Dilaveris (Greece), Heinz Drexel (Austria), Justin Ezekowitz (Canada), Volkmar Falk (Germany), Laurent Fauchier (France), Gerasimos Filippatos (Greece), Alan Fraser (United Kingdom), Norbert Frey (Germany), Chris P. Gale (United Kingdom), Finn Gustafsson (Denmark), Julie Harris (United Kingdom), Bernard Iung (France), Stefan Janssens (Belgium), Mariell Jessup (United States of America), Aleksandra Konradi (Russia), Dipak Kotecha (United Kingdom), Ekaterini Lambrinou (Cyprus), Patrizio Lancellotti (Belgium), Ulf Landmesser (Germany), Christophe Leclercq (France), Basil S. Lewis (Israel), Francisco Leyva (United Kingdom), AleVs Linhart (Czech Republic), Maja-Lisa Løchen (Norway), Lars H. Lund (Sweden), Donna Mancini (United States of America), Josep Masip (Spain), Davor Milicic (Croatia), Christian Mueller (Switzerland), Holger Nef (Germany), Jens-Cosedis Nielsen (Denmark), Lis Neubeck (United Kingdom), Michel Noutsias (Germany), Steffen E. Petersen (United Kingdom), Anna Sonia Petronio (Italy), Piotr Ponikowski (Poland), Eva Prescott (Denmark), Amina Rakisheva (Kazakhstan), Dimitrios J. Richter (Greece), Evgeny Schlyakhto (Russia), Petar Seferovic (Serbia), Michele Senni (Italy), Marta Sitges (Spain), Miguel Sousa-Uva (Portugal), Carlo G. Tocchetti (Italy), Rhian M. Touyz (United Kingdom), Carsten Tschoepe (Germany), Johannes Waltenberger (Germany/Switzerland) All experts involved in the development of these guidelines have submitted declarations of interest. These have been compiled in a report and published in a supplementary document simultaneously to the guidelines. The report is also available on the ESC website www.escardio.org/guidelines For the Supplementary Data which include background information and detailed discussion of the data that have provided the basis for the guidelines see European Heart Journal online.

Preventing heart failure: a position paper of the Heart Failure Association in collaboration with the European Association of Preventive Cardiology.

The heart failure epidemic is growing and its prevention, in order to reduce associated hospital readmission rates and its clinical and economic burden, is a key issue in modern cardiovascular medicine. The present consensus document aims to provide practical evidence-based information to support the implementation of effective preventive measures. After reviewing the most common risk factors, an overview of the population attributable risks in different continents is presented, to identify potentially effective opportunities for prevention and to inform preventive strategies. Finally, potential interventions that have been proposed and have been shown to be effective in preventing HF are listed.

Missed Acute Coronary Syndrome During Telephone Triage at Out-of-Hours Primary Care: Lessons From A Case-Control Study.

OBJECTIVES: Serious adverse events at out-of-hours services in primary care (OHS-PC) are rare, and the most often concern is missed acute coronary syndrome (ACS). Previous studies on serious adverse events mainly concern root cause analyses, which highlighted errors in the telephone triage process but are hampered by hindsight bias. This study compared the recorded triage calls of patients with chest discomfort contacting the OHS-PC in whom an ACS was missed (cases), with triage calls involving matched controls with chest discomfort but without a missed ACS (controls), with the aim to assess the predictors of missed ACS. METHODS: A case-control study with data from 2013 to 2017 of 9 OHS-PC in the Netherlands. The cases were matched 1:8 with controls based on age and sex. Clinical, patient, and call characteristics were univariably assessed, and general practitioner experts evaluated the triage while blinded to the final diagnosis or the case-control status. RESULTS: Fifteen missed ACS calls and 120 matched control calls were included. Cases used less cardiovascular medication (38.5% versus 64.1%, P = 0.05) and more often experienced pain other than retrosternal chest pain (63.3% versus 24.7%, P = 0.02) compared with controls. Consultation of the supervising general practitioner (86.7% versus 49.2%, P = 0.02) occurred more often in cases than in controls. Experts rated the triage of cases more often as "poor" (33.3% versus 10.9%, P = 0.001) and "unsafe" (73.3% versus 22.5%, P < 0.001) compared with controls. CONCLUSIONS: To facilitate learning from serious adverse events in the future, these should also be bundled and carefully assessed without hindsight bias and within the context of "normal" clinical practice.

Generalizability of randomized controlled trials in heart failure with reduced ejection fraction.

BACKGROUND: Heart failure (HF) trials have stringent inclusion and exclusion criteria, but limited data exist regarding generalizability of trials. We compared patient characteristics and outcomes between patients with HF and reduced ejection fraction (HFrEF) in trials and observational registries. METHODS AND RESULTS: Individual patient data for 16 922 patients from five randomized clinical trials and 46 914 patients from two HF registries were included. The registry patients were categorized into trial-eligible and non-eligible groups using the most commonly used inclusion and exclusion criteria. A total of 26 104 (56%) registry patients fulfilled the eligibility criteria. Unadjusted all-cause mortality rates at 1 year were lowest in the trial population (7%), followed by trial-eligible patients (12%) and trial-non-eligible registry patients (26%). After adjustment for age and sex, all-cause mortality rates were similar between trial participants and trial-eligible registry patients [standardized mortality ratio (SMR) 0.97; 95% confidence interval (CI) 0.92-1.03] but cardiovascular mortality was higher in trial participants (SMR 1.19; 1.12-1.27). After full case-mix adjustment, the SMR for cardiovascular mortality remained higher in the trials at 1.28 (1.20-1.37) compared to RCT-eligible registry patients. CONCLUSION: In contemporary HF registries, over half of HFrEF patients would have been eligible for trial enrolment. Crude clinical event rates were lower in the trials, but, after adjustment for case-mix, trial participants had similar rates of survival as registries. Despite this, they had about 30% higher cardiovascular mortality rates. Age and sex were the main drivers of differences in clinical outcomes between HF trials and observational HF registries.