Cause-specific death in heart failure across the ejection fraction spectrum: A comprehensive assessment of over 100 000 patients in the Swedish Heart Failure Registry.

AIM: To assess cause-specific death in patients with heart failure with preserved, mildly reduced, and reduced ejection fraction (HFpEF, HFmrEF, and HFrEF). METHODS AND RESULTS: Data were analysed from the Swedish Heart Failure Registry (SwedeHF) and the National Patient Register of patients enrolled in SwedeHF 2000-2021. Cox proportional hazards regression models were performed and adjusted for age, sex and time period. Among 100 584 patients (23% HFpEF, 23% HFmrEF, 53% HFrEF), median age (interquartile range) was 75 (66-82) and 36% were female. Of those who died within 5 years, most deaths were ascribed to cardiovascular (CV) causes across all ejection fraction (EF) categories. Within 5 years, HFpEF had higher adjusted risk of non-CV death (hazard ratio [HR] 1.33, 95% confidence interval [CI] 1.28-1.38, p < 0.001) and lower adjusted risk of CV death (HR 0.85, 95% CI 0.82-0.88, p < 0.001) compared to HFrEF. Ischaemic heart disease (IHD) and cancer were the most common causes of CV and non-CV death regardless of EF category. The incidence rate of CV death due to IHD was highest in HFrEF while incidence rates of CV death due to pulmonary vascular disease, stroke, valvular heart disease and atrial fibrillation increased with increasing EF. The incidence rates of non-CV deaths due to cancer, respiratory disease, and infections increased with increasing EF. CONCLUSION: Cardiovascular death was more common than non-CV death across all EF categories although the risk of non-CV death within 5 years was higher with increasing EF. IHD and cancer were the most common causes of CV and non-CV deaths, respectively, regardless of EF category.

Glucagon-like peptide-1 receptor agonists use and associations with outcomes in heart failure and type 2 diabetes. Data from the Swedish Heart Failure and Swedish National Diabetes Registries.

AIMS: To assess use and associations with outcomes of glucagon-like peptide-1 receptor agonists (GLP-1 RA) in a real-world population with heart failure (HF) and type 2 diabetes (T2DM). METHODS AND RESULTS: The Swedish HF Registry was linked with the National Diabetes Registry and other national registries. Independent predictors of GLP-1 RA use were assessed by multivariable logistic regressions, and associations with outcomes by Cox regressions in a 1:1 propensity score-matched cohort. Of 8188 patients enrolled in 2017-2021, 9% received a GLP-1 RA. Independent predictors of GLP-1 RA use were age<75, worse glycaemic control, impaired renal function, obesity and reduced ejection fraction (EF). GLP-1 RA use was not significantly associated with a composite of HF hospitalization (HHF) or cardiovascular (CV) death regardless of EF, but was associated with lower risk of major adverse CV events (CV death, non-fatal stroke/transient ischemic attack or myocardial infarction), CV and all-cause death. In patients with body mass index≥30 kg/m2, GLP-1 RA use was also associated with lower risk of HHF/CV death and HHF alone. CONCLUSIONS: In patients with HF and T2DM, GLP-1 RA use was independently associated with more severe T2DM, reduced EF and obesity, and was not associated with a higher risk of HHF/CV death but with longer survival and less major CV adverse events. An association with lower HHF/CV death and HHF was observed in obese patients. Our findings provide new insights into GLP-1 RA use and its safety in HF and T2DM.

Epigenetic modulators link mitochondrial redox homeostasis to cardiac function in a sex-dependent manner.

While excessive production of reactive oxygen species (ROS) is a characteristic hallmark of numerous diseases, clinical approaches that ameliorate oxidative stress have been unsuccessful. Here, utilizing multi-omics, we demonstrate that in cardiomyocytes, mitochondrial isocitrate dehydrogenase (IDH2) constitutes a major antioxidative defense mechanism. Paradoxically reduced expression of IDH2 associated with ventricular eccentric hypertrophy is counterbalanced by an increase in the enzyme activity. We unveil redox-dependent sex dimorphism, and extensive mutual regulation of the antioxidative activities of IDH2 and NRF2 by a feedforward network that involves 2-oxoglutarate and L-2-hydroxyglutarate and mediated in part through unconventional hydroxy-methylation of cytosine residues present in introns. Consequently, conditional targeting of ROS in a murine model of heart failure improves cardiac function in sex- and phenotype-dependent manners. Together, these insights may explain why previous attempts to treat heart failure with antioxidants have been unsuccessful and open new approaches to personalizing and, thereby, improving such treatment.

Impact of coronary microvascular dysfunction in heart failure with preserved ejection fraction: a meta-analysis.

AIMS: Several mechanisms have been identified in the aetiopathogenesis of heart failure with preserved ejection fraction (HFpEF). Among these, coronary microvascular dysfunction (CMD) may play a key pathophysiological role. We performed a systematic review and meta-analysis to investigate the prevalence, echocardiographic correlates, and prognostic implications of CMD in patients with HFpEF. METHODS AND RESULTS: A systematic search for articles up to 1 May 2023 was performed. The primary aim was to assess the prevalence of CMD. Secondary aims were to compare key echocardiographic parameters (E/e' ratio, left atrial volume index [LAVi], and left ventricular mass index [LVMi]), clinical outcomes [death and hospitalization for heart failure (HF)], and prevalence of atrial fibrillation (AF) between patients with and without CMD. Meta-regressions according to baseline patient characteristics and study features were performed to explore potential heterogeneity sources. We identified 14 observational studies, enrolling 1138 patients with HFpEF. The overall prevalence of CMD was 58%. Compared with patients without CMD, patients with HFpEF and CMD had larger LAVi [mean difference (MD) 3.85 confidence interval (CI) 1.19-6.5, P < 0.01)], higher E/e' ratio (MD 2.76 CI 1.54-3.97; P < 0.01), higher prevalence of AF (odds ratio 1.61 CI 1.04-2.48, P = 0.03) and higher risk of death or hospitalization for HF [hazard ratio 3.19, CI 1.04-9.57, P = 0.04]. CONCLUSIONS: CMD is present in little more than half of the patients with HFpEF and is associated with echocardiographic evidence of more severe diastolic dysfunction and a higher prevalence of AF, doubling the risk of death or HF hospitalization.

The Longest Living Patient Supported With Left Ventricular Assist Device (14 Years).

Left ventricular assist devices (LVADs) improve survival and reduce symptoms in patients with advanced heart failure; however, the longer-term durability of LVADs remains uncertain especially with older-generation devices. In this case report, we describe the clinical course of a patient who has been successfully treated with the same HeartMate II LVAD for 14 years, the longest published and still ongoing LVAD support with the same originally implanted device.

Previous heart failure hospitalization, spironolactone, and outcomes in heart failure with preserved ejection fraction - a secondary analysis of TOPCAT.

BACKGROUND: Hospitalization for heart failure (HHF) is associated with poor postdischarge outcomes but the role of time since most recent HHF and potential treatment interactions are unknown. We aimed to assess history of and time since previous HHF, associations with composite of cardiovascular (CV) death and total HHF, first HHF and interactions with randomization to spironolactone, in heart failure with preserved ejection fraction. METHODS AND RESULTS: We assessed these objectives using uni- and multivariable regressions and spline analyses in TOPCAT-Americas. Among 1,765 patients, 66% had a previous HHF. Over a median of 2.9 years, 1,064 composite events of CV death or total HHFs occurred. Previous HHF was associated with more severe HF, and was independently associated with the composite outcome (HR 1.26, 95%CI 1.05-1.52, P = .014), and all secondary outcomes. A shorter time since most recent HHF appeared to be associated with subsequent first HHF, but not the composite of CV death or total HHF. Spironolactone had a significant interaction with previous HHF (interaction-P .046). Patients without a previous HHF had a larger effect of spironolactone on the composite outcome (HR 0.63, 95%CI 0.46-0.87, P = .005) than patients with a previous HHF (HR 0.91, 95%CI 0.78-1.06, P = .224). CONCLUSION: In TOPCAT-Americas, previous HHF was associated with CV death and first and total HHF. Duration since most recent HHF seemed to be associated with time to first HHF only. Spironolactone was associated with better outcomes in patients without a previous HHF. This interaction is hypothesis-generating and requires validation in future trials.

External validation of a deep learning algorithm for automated echocardiographic strain measurements.

Aims: Echocardiographic strain imaging reflects myocardial deformation and is a sensitive measure of cardiac function and wall-motion abnormalities. Deep learning (DL) algorithms could automate the interpretation of echocardiographic strain imaging. Methods and results: We developed and trained an automated DL-based algorithm for left ventricular (LV) strain measurements in an internal dataset. Global longitudinal strain (GLS) was validated externally in (i) a real-world Taiwanese cohort of participants with and without heart failure (HF), (ii) a core-lab measured dataset from the multinational prevalence of microvascular dysfunction-HF and preserved ejection fraction (PROMIS-HFpEF) study, and regional strain in (iii) the HMC-QU-MI study of patients with suspected myocardial infarction. Outcomes included measures of agreement [bias, mean absolute difference (MAD), root-mean-squared-error (RMSE), and Pearson's correlation (R)] and area under the curve (AUC) to identify HF and regional wall-motion abnormalities. The DL workflow successfully analysed 3741 (89%) studies in the Taiwanese cohort, 176 (96%) in PROMIS-HFpEF, and 158 (98%) in HMC-QU-MI. Automated GLS showed good agreement with manual measurements (mean ± SD): -18.9 ± 4.5% vs. -18.2 ± 4.4%, respectively, bias 0.68 ± 2.52%, MAD 2.0 ± 1.67, RMSE = 2.61, R = 0.84 in the Taiwanese cohort; and -15.4 ± 4.1% vs. -15.9 ± 3.6%, respectively, bias -0.65 ± 2.71%, MAD 2.19 ± 1.71, RMSE = 2.78, R = 0.76 in PROMIS-HFpEF. In the Taiwanese cohort, automated GLS accurately identified patients with HF (AUC = 0.89 for total HF and AUC = 0.98 for HF with reduced ejection fraction). In HMC-QU-MI, automated regional strain identified regional wall-motion abnormalities with an average AUC = 0.80. Conclusion: DL algorithms can interpret echocardiographic strain images with similar accuracy as conventional measurements. These results highlight the potential of DL algorithms to democratize the use of cardiac strain measurements and reduce time-spent and costs for echo labs globally.

Myeloperoxidase Inhibition in Heart Failure With Preserved or Mildly Reduced Ejection Fraction: SATELLITE Trial Results.

BACKGROUND: Inflammation is a key driver of heart failure with preserved left ventricular ejection fraction. AZD4831 inhibits extracellular myeloperoxidase, decreases inflammation, and improves microvascular function in preclinical disease models. METHODS AND RESULTS: In this double-blind phase 2a study (Safety and Tolerability Study of AZD4831 in Patients With Heart Failure [SATELLITE]; NCT03756285), patients with symptomatic heart failure, left ventricular ejection fraction of ≥40%, and elevated B-type natriuretic peptides were randomized 2:1 to once-daily oral AZD4831 5 mg or placebo for 90 days. We aimed to assess target engagement (primary end point: myeloperoxidase specific activity) and safety of AZD4831. Owing to coronavirus disease 2019, the study was terminated early after randomizing 41 patients (median age 74.0 years, 53.7% male). Myeloperoxidase activity was decreased by more than 50% from baseline to day 30 and day 90 in the AZD4831 group, with a placebo-adjusted decreased of 75% (95% confidence interval, 48, 88, nominal P < .001). No improvements were noted in secondary or exploratory end points, apart from a trend in Kansas City Cardiomyopathy Questionnaire overall summary score. No deaths or treatment-related serious adverse events occurred. AZD4831 treatment-related adverse events were generalized maculopapular rash, pruritus, and diarrhea (all n = 1). CONCLUSIONS: AZD4831 inhibited myeloperoxidase and was well tolerated in patients with heart failure and left ventricular ejection fraction of 40% or greater. Efficacy findings were exploratory owing to early termination, but warrant further clinical investigation of AZD4831. LAY SUMMARY: Few treatments are available for patients with the forms of heart failure known as heart failure with preserved or mildly reduced ejection fraction. Current treatments do not target inflammation, which may play an important role in this condition. We tested a new drug called AZD4831 (mitiperstat), which decreases inflammation by inhibiting the enzyme myeloperoxidase. Among the 41 patients in our clinical trial, AZD4831 had a good safety profile and inhibited myeloperoxidase by the expected amount. Results mean we can conduct further trials to see whether AZD4831 decreases the symptoms of heart failure and improves patients' ability to participate in physical exercise.

Acyl ghrelin increases cardiac output while preserving right ventricular-pulmonary arterial coupling in heart failure.

AIM: Acyl ghrelin increases cardiac output (CO) in heart failure with reduced ejection fraction (HFrEF). This could impair the right ventricular-pulmonary arterial coupling (RVPAC), both through an increased venous return and right ventricular afterload. We aim to investigate if acyl ghrelin increases CO with or without worsening the right-sided haemodynamics in HFrEF assessed by RVPAC. METHODS AND RESULTS: The Karolinska Acyl ghrelin Trial was a randomized double-blind placebo-controlled trial of acyl ghrelin versus placebo (120-min intravenous infusion) in HFrEF. RVPAC was assessed echocardiographically at baseline and 120 min. ANOVA was used for difference in change between acyl ghrelin versus placebo, adjusted for baseline values. Of the 30 randomized patients, 22 had available RVPAC (acyl ghrelin n = 12, placebo n = 10). Despite a 15% increase in CO in the acyl ghrelin group (from 4.0 (3.5-4.6) to 4.6 (3.9-6.1) L/min, P = 0.003), RVPAC remained unchanged; 5.9 (5.3-7.6) to 6.3 (4.8-7.5) mm·(m/s)-1 , P = 0.372, while RVPAC was reduced in the placebo group, 5.2 (4.3-6.4) to 4.8 (4.2-5.8) mm·(m/s)-1 , P = 0.035. Comparing change between groups, CO increased in the acyl ghrelin group versus placebo (P = 0.036) while RVPAC and the right ventricular pressure gradient remained unchanged. CONCLUSION: Treatment with acyl ghrelin increases CO while preserving or even improving RVPAC in HFrEF, possibly due to increased contractility, reduced PVR and/or reduced left sided filling pressures. These potential effects strengthen the role of acyl ghrelin therapy in HFrEF with right ventricular failure.

Heart failure registries - Future directions.

Heart failure (HF) is a growing, global public health issue. Despite advances in HF care, many challenges remain and HF outcomes are poor. Some of the major reasons for this are the lack of understanding and treatment for certain HF sub-types as well as the lack of implementation of treatment in areas where effective treatment exists. HF registries provide the opportunity to transform clinical research and patient care. Recently the registry-based randomized clinical trial has emerged as a pragmatic and inexpensive alternative to the gold standard in clinical trial design, the randomized controlled trial. Registries may also provide platforms for strategy trials, implementation trials, and screening. Using examples from the Swedish Heart Failure Registry and others, the present review provides insights into how registry-based research can address many of the unmet needs in HF.

N-terminal pro-B-type natriuretic peptide concentrations, testing and associations with worsening heart failure events.

AIMS: In patients with heart failure (HF), we aimed to assess (i) the time trends in N-terminal pro-B-type natriuretic peptide (NT-proBNP) testing; (ii) patient characteristics associated with NT-proBNP testing; (iii) distribution of NT-proBNP levels, focusing on the subgroups with (WHFE) vs. without (NWHFE) a worsening HF event, defined as an HF hospitalization; and (iv) changes of NT-proBNP levels over time. METHODS AND RESULTS: NT-proBNP testing and levels were investigated in HF patients enrolled in the Swedish Heart Failure Registry (SwedeHF) linked with the Stockholm CREAtinine Measurements project from January 2011 to December 2018. Index date was the first registration in SwedeHF. Patterns of change in NT-proBNP levels before (in the previous 6 ± 3 months) and after (in the following 6 ± 3 months) the index date were categorized as follows: (i) <3000 ng/L at both measurements = stable low; (ii) <3000 ng/L at the first measurement and ≥3000 ng/L at the second measurement = increased; (iii) ≥3000 ng/L at the first measurement and <3000 ng/L at the second measurement = decreased; and (iv) ≥3000 ng/L at both measurements = stable high. Univariable and multivariable logistic regression models, expressed as odds ratios (ORs) and 95% confidence intervals (95% CIs), were performed to assess the associations between (i) clinical characteristics and NT-proBNP testing and (ii) changes in NT-proBNP from 6 months prior to the index date and the index date and a WHFE. Consistency analyses were performed in HF with reduced ejection fraction (HFrEF) alone. A total of 4424 HF patients were included (median age 74 years, women 34%, HFrEF 53%), 33% with a WHFE. NT-proBNP testing increased over time, up to 55% in 2018, and was almost two-fold as frequent, and time to testing was less than half, in patients with WHFE vs. NWHFE. Independent predictors of testing were WHFE, higher heart rate, diuretic use, and preserved ejection fraction. Median NT-proBNP was 3070 ng/L (Q1-Q3: 1220-7395), approximately three-fold higher in WHFE vs. NWHFE. Compared with stable low NT-proBNP levels, increased (OR 4.27, 95% CI 2.47-7.37) and stable high levels (OR 2.48, 95% CI 1.58-3.88) were independently associated with a higher risk of WHFE. Results were consistent in the HFrEF population. CONCLUSIONS: NT-proBNP testing increased over time but still was only performed in half of the patients. Testing was associated with a WHFE, with features of more severe HF and for differential diagnosis purposes. Increased and stable high levels were associated with a WHFE. Overall, our data highlight the potential benefits of carrying further implementation of NT-proBNP testing in clinical practice.

Left ventricular ejection fraction digit bias and reclassification of heart failure with mildly reduced vs reduced ejection fraction based on the 2021 definition and classification of heart failure.

AIMS: Aims were to evaluate (1) reclassification of patients from heart failure with mildly reduced (HFmrEF) to reduced (HFrEF) ejection fraction when an EF = 40% was considered as HFrEF, (2) role of EF digit bias, ie, EF reporting favouring 5% increments; (3) outcomes in relation to missing and biased EF reports, in a large multinational HF registry. METHODS AND RESULTS: Of 25,154 patients in the European Society of Cardiology (ESC) HF Long-Term registry, 17% had missing EF and of those with available EF, 24% had HFpEF (EF≥50%), 21% HFmrEF (40%-49%) and 55% HFrEF (<40%) according to the 2016 ESC guidelines´ classification. EF was "exactly" 40% in 7%, leading to reclassifying 34% of the HFmrEF population defined as EF = 40% to 49% to HFrEF when applying the 2021 ESC Guidelines classification (14% had HFmrEF as EF = 41% to 49% and 62% had HFrEF as EF≤40%). EF was reported as a value ending with 0 or 5 in ∼37% of the population. Such potential digit bias was associated with more missing values for other characteristics and higher risk of all-cause death and HF hospitalization. Patients with missing EF had higher risk of all-cause and CV mortality, and HF hospitalization compared to those with recorded EF. CONCLUSIONS: Many patients had reported EF = 40%. This led to substantial reclassification of EF from old HFmrEF (40%-49%) to new HFrEF (≤40%). There was considerable digit bias in EF reporting and missing EF reporting, which appeared to occur not at random and may reflect less rigorous overall care and worse outcomes.

Novel Trial Designs in Heart Failure: Using Digital Health Tools to Increase Pragmatism.

PURPOSE OF REVIEW: Heart failure is an important clinical and public health issue. There is an urgent need to improve the efficiency of clinical trials in heart failure to rapidly identify new therapies and evidence-based implementation strategies for currently existing therapies. Electronic health (eHealth) platforms and digital health tools are being integrated into heart failure care. In this manuscript, we review opportunities to use these tools to potentially improve the design of and reduce the complexity of clinical trials in heart failure. RECENT FINDINGS: The PRECIS-2 tool outlines clinical trial design domains that are targets for pragmatism. We believe incorporating pragmatic design elements with the aid of eHealth platforms and digital health tools into clinical trials may help address the current complexity of clinical trials in heart failure and improve efficiency. In the manuscript, we provide examples from recent clinical trials across clinical trial design domains. We believe the current adoption of eHealth platforms and digital health tools is an opportunity improve the design of heart failure clinical trials. We specifically believe these tools can enhance pragmatism in clinical trials and reduce delays in generating high-quality evidence for new heart failure therapeutics.

Clinical Features of Heart Failure With Normal Ejection Fraction: Insights From the ASIAN-HF Registry.

Background: Heart failure and left ventricular ejection fraction in the normal range (HFnEF) (left ventricular ejection fraction [LVEF] of ≥55% for men and ≥60% for women) is understudied. Objectives: The authors aimed to characterize patients with HFnEF compared with those with preserved (≥50%) yet below the normal LVEF. Methods: In an Asian HF registry, clinical characteristics, echocardiographic features, and outcomes were compared across: 1) HFnEF; 2) heart failure with preserved left ventricular ejection fraction (HFpEF) (LVEF of ≥50%) and below normal LVEF; and 3) community-based controls without HF. Cluster analysis of echocardiographic parameters was performed and validated in an external cohort. Results: Among 1,765 patients with HFpEF (age 68 ± 12 years; 50% women), 1,313 (74.4%) had HFnEF. Compared with patients with HFpEF and below normal LVEF, patients with HFnEF had less coronary artery disease (33.7% vs 27.9%), greater LV wall thickness, and higher stroke volume, but similar 2-year age-adjusted all-cause mortality (HR: 0.8; 95% CI: 0.6-1.2). Five echocardiographic clusters with similar 2-year mortality were identified: 1) normal LV (normal structure despite increased filling pressure; least comorbidities) in 25%; 2) restrictive (smallest stroke volume; predominantly elderly women) in 26%; 3) hypertrophic (most concentric hypertrophy; more men) in 25%; 4) high output (greatest stroke volume; predominantly obese younger men) in 10%; and 5) atrial dominant (most left atrial myopathy; mainly elderly women with multiple comorbidities) in 10%. Similar patterns were found in the validation cohort. Conclusions: The majority of patients with HFpEF had normal LVEF, which consists of patients with different patterns of cardiac features and clinical characteristics. Results may carry implications for targeted treatment approaches in HFpEF.

The role of multimorbidity in patients with heart failure across the left ventricular ejection fraction spectrum: Data from the Swedish Heart Failure Registry.

AIMS: The aim of this analysis was to provide data on the overall comorbidity burden, both cardiovascular (CV) and non-CV, in a large real-world heart failure (HF) population across the ejection fraction (EF). METHODS AND RESULTS: Patients with HF from the Swedish HF Registry between 2000 and 2021 were included. Of 91 463 patients (median age 76 years [interquartile range 67-82]), 98% had at least one among the 17 explored comorbidities (94% at least one CV and 85% at least one non-CV comorbidity). All comorbidities, except for coronary artery disease (CAD), were more frequent in HF with preserved EF (HFpEF). Patients with multiple comorbidities were older, more likely female, inpatients, with HFpEF, worse New York Heart Association class and higher N-terminal pro-B-type natriuretic peptide levels. In a multivariable Cox model, 12 comorbidities were independently associated with a higher risk of death from any cause. The highest risk was associated with dementia (hazard ratio [HR] 1.55, 95% confidence interval [CI] 1.45-1.65), chronic kidney disease (HR 1.37, 95% CI 1.34-1.41), chronic obstructive pulmonary disease (HR 1.32, 95% CI 1.28-1.35). Obesity was associated with a lower risk of all-cause death (HR 0.81, 95% CI 0.79-0.84). CAD and valvular heart disease were associated with a higher risk of all-cause and CV mortality, but not non-CV mortality, whereas cancer and musculo-skeletal disease increased the risk of non-CV mortality. A significant interaction with EF was observed for several comorbidities. Occurrence of CV and non-CV outcomes was related to the number of CV and non-CV comorbidities, respectively. CONCLUSION: The burden of both CV and non-CV comorbidities was high in HF regardless of EF, but overall higher in HFpEF. Multimorbidity was associated with a high risk of death with a different burden on CV or non-CV outcomes.

Rationale and design of the ESC Heart Failure III Registry - Implementation and discovery.

AIMS: Heart failure outcomes remain poor despite advances in therapy. The European Society of Cardiology Heart Failure III Registry (ESC HF III Registry) aims to characterize HF clinical features and outcomes and to assess implementation of guideline-recommended therapy in Europe and other ESC affiliated countries. METHODS: Between 1 November 2018 and 31 December 2020, 10 162 patients with chronic or acute/worsening HF with reduced, mildly reduced, or preserved ejection fraction were enrolled from 220 centres in 41 European or ESC affiliated countries. The ESC HF III Registry collected data on baseline characteristics (hospital or clinic presentation), hospital course, diagnostic and therapeutic decisions in hospital and at the clinic visit; and on outcomes at 12-month follow-up. These data include demographics, medical history, physical examination, biomarkers and imaging, quality of life, treatments, and interventions - including drug doses and reasons for non-use, and cause-specific outcomes. CONCLUSION: The ESC HF III Registry will provide comprehensive and unique insight into contemporary HF characteristics, treatment implementation, and outcomes, and may impact implementation strategies, clinical discovery, trial design, and public policy.

Regional differences and coronary microvascular dysfunction in heart failure with preserved ejection fraction.

AIMS: In heart failure with preserved ejection fraction (HFpEF), regional heterogeneity of clinical phenotypes is increasingly recognized, with coronary microvascular dysfunction (CMD) potentially being a common shared feature. We sought to determine the regional differences in clinical characteristics and prevalence of CMD in HFpEF. METHODS AND RESULTS: We analysed clinical characteristics and CMD in 202 patients with stable HFpEF (left ventricular ejection fraction ≥40%) in Finland, Singapore, Sweden, and United States in the multicentre PROMIS-HFpEF study. Patients with unrevascularized macrovascular coronary artery disease were excluded. CMD was assessed using Doppler echocardiography and defined as coronary flow reserve (adenosine-induced vs. resting flow) < 2.5. Patients from Singapore had the lowest body mass index yet highest prevalence of hypertension, dyslipidaemia, and diabetes; patients from Finland and Sweden were oldest, with the most atrial fibrillation, chronic kidney disease, and high smoking rates; and those from United States were youngest and most obese. The prevalence of CMD was 88% in Finland, 80% in Singapore, 77% in Sweden, and 59% in the United States; however, non-significant after adjustment for age, sex, N-terminal pro-brain natriuretic peptide, smoking, left atrial reservoir strain, and atrial fibrillation. Associations between CMD and clinical characteristics did not differ based on region (interaction analysis). CONCLUSIONS: Despite regional differences in clinical characteristics, CMD was present in the majority of patients with HFpEF across different regions of the world with the lowest prevalence in the United States. This difference was explained by differences in patient characteristics. CMD could be a common therapeutic target across regions.