British Heart Foundation Centre Research Articles

Use of Win Statistics to Analyze Outcomes in the DAPA-HF and DELIVER Trials

BackgroundThe primary end point in most heart failure (HF) trials is a composite of time to a first worsening HF event or cardiovascular death. Prevention of recurrent events and improvements in symptoms/quality of life are also important for patients but are usually analyzed separately. Win statistics can integrate all these outcomes into a single composite end point, which is analyzed in hierarchical order, reflecting the clinical importance of each component.MethodsThe Dapagliflozin and Prevention of Adverse Outcomes in Heart Failure (DAPA-HF, n=4744) and Dapagliflozin Evaluation to Improve the Lives of Patients with Preserved Ejection Fraction Heart Failure (DELIVER, n=6263) trials enrolled patients with New York Heart Association class II, III, or IV HF, elevated natriuretic peptides, and either an ejection fraction of 40% or less (DAPA-HF) or greater than 40% and left atrial enlargement/left ventricular hypertrophy (DELIVER). We examined the effects of dapagliflozin compared with placebo on a hierarchical composite outcome, including cardiovascular death, total (first and recurrent) HF hospitalizations, total urgent HF visits, and improvement/deterioration in Kansas City Cardiomyopathy Questionnaire total symptom score (KCCQ-TSS; range from 0 to 100, with a higher score indicating fewer symptoms and physical limitations) at 8 months.ResultsFor this composite outcome, the win ratio was 1.30 (95% confidence interval [CI], 1.23 to 1.36) in the pooled cohort, 1.33 (95% CI, 1.23 to 1.43) in the DAPA-HF trial, and 1.27 (95% CI, 1.18 to 1.36) in the DELIVER trial. Win odds and net benefit in overall patients were 1.19 (95% CI, 1.14 to 1.24) and 8.7% (95% CI, 6.6 to 10.9%), respectively. In the overall pooled cohort, the majority of wins and losses were accounted for by KCCQ-TSS; 52.4% were settled by the KCCQ-TSS tier in the pooled cohort.ConclusionsIn both the DAPA-HF and DELIVER trials, dapagliflozin led to a significant improvement in composite outcomes that incorporated patient-reported outcomes along with total HF events, as well as cardiovascular deaths. These analyses provided a comprehensive presentation of win statistics and illustrated the utility and flexibility of win statistics in describing the effects of dapagliflozin in two recent clinical trials in patients with HF. (Funded by British Heart Foundation Centre of Research Excellence and others; clinical trial registration numbers, NCT03036124 and NCT03619213.)

Quantification of atrial cardiomyopathy disease severity by electroanatomic voltage mapping and cardiac magnetic resonance imaging

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): The authors acknowledge the support of the British Heart Foundation Centre for Research Excellence Award III (RE/18/5/34216). SEW is supported by the British Heart Foundation (FS/20/26/34952). Background Atrial late gadolinium enhancement (Atrial-LGE) and electroanatomic voltage mapping (Atrial-EAVM) quantify the anatomical and functional extent of atrial cardiomyopathy. Prior studies provide conflicting information relating to the level of agreement between these modalities for the assessment of atrial cardiomyopathy disease severity. Purpose We aimed to explore the relationships between, and outcomes from, these contrasting measures of atrial cardiomyopathy disease severity in patients with atrial fibrillation undergoing ablation. Methods Atrial-LGE and Atrial-EAVM was performed in patients undergoing first-time ablation for atrial fibrillation. Atrial cardiomyopathy disease severities were quantified using CEMRGApp and OpenEP[1] for Atrial-LGE and Atrial-EAVM, respectively. Correlations between modalities, their relationships with clinical features and their relationships with arrhythmia recurrence were assessed. Results Atrial-LGE and Atrial-EAVM quantification of atrial cardiomyopathy disease was performed In 123 atrial fibrillation patients (60±10 years, paroxysmal (n=58), persistent (n=65)) (Figure 1, panel A). Atrial-EAVM was moderately correlated with Atrial-LGE (r=0.41, P<0.001), with a mean fibrosis burden of 32.4±21.8% (Figure 1, panel B). The strength of the correlation was dependent on the thresholds chosen to define abnormal atrial tissue. The thresholds yielding the strongest correlation were IIR >0.97 (for Atrial-LGE) and voltage <1.17 mV (for Atrial-EAVM). Using these thresholds, agreement between modalities was strongest amongst patients in the highest tertile of fibrosis burden (mean of differences 5.9% (95% CI -30.4% to 42%)). Fibrosis burden was greater for Atrial-LGE than Atrial-EAVM (46.4±7.48% versus 13.7±7.13%, P<0.005) for patients in the lowest tertile of fibrosis burden (Figure 1, panel C). These patients were younger, had smaller atria and a greater frequency of paroxysmal atrial fibrillation than patients in the higher tertiles of fibrosis burden (Figure 2). Atrial cardiomyopathy disease severity was greater in patients with arrhythmia recurrence for both Atrial-EAVM (39.3±23.1% versus 28.5±20.2%, P=0.010) and Atrial-LGE (58.69±11.60 versus 53.33±9.63, P=0.011). In multivariable analysis, Atrial-LGE (OR 1.04 (95% CI 1.00-1.09), P=0.037) was independently associated with arrhythmia recurrence. Conclusions We demonstrate for the first time that the level of agreement between Atrial-EAVM and Atrial-LGE is dependent on the level of atrial cardiomyopathy disease severity. The functional consequences of atrial cardiomyopathy are most evident in patients with the highest anatomical extent of disease. This explains variations in prior studies and will inform future clinical applications of these techniques.

Volumetric quantification of peri-atrial fat inflammation in atrial fibrillation patients

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): British Heart Foundation Centre for Research Excellence Award III (RE/18/5/34216). SEW is supported by the British Heart Foundation (FS/20/26/34952). MCW is supported by the British Heart Foundation (FS/ICRF/20/26002) Introduction Peri-atrial fat may have pro-inflammatory and pro-fibrotic effects on atrial myocardium and increase the risk of developing atrial fibrillation. Both peri-atrial fat volume and density have been proposed as markers for atrial fibrillation risk, but prior studies considered only single-plane analysis or peri-atrial fat attenuation limited to the posterior left atrium. Purpose We aimed to assess total peri-atrial fat volume and attenuation and to explore the relationship between both parameters and the occurrence of atrial fibrillation. Methods Contrast-enhanced cardiac computed tomography (CT) imaging was performed pre-ablation in atrial fibrillation patients (n=32) and in control patients (n=37) without atrial fibrillation undergoing investigation for chest pain. We developed a volumetric method for peri-atrial fat segmentation and quantification using seg3D2 and CEMRGapp. Peri-atrial fat volume and attenuation (Hounsfield units, HU) were compared between patients with and without atrial fibrillation in univariable and multivariable analyses. A sensitivity analysis was performed to assess the impact of fat proximity to the left atrial wall. Results Atrial fibrillation participants were older (64±11 years vs 58±7 years, P=0.004) and more likely to have a history of coronary artery disease (50% vs 25%, P=0.03). Participants with atrial fibrillation had greater left atrial volume (88±28 ml vs 69±19 ml, P=0.002) and mass (29±6 g vs 14±0.9 g, P=0.018) compared to controls. Peri-atrial fat volume was greater in those with than without atrial fibrillation (18.5±6.6 ml vs 14.2±7.0 ml, adjusted odds ratio (AOR) per ml 1.21; 95% confidence interval [CI] 1.03-1.48), after adjusting for age, body mass index, comorbidities, left atrial dimensions and mass. However, total peri-atrial fat attenuation was not significantly different between groups (-74.8 vs -73.0 HU; AOR per HU 1.01; 95% CI 0.82-1.22). Sensitivity analysis did not identify an interaction between interrogation distance from the left atrial wall and peri-atrial fat attenuation on prevalent atrial fibrillation (p=0.872). Conclusion Peri-atrial fat volume, but not attenuation, is associated with prevalent atrial fibrillation. Further mechanistic studies are needed to study the role of peri-atrial fat in atrial fibrillation pathogenesis.

Feasibility of artificial intelligence-enhanced electrocardiogram (AI-ECG) analysis in the current clinical environment: An online survey

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): The study was funded by a University of Edinburgh Wellcome Trust iTPA award. The authors acknowledge the support of the British Heart Foundation Centre for Research Excellence Award III (RE/18/5/34216). SEW is supported by the British Heart Foundation (FS/20/26/34952). Background Artificial intelligence-enhanced electrocardiogram (AI-ECG) analysis offers the potential to identify patterns unrecognisable to human interpreters and broaden the ECG’s utility. However, current algorithms rely on waveform signals derived from digital ECGs for input data, and these cannot be readily obtained from paper-based ECGs. This potentially presents a barrier to adoption as numerous workplaces continue to use paper-based ECGs. The views of stakeholders on the current use of paper-based ECGs and the potential future application of AI-ECG analysis are unknown. Purpose To explore stakeholders’ views about current and future ECG use. To determine the perceived utility of AI-analysis of paper-based ECGs. Methods A web-based survey was designed using Qualtrics and distributed to a variety of healthcare professionals from numerous locations across the United Kingdom (UK). The survey consisted of 12 questions about participants’ perceptions relating to current and future paper-based ECG use and the perceived advantages and disadvantages of AI-ECG. Results In total, 43 healthcare professionals from 15 health provider organisations in the National Health Service (NHS) completed the survey. Paper-based ECGs were in use in 86% (37/43) of the respondents’ workplaces and 61% (26/43) felt that it would be useful if AI-based algorithms could analyse paper-based ECGs in addition to digital ECGs (Figure 1). Views on future prevalence of paper-based ECGs were split with 47% (20/43) responding that it is likely or extremely likely paper-based ECGs will still be in use in the next 5 years in the NHS. Perceived advantages of AI-based analysis included the potential to improve clinical decision making (51%, (22/43)) and optimisation of healthcare professionals’ work (leaving more time for clinical patient management) (47%, (20/43)) (Figure 2A). The inability to explain how algorithms determine results (56%, (24/43)), a lack of clarity over the accountability for the results (44%, (19/43)), and a reduction in learning opportunities (44%, (19/43)) were identified as potential issues associated with use of AI-ECG (Figure 2B). Conclusions Whilst AI-ECG offers potential to improve clinical care, there is currently a gap between research and the integration of AI-ECG into real-world practice. Paper-based ECGs remain prevalent within the NHS, and the current requirement for algorithms to receive signal data presents a barrier to current and future AI-ECG implementation. There is currently an unmet clinical need to develop algorithms capable of interpreting paper-based ECGs. AI-ECG analysis of paper-based ECGs could enable a wider range of healthcare professionals to capitalise on any benefits offered by AI-ECG.

Relationship between clinic and ambulatory blood pressure and mortality: an observational cohort study in 59 124 patients

Ambulatory blood pressure provides a more comprehensive assessment than clinic blood pressure, and has been reported to better predict health outcomes than clinic or home pressure. We aimed to examine associations of clinic and 24-h ambulatory blood pressure with all-cause and cardiovascular mortality in a large cohort of primary care patients referred for assessment of hypertension. We did an observational cohort study using clinic and ambulatory blood pressure data obtained from March 1, 2004, to Dec 31, 2014, from the Spanish Ambulatory Blood Pressure Registry. This registry included patients from 223 primary care centres from the Spanish National Health System in all 17 regions of Spain. Mortality data (date and cause) were ascertained by a computerised search of the vital registry of the Spanish National Institute of Statistics. Complete data were available for age, sex, all blood pressure measures, and BMI. For each study participant, follow-up was from the date of their recruitment to the date of death or Dec 31, 2019, whichever occurred first. Cox models were used to estimate associations between usual clinic or ambulatory blood pressure and mortality, adjusted for confounders and additionally for alternative measures of blood pressure. For each measure of blood pressure, we created five groups (ie, fifths) defined by quintiles of that measure among those who subsequently died. During a median follow-up of 9·7 years, 7174 (12·1%) of 59 124 patients died, including 2361 (4·0%) from cardiovascular causes. J-shaped associations were observed for several blood pressure measures. Among the top four baseline-defined fifths, 24-h systolic blood pressure was more strongly associated with all-cause death (hazard ratio [HR] 1·41 per 1 - SD increment [95% CI 1·36-1·47]) than clinic systolic blood pressure (1·18 [1·13-1·23]). After adjustment for clinic blood pressure, 24-h blood pressure remained strongly associated with all-cause deaths (HR 1·43 [95% CI 1·37-1·49]), but the association between clinic blood pressure and all-cause death was attenuated when adjusted for 24-h blood pressure (1·04 [1·00-1·09]). Compared with the informativeness of clinic systolic blood pressure (100%), night-time systolic blood pressure was most informative about risk of all-cause death (591%) and cardiovascular death (604%). Relative to blood pressure within the normal range, elevated all-cause mortality risks were observed for masked hypertension (HR 1·24 [95% CI 1·12-1·37]) and sustained hypertension (1·24 [1·15-1·32]), but not white-coat hypertension, and elevated cardiovascular mortality risks were observed for masked hypertension (1·37 [1·15-1·63]) and sustained hypertension (1·38 [1·22-1·55]), but not white-coat hypertension. Ambulatory blood pressure, particularly night-time blood pressure, was more informative about the risk of all-cause death and cardiovascular death than clinic blood pressure. Spanish Society of Hypertension, Lacer Laboratories, UK Medical Research Council, Health Data Research UK, National Institute for Health and Care Research Biomedical Research Centres (Oxford and University College London Hospitals), and British Heart Foundation Centre for Research Excellence.

Relationship between endothelin-1, heart failure with reduced ejection fraction and dapagliflozin: findings from DAPA-HF

Abstract Background Circulating Endothelin-1 (ET-1) is associated with heart failure (HF) severity and has also been widely implicated in the pathophysiology of renal disease. However, its prognostic importance and relationship with kidney function in patients with HFrEF receiving contemporary treatment is uncertain. Purpose To investigate the association of ET-1 with heart failure outcomes, as well as change in kidney function; and the efficacy of dapagliflozin according to baseline serum ET-1 in the Dapagliflozin And Prevention of Adverse outcomes in Heart Failure trial (DAPA-HF). Methods Serum ET-1 was measured at randomization and at 12 months and analysed using a Microfluidics immunoassay. We investigated the incidence of the primary outcome (cardiovascular death or worsening HF), and analysed change in kidney function according to tertile of baseline ET-1 concentration. Additionally, we assessed whether baseline ET-1 modified the treatment effect of dapagliflozin. Results Of 4744 randomized participants, 3048 (64.2%) had a baseline ET-1 measurement: tertile 1 (≤3.28 pg/mL, n=1016), tertile 2 (>3.28 to 4.41 pg/mL, n=1022), and tertile 3 (>4.41 pg/mL, n=1010). Patients with higher baseline ET-1 concentrations were more likely male, obese and to have lower LVEF, lower eGFR, worse functional status, and elevated NT-proBNP and high-sensitivity troponin-T. Adjusting for other predictive variables including NT-proBNP, higher baseline ET-1 was independently associated with worse outcomes and steeper decline in kidney function: adjusted hazard ratio (aHR) for the primary outcome of 1.95 (1.53–2.50) for tertile 3 and 1.36 (95% CI 1.06–1.75) for tertile 2; aHR for worsening HF of 2.54 (1.82–3.53) for tertile 3 and 1.54 (1.10–2.18) for tertile 2; aHR for cardiovascular death of 1.39 (1.01–1.92) for tertile 3 and 1.13 (0.82–1.57) for tertile 2; and eGFR slope −3.19 (95% CI −3.66 to −2.72) mL/min/1.73 m2 per year in tertile 3 versus −2.06 (−2.51 to −1.62) in tertile 2 and −2.35 (−2.79 to −1.91) in tertile 1, p for difference (eGFR slope)=0.002. The benefit of dapagliflozin was consistent regardless of baseline ET-1, whether analysed according to tertiles or as a continuous variable, with p-interaction for primary outcome 0.47 and 0.10 respectively. Compared to placebo, there was a trend to reduction in ET-1 level at 12 months with dapagliflozin (difference −0.12 pg/mL, p-value=0.07). Conclusions Baseline ET-1 concentration was independently associated with clinical outcomes and with more rapid decline in kidney function. The benefit of dapagliflozin was consistent across the range of ET-1 concentrations measured. Funding Acknowledgement Type of funding sources: Foundation. Main funding source(s): The DAPA-HF trial was funded by AstraZeneca. Professor John McMurray is supported by a British Heart Foundation Centre of Research Excellence Grant RE/18/6/34217.

A comprehensive study of the incremental prognostic value of novel biomarkers in PARADIGM-HF (Bio-PREDICT-HF)

Abstract Background Although multiple novel biomarkers have individually been shown to predict outcomes in patients with HFrEF, the value of these over and above conventional clinical and laboratory variables, plus natriuretic peptides, is uncertain. Purpose To test the incremental predictive value of 11 novel biomarkers added to a recent prognostic model 1 (PREDICT-HF) derived in PARADIGM-HF and validated in ATMOSPHERE and the Swedish heart failure registry. The PREDICT-HF model includes clinical variables, standard laboratory variables, and BNP or NT-proBNP. Methods 1559 participants enrolled in PARADIGM-HF had all 11 biomarkers of interest measured. These reflected different pathophysiological pathways: (i) myocyte injury (high sensitivity cardiac troponin T), (ii) cardiac remodelling and inflammation (growth stimulation expressed gene 2, growth differentiation factor-15 and galectin-3), (iii) extracellular matrix remodelling (matrix metalloproteinase-2, matrix metalloproteinase-9, tissue inhibitor of metalloproteinase-1), (iv) neurohormonal pathways (aldosterone) and (v) renal dysfunction and injury (cystatin C, kidney injury molecule-1 and urinary albumin to creatinine ratio). The incremental prognostic value of these biomarkers was evaluated using Harrell's C statistic. Results The mean age of participants studied was 67.3 (SD 9.9) years, 1254 (80%) were men and 1103 (71%) were in NYHA class II. During a median follow-up of 31 months, 197 patients died and 300 experienced the primary composite outcome (cardiovascular death or heart failure hospitalization). When each candidate biomarker (log unit) was added individually to the PREDICT-HF base model, GDF-15, ST2, TIMP1, cystatin C, hsTnT and UACR were independent predictors of all-cause mortality (Table 1). GDF-15, TIMP1, hs-TnT and cystatin C consistently increased the risk of both all-cause mortality and the primary outcome. Individuals who had all 4 biomarkers elevated (compared to none elevated) had the highest risk: HR for all-cause mortality 3.65 (2.01–6.64), p<0.0001. Adding these 4 biomarkers to the baseline PREDICT HF model improved the C statistic for all-cause mortality from 0.726 to 0.745. Conclusion Several novel biomarkers provide meaningful additional prognostic information in patients with HFrEF. A multimarker approach incorporating biomarkers reflecting different pathophysiological pathways added most information. This approach may be useful in refining risk and targeting treatment. Funding Acknowledgement Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The PARADIGM-HF trial was funded by Novartis.J.J.V.M is supported by a British Heart Foundation Centre of Excellence Grant

Antiplatelet therapy use for the secondary prevention of cardiovascular disease in 2009–2017: a population-wide retrospective cohort study of Scotland

Abstract Background Few studies have analysed the adequacy of antiplatelet therapy (APT) use for secondary prevention of atherosclerotic cardiovascular disease (ASCVD). Some studies found utilisation to be suboptimal. However, information on the extent of APT use at different treatment stages and over time, and the role of particular individual characteristics, is limited. Purpose To use large-scale population-wide individual patient data to investigate the extent of, and determinants for, suboptimal use of effective APT, in order to identify patient groups that could be targeted to improve medication use. Methods This retrospective open cohort study used anonymised large-scale population-wide individual patient NHS Scotland data (hospital admissions, national death records, prescribing information and speciality mental health admissions) for all individuals hospitalised for ASCVD (based on ICD-10 discharge codes) in Scotland between 1 October 2009 and 31 December 2017. APT initiation was defined as a prescription of APT within 90 days of ASCVD hospital discharge with dispensing within 60 days of the prescription. Adherence was defined as ≥80% of days covered with dispensed therapy. Discontinuation of APT was defined as a treatment gap of 180 days or more since initiation. Multivariable cross-sectional logistic regression and Cox proportional hazards models were used to study the relevance of patient characteristics (e.g., demographic, clinical, socioeconomic) to the likelihood of, respectively, initiating or discontinuing APT. Findings are reported for all ASCVD events and, separately, for myocardial infarction (MI), ischaemic stroke, peripheral arterial disease (PAD) and other ASCVD events. Results Of 150,728 individuals hospitalised for ASCVD (excluding any diagnosis of atrial fibrillation), 16% did not initiate any APT. Initiation was less common in women (22% less likely than men), people aged ≥70 or <50 (21% and 39% less likely for patients in their 70s and 80s respectively vs. 60s; 26% less likely for patients below age 50 vs. 60s), people living in more deprived areas, people receiving specialist mental health care and people with multiple morbidities (Figure). There was substantial variation for lack of initiation across ASCVD types (e.g., MI 6%, PAD: 32%). In 2015/17, 72% of MI patients and 69% of patients undergoing percutaneous coronary intervention received guideline-recommended dual-APT. While on treatment, 93% of users were adherent. However, about a quarter (23%) discontinued treatment. Similar characteristics linked to lack of initiation of APT were associated with an increased risk of discontinuation. Conclusions APT initiation and persistence remain suboptimal, especially in women, people aged below 50 years and 70 years or older, people with multiple morbidities or mental illness, and following non-MI ASCVD events. This needs to be addressed by clinicians and policy-makers to further reduce cardiovascular risk. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): Oxford British Heart Foundation Centre of Research Excellence (BHF CRE) Pump Priming Scheme; Medical Research Council Doctoral Training Programme (MRC DTP) studentship.

Outcomes related to IGFBP-7 in patients with heart failure and reduced ejection fraction and effects of dapagliflozin: findings from DAPA-HF

Abstract Introduction Insulin-like growth factor binding protein 7 (IGFBP-7) has been proposed as a novel prognostic biomarker in heart failure, but the association between IGFBP-7 and cardiovascular outcomes has not been examined in a large cohort of patients with heart failure and reduced ejection fraction (HFrEF). Purpose In this post-hoc analysis of the Dapagliflozin And Prevention of Adverse outcomes in Heart Failure trial (DAPA-HF) we examined the relationship between plasma IGFBP-7 level and outcomes in patients with HFrEF, the effect of dapagliflozin according to IGFBP-7 level and change in IGFBP-7 at 12 months. Methods Patients in NYHA class II–IV with LVEF ≤40% and elevated NT-proBNP were included in DAPA-HF. Participants were randomly allocated to dapagliflozin 10mg or matching placebo. In this analysis, patients were categorized by IGFBP-7 tertile. The primary outcome was a composite of cardiovascular death or worsening HF event; secondary outcomes were components of the primary outcome and all-cause mortality. The risk of each outcome was compared across thirds of IGFBP-7 using Cox regression models with adjustment for NT-proBNP and high-sensitivity troponin T as well as: randomised treatment, age, sex, race, region, systolic blood pressure, heart rate, ejection fraction, estimated glomerular filtration rate, NYHA class, history of HF hospitalisation, ischaemic aetiology of HF, hypertension, stroke, atrial fibrillation, prior MI and stratified by diabetes status. The efficacy of dapagliflozin was assessed according to baseline IGFBP-7 level. Change in IGFBP-7 at 12 months was assessed using the ratio of geometric means. Results 3158 patients had measurement of IGFBP-7 at baseline. The median value of IGFBP-7 was 192 ng/mL (interquartile range 158–246). Patients in the highest third of IGFBP-7 levels had more advanced HF, with higher NYHA class and NT-proBNP, had worse renal function and more type 2 diabetes. Patients in the highest third had the highest rate of the primary outcome (Figure 1). The adjusted hazard ratio (aHR) for the primary endpoint (with lowest third of IGFBP-7 as reference) was 0.94 (95% CI 0.74–1.20) for middle third and 1.49 (95% CI 1.17–1.89) for top third. The corresponding aHRs for worsening HF event were 0.99 (95% CI 0.72–1.36) for middle third and 1.84 (95% CI 1.35–2.50) for top third. Cardiovascular and all-cause mortality did not vary by IGFBP-7 tertile. The benefit of dapagliflozin was consistent regardless of baseline IGFBP-7 (p for interaction for primary endpoint = 0.34). The change in IGFBP-7 from baseline to 12 months did not differ between placebo and dapagliflozin. Conclusions Elevation of IGFBP-7 in patients with HFrEF was associated with more adverse HF outcomes, even after adjustment for both NT-proBNP and hsTnT. The treatment benefit of dapagliflozin did not vary by baseline IGFBP-7. Funding Acknowledgement Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): The DAPA-HF trial was funded by AstraZeneca.CA and JJVM are supported by a British Heart Foundation Centre of Research Excellence Grant.

Is Asymptomatic Severe Aortic Stenosis Still a Waiting Game?

Is Asymptomatic Severe Aortic Stenosis Still a Waiting Game?

Future Leaders to Watch – Christopher Toepfer and Manuel Schmid

ABSTRACTFuture Leaders to Watch is a series of interviews with the first authors of a selection of papers published in Biology Open, helping early-career researchers promote themselves alongside their papers. Christopher Toepfer and Manuel Schmid are co-first authors on ‘Myosin super relaxation (SRX) a perspective on fundamental biology, human disease, and cardiac therapeutics’, published in BiO. Christopher is a Sir Henry Wellcome Postdoctoral Fellow and British Heart Foundation Centre of Research Excellence (CRE) Intermediate Transition Fellow in the department of Cardiovascular Medicine at the Radcliffe Department of Medicine, University of Oxford, UK. Manuel is a Research Assistant in the department of Cardiovascular Medicine at the Radcliffe Department of Medicine, University of Oxford, UK. They are investigating the mechanisms that control heart function and impact acquired and inherited cardiovascular conditions.

Medium-term effects of SARS-CoV-2 infection on multiple vital organs, exercise capacity, cognition, quality of life and mental health, post-hospital discharge.

BackgroundThe medium-term effects of Coronavirus disease (COVID-19) on organ health, exercise capacity, cognition, quality of life and mental health are poorly understood.MethodsFifty-eight COVID-19 patients post-hospital discharge and 30 age, sex, body mass index comorbidity-matched controls were enrolled for multiorgan (brain, lungs, heart, liver and kidneys) magnetic resonance imaging (MRI), spirometry, six-minute walk test, cardiopulmonary exercise test (CPET), quality of life, cognitive and mental health assessments.FindingsAt 2–3 months from disease-onset, 64% of patients experienced breathlessness and 55% reported fatigue. On MRI, abnormalities were seen in lungs (60%), heart (26%), liver (10%) and kidneys (29%). Patients exhibited changes in the thalamus, posterior thalamic radiations and sagittal stratum on brain MRI and demonstrated impaired cognitive performance, specifically in the executive and visuospatial domains. Exercise tolerance (maximal oxygen consumption and ventilatory efficiency on CPET) and six-minute walk distance were significantly reduced. The extent of extra-pulmonary MRI abnormalities and exercise intolerance correlated with serum markers of inflammation and acute illness severity. Patients had a higher burden of self-reported symptoms of depression and experienced significant impairment in all domains of quality of life compared to controls (p<0.0001 to 0.044).InterpretationA significant proportion of patients discharged from hospital reported symptoms of breathlessness, fatigue, depression and had limited exercise capacity. Persistent lung and extra-pulmonary organ MRI findings are common in patients and linked to inflammation and severity of acute illness.FundingNIHR Oxford and Oxford Health Biomedical Research Centres, British Heart Foundation Centre for Research Excellence, UKRI, Wellcome Trust, British Heart Foundation.

How Should We Sequence the Treatments for Heart Failure and a Reduced Ejection Fraction?: A Redefinition of Evidence-Based Medicine.

How Should We Sequence the Treatments for Heart Failure and a Reduced Ejection Fraction?: A Redefinition of Evidence-Based Medicine.

Abnormalities of the lymphatic system and impaired fluid clearance in patients with heart failure with preserved ejection fraction

Abstract Background Coronary and skeletal muscle microvascular dysfunction have been proposed as main factors in the pathogenesis of Heart Failure with Preserved Ejection Fraction (HFpEF). However, assessment of systemic arterial function has only been indirect thus far; most importantly, no direct link between systemic microvasculature and congestion, one of the core characteristics of the syndrome, has yet been investigated. Purpose To provide direct functional and anatomical characterisation of the systemic microvasculature and to explore in vivo parameters of capillary fluid extravasation and lymphatic clearance in HFpEF. Methods In 16 patients with HFpEF and 16 age- and sex-matched healthy controls (72±6 and 68±5 years, respectively) we determined peripheral microvascular filtration coefficient (proportional to vascular permeability and area) and isovolumetric pressure (above which lymphatic drainage cannot compensate for fluid extravasation) by venous occlusion plethysmography and collected a skin biopsy for vascular immunohistochemistry and gene expression analysis (TaqMan). Additionally, we measured brachial flow-mediated dilatation (FMD) and assessed by wire myography the vascular function of resistance arteries isolated from gluteal subcutaneous fat biopsies. Results Skin biopsies in patients with HFpEF showed rarefaction of small blood vessels (82±31 vs 112±21 vessels/mm2; p=0.003) and in ex-vivo analysis (n=6/group) we found defective relaxation of peripheral resistance arteries (p&amp;lt;0.001). Accordingly, post-ischaemic hyperaemic response (fold-change vs baseline, 4.6±1.6 vs 6.7±1.7; p=0.002) and FMD (3.9±2.1 vs 5.6±1.5%; p=0.014) were found to be reduced in patients with HFpEF compared to controls. In the skin of patients with HFpEF we also observed a reduced number (85±27 vs 130±60 vessels/mm2; p=0.012) but larger average diameter of lymphatic vessels (42±19 vs 26±9 μm2; p=0.007) compared to control subjects. These changes were paralleled by reduced expression of LYVE1 (p&amp;lt;0.05) and PROX1 (p&amp;lt;0.001), key determinants of lymphatic differentiation and function. Whilst patients with HFpEF had reduced peripheral capillary fluid extravasation compared to controls (microvascular filtration coefficient, leg 33.1±13.3 vs 48.4±15.2, p&amp;lt;0.01; trend for arm 49.9±20.5 vs 66.3±30.1, p=0.09), they had lower lymphatic clearance (isovolumetric pressure: leg 22±4 vs 16±4 mmHg, p&amp;lt;0.005; arm 25±5 vs 17±4 mmHg, p&amp;lt;0.001). Conclusions We provide direct evidence of systemic dysfunction and rarefaction of small blood vessels in patients with HFpEF. Despite a reduced microvascular filtration coefficient, which is in keeping with microvascular rarefaction, the clearance of extravasated fluid in HFpEF is limited by an anatomically and functionally defective lymphatic system. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): British Heart Foundation Centre of Research Excellence Award

Plasma extracellular vesicles modulate immune cell gene expression following myocardial infarction

Abstract Background Myocardial infarction (MI) induces activation of immune cells and alters their gene expression en route to the injured myocardium but the underlying mechanisms coordinating immune cell programming following MI remain unknown. Plasma extracellular vesicle (EV) numbers are elevated in MI, correlate with the extent of myocardial injury and mobilises immune cells from the splenic reserve to peripheral blood. Here, we describe the role of plasma EV-microRNAs (miRs) in the modulation of peripheral blood mononuclear cell (PBMC) transcriptomes post-MI. Methods PBMCs were exposed to plasma EVs followed by whole transcriptome RNA-sequencing. Plasma EVs were isolated by size-exclusion chromatography and ultra-centrifugation (2 hours at 120,000 x g) from patients presenting with ST-segment elevation MI (STEMI) (N=9) and non-STEMI (NSTEMI) (N=11) control patients. Plasma EVs were characterised by western blot and Nanoview for EV markers CD9 and CD63, transmission electron microscopy (TEM) for morphology and Nanoparticle Tracking Analysis for size and concentration. High sensitive C-reactive protein (hs-CRP) and PCSK9 were determined in plasma by ELISA and compared to plasma EV number using Pearson's correlation. Plasma EV-miRs were measured by Agilent microarray and miR-mRNA putative targets assessed by TargetScanHuman. Results Plasma EVs were positive for EV markers CD9 and CD63, displayed typical EV morphology by TEM and had a heterogeneous size and concentration distribution profile as determined by Nanoparticle Tracking Analysis. Plasma EV number correlated significantly with hs-CRP at presentation (R2= 0.20 and P&amp;lt;0.05). miRNA array analysis revealed STEMI plasma-EVs contained significantly more miR-4487 (P&amp;lt;0.001), miR-6511b-5p (P&amp;lt;0.001), miR-4508 (P&amp;lt;0.001) vs NSTEMI control plasma-EVs at the time of injury. STEMI-plasma-EVs induced differential gene expression in PBMCs vs. NSTEMI-control-plasma-EVs. Gene set enrichment analysis (GSEA) showed STEMI-plasma-EVs upregulated pro-inflammatory pathways including: interferon-α (IFN-α) (P&amp;lt;0.01), IFN-γ (P&amp;lt;0.01), tumour necrosis factor-α (TNF-α) (P&amp;lt;0.01) and interleukin-6 (IL-6)-STAT3 signalling of the acute phase response (P&amp;lt;0.05). miR-4487 (P&amp;lt;0.001) and miR-6511-5p (P&amp;lt;0.05) predicted mRNA targets were significantly enriched in PBMC transcriptomes following treatment with STEMI plasma-EVs. Conclusions Plasma EVs mediating immune cell transcriptional programming following MI by promoting inflammatory pathways in PBMCs is a novel finding. Targeting PBMCs with EVs may allow modulation of the immune response following myocardial injury, to perturb inflammatory immune mediated damage following ischaemic injury. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): British Heart Foundation Centre of Research Excellence Awards, British Heart Foundation Project Grant, Novo Nordisk Fonden the Tripartite Immunometabolism Consortium and Wellcome Institutional Strategic Support Fund (ISSF)

Determinants of statin initiation and discontinuation in the secondary prevention of atherosclerotic cardiovascular disease in Scotland during 2009–2017

Abstract Background Previous studies have shown that use of statins for secondary prevention of cardiovascular disease (CVD) is suboptimal. However, the role of particular individual characteristics at different treatment stages is limited. Purpose To use large-scale population-wide individual patient data to investigate reasons for suboptimal use of effective CVD medications, in order to identify patient groups that could be targeted to improve medication adherence. Methods This observational longitudinal study used anonymised linked NHS Scotland administrative data (General/Acute Inpatient and Day Case, the National Records of Scotland and the Prescribing Information System) for all individuals hospitalised for an atherosclerotic CVD event (based on ICD-10 discharge codes) in Scotland between 1 April 2009 and 31 December 2017. Statin initiation was defined as individuals being prescribed statin therapy within 90 days from index discharge and dispensed within 60 days from that prescription. Discontinuation was defined as the start of first statin treatment gap of 180 days or more since initiation. Multivariate logistic regression and Cox proportional hazards models were used to study the relevance of patient characteristics (e.g. demographic, clinical, socio-economic) and admission calendar year to the likelihood of, respectively, initiating or discontinuing statin treatment. Findings are reported for all CVD events and, separately, for myocardial infarction (MI), ischaemic stroke (IS) and peripheral arterial disease (PAD). Results Of the 178,113 patients hospitalised for CVD, 19% did not initiate statin treatment. Among the 144,077 patients initiating (40% on high-intensity statins, as defined by NICE guidelines), 25% discontinued treatment within 2 years. Initiation was less common in women (29% less likely than men), older people (22% and 50% less likely for patients in their 70s and 80s respectively vs. 60s), people living in more deprived areas, people receiving specialist mental health care, people with multiple morbidities and people not taking statin prior to admission (Figure). Most of these characteristics were also associated with a decreased likelihood of initiating high-intensity statins, as well as an increased risk of discontinuing statin therapy. In later years, levels of statin initiation, including on higher-intensity statins (58% of statin initiators in 2015–17 vs. 32% in 2009–11), and statin persistence have improved. Conclusions Rates of statin initiation and discontinuation remain suboptimal, especially among women, older people and people with multiple morbidities or mental health illness. Figure 1. Patient characteristics associated with initiation and discontinuation of statin treatment after atherosclerotic CVD event. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): British Heart Foundation Centre of Research Excellence (Pump Priming Scheme), Medical Research Council UK

Distinct transcriptional and functional features of regenerative mouse neonatal cardiac macrophages

Abstract Background The myocardium of neonatal mice is able to regenerate after myocardial infarction (MI), whereas in adults the formation of scar predominantly occurs following heart injury. Macrophages are involved in the fibrotic response in adult mouse hearts, but also required for successful regeneration in neonates. Recent work has demonstrated that macrophages directly contribute collagen to scar formation following MI. Furthermore, neonatal and adult cardiac macrophages have divergent transcriptional responses to injury. Here, we describe differential transcriptomes and signalling pathways of these functionally distinct neonatal resident cardiac macrophages. Methods Hearts from neonatal P1, P7 and adult CD1 mice (n=3 per group) were digested with collagenase to produce a single cell suspension. Macrophages were isolated by FACS and identified as Ly6G, F4/80+, LyChi/lo cells. Macrophage whole transcriptomes were measured by Illumina RNA-sequencing. Transcript abundance was quantified from raw reads by Salmon and analysis of differentially expressed (DE) genes was carried out with DESeq2. Gene Ontology (GO) enrichment analysis of DE genes was performed with PANTHER. Genes were ranked according to p-value for differential expression, then these ranked genes were used for Gene Set Enrichment Analysis (GSEA) to detect enriched gene sets from the Molecular Signatures Database. Results RNA-sequencing of transcriptomes from neonatal P1, P7 and adult mouse macrophages from hearts highlighted distinct gene expression profiles. The greatest differences were between P1 vs. adult (4,494 differentially expressed (DE) genes at p&amp;lt;0.05) and P7 vs. adult (3,347 DE genes), whereas P1 and P7 macrophages were relatively similar (478 DE genes). A set of 171 genes was found to be DE in P1 vs. P7 and adult macrophages. This P1-specific gene set was highly enriched for GO terms including matrix disassembly (29-fold enrichment, p&amp;lt;0.05) and regulation of chemokine production (12-fold enrichment, p&amp;lt;0.05). GSEA analysis highlighted key functional pathways that were differentially regulated in P1 macrophages, including oxidative phosphorylation and glycolysis, the E2F transcription factors and cell cycle regulators Myc and p53. Conclusions We highlight key genes and pathways distinct to resident neonatal cardiac macrophages to determine the basis for the regenerative capacity of these cells. Interestingly, while genes associated with extracellular matrix were previously shown to be altered after MI in neonatal macrophages, similar differences were also observed here in the basal state of resident neonatal macrophages. We also identified transcriptional and cell cycle regulators linked to the programming and regenerative capacity of these macrophages. The functional differences found in neonatal macrophages might represent potential targets for novel therapeutics. Funding Acknowledgement Type of funding source: Foundation. Main funding source(s): Novo Nordisk Fonden the Tripartite Immunometabolism Consortium (NNF15CC0018486), British Heart Foundation Centre of Research Excellence Awards (RE/13/1/30181)

A short term treatment with a Mek1/2 inhibitor promotes myocardial arteriogenesis and perfusion in vivo: focus on cardiac mural cells

Abstract Background Arteriogenesis is crucial for heart recovery after ischaemia, but cellular and molecular mechanisms able to foster this phenomenon are still poorly characterised. Purpose To discover novel pro-arteriogenic approaches by exploiting cardiac mural cells endowed with arteriogenic capacity: pericytes (PCs) and vascular smooth muscle cells (VSMCs). Methods and results We derived human and murine CD31neg CD34pos cardiac PCs (cPCs) from myocardial samples of adult subjects and confirmed the pericyte phenotype and function in vitro. We discovered that the withdrawal of EGF and bFGF from the culture media induces the differentiation of cPCs into contractile VSMCs. Molecular investigations of pathways associated with the two factors showed that the Mek1/2-Erk1/2 signalling exerts an inhibitory transcriptional control on contractile VSMC genes. Screening of compounds able to interfere with this pathway revealed that PD0325901 – a potent Mek1/2 inhibitor (MeKi) tested in clinical trials for the treatment of cancer – activates the VSMC phenotype in cPCs. We observed a similar effect on coronary artery VSMCs. Next, we interrogated the effect of PD0325901 on cardiac arteriogenesis in vivo. Adult C57BL6/J mice were given the MeKi 10 mg/kg/day or vehicle (DMSO), orally for 14 days (n=11/group). At the endpoint, echocardiographic evaluation of left ventricle (LV) function and dimensions (n=6/group) showed no difference in comparison with the respective baseline in both groups. Effective inhibition of Mek1/2 in the heart of PD-treated mice was confirmed by the reduced immunostaining for the phosphorylated form of Erk1/2. The MeKi cardiotoxicity was ruled out by assessment of cardiomyocytes and vascular cells apoptosis (Tunel) and plasmatic levels of cTn-I. Histological analyses of the hearts (n=5/group) showed an increase in small arterioles (diameter &amp;lt;20μm) density in the LV of PD-mice compared with the DMSO group (16.4 vs 11.7 art/mm2). No change was observed for the capillary density. The drug promoted the maturation of VSMCs within both small and large (&amp;gt;20μm) arterioles, as shown by the higher ratio between the areas of the vascular wall occupied by the mature contractile marker SM myosin heavy chain and the synthetic/early contractile marker alpha-SM actin (αSMA). The PD treatment reduced the fraction of small arterioles covered with a CD34pos layer (53% vs 70% of total arterioles), along with a lower ratio between the areas occupied by adventitial CD34pos cells and αSMApos VSMCs, suggesting a contribution of cPCs to the arteriolar remodelling. Last, the drug improved the LV myocardial perfusion in the PD- vs the DMSO-group (6.8 vs 5.3 ml/min/g of LV tissue, n=6/group). Conclusions We show that a short treatment with a Mek1/2 inhibitor stimulates myocardial arteriogenesis and perfusion without either inducing cardiotoxicity or deteriorating heart function. This may be a novel, intriguing approach to promote therapeutic arteriogenesis. Funding Acknowledgement Type of funding source: Public grant(s) – National budget only. Main funding source(s): British Heart Foundation Centre for Vascular Regeneration II

P4436Impaired myocardial healing in patients with diabetes after ST-Elevation Myocardial Infarction

Abstract Background Diabetes mellitus (DM) significantly increases mortality following myocardial infarction (MI). The underlying mechanism explaining this adverse prognosis is not completely understood. Purpose This study sought to investigate the characteristics of myocardial healing after MI in DM patients. Methods 62 recruited ST-elevation myocardial infarction (STEMI) patients (21 with DM and 41 controls) underwent acute (1–3 days post-STEMI) and 6 months (6M) follow-up cardiac magnetic resonance scans (CMR). Control cases were matched for the peak troponin levels and area at risk on the acute CMR scans. Blood samples were obtained 6, 24, 48 hours and 6 months after STEMI. Results Despite similar severity of the initial ischaemic injury, DM patients had lower myocardial salvage index (MSI) and as a result larger final infarct size at 6 months. Further segment-based analysis of the acute CMR scans showed significantly prolonged T1-mapping values in all segments including non-ischaemic myocardium in DM patients and poorer recovery of the late gadolinium enhancement (LGE) of the infarcted segments in that group. Additionally, DM patients had higher monocyte counts 24 hours post-MI (1.2±0.4x109/μl DM vs 0.88±0.3 x109/μl control, p=0.001). We found that HbA1C correlated with monocyte count measured 24 hours after STEMI (r=0.577, p=0.006, n=21). HbA1C also predicted myocardial salvage index (MSI) at 6M post STEMI in the DM patients (r=0.891, p=0.017, n=13). Conclusions DM patients presenting with STEMI have increased peripheral blood monocytosis and larger final infarct size compared with STEMI patients without DM. Poorly controlled DM predisposes to adverse cardiac remodelling after STEMI. Acknowledgement/Funding OHSRC Research Grant, National Institute for Health Research (NIHR), British Heart Foundation Centre of Excellence Oxford

Neurotransmitter Switching in Sympathetic Neurons Coupled to Beta‐Adrenergic Signalling in Hypertensive States

IntroductionHypertension can be caused by sympathetic over‐activity1,2. β‐blockers are a main‐stay treatment strategy for conditions caused by enhanced sympathetic drive3 however, the precise mechanisms that mediate and sustain the beneficial effects of β‐blockers in disease remain unclear4,5. Conventional wisdom suggests the main beneficial effects of β‐blockers reside within the myocardium; however, emerging evidence indicates that another beneficial effect of β‐blockers in disease may reside in sympathetic neurons.AimWe investigated whether β‐adrenoceptors (βARs) are present on cardiac post‐ganglionic sympathetic neurons (PGSNs) in human and rat; and facilitate neurotransmission in a feed‐forward manner.MethodsWe used a combination of RNA sequencing, quantitative real‐time (qRT)‐PCR, Enzyme Linked Immunosorbent Assays (ELISAs) and immunocytochemistry to investigate whether sympathetic βARs are present on human and rat sympathetic stellate ganglia. We subsequently used Förster Resonance Energy Transfer (FRET) microscopy and Ca2+ Imaging to establish whether intracellular second messenger signalling coupled to presynaptic βARs is impaired in hypertensive states; contributing to impaired cyclic nucleotide (cN) signalling and Ca2+ dysfunction. Finally, we used high pressure liquid chromatography coupled to electrochemical detection (HPLC‐EC) to assess which neurotransmitters are present within the cardiac‐sympathetic ganglia in healthy and diseased states, to test the idea that Adr may act as the preferential sympathetic neurotransmitter in disease.ResultsWe identified the presence of βARs on human and rat stellate ganglia. In diseased neurons from the rat, we measured enhanced βAR‐mediated cAMP‐PKA‐Ca2+ signalling, predominantly via β2AR activation. Moreover, we identified the presence of the adrenaline (Adr) synthesising enzyme, Phenylethanolamine‐N‐methyltransferase (PNMT) in human and rat neurons; and measured greater Adr content and evoked release in diseased rat neurons.ConclusionWe conclude that neurotransmitter switching, resulting in enhanced Adr release, may provide presynaptic positive feedback on βARs to promote further release that leads to greater postsynaptic excitability. Targeting neuronal βAR downstream signalling could provide therapeutic opportunity to minimise end‐organ damage caused by sympathetic over‐activity.Support or Funding InformationThis project was funded by the Wellcome Trust OXION Initiative, NIH SPARC Initiative and the British Heart Foundation Centre of Research Excellence (BHF CRE). We acknowledge The High‐Throughput Genomics Group at the Wellcome Trust Centre for Human Genetics (funded by Wellcome Trust grant reference 090532/Z/09/Z) for the generation of the Sequencing data. We wish to acknowledge our collaborators Dr. Ajijola, Dr. Shivkumar and Dr. Ardell at UCLA for kindly extracting and shipping human sympathetic stellate ganglia from donor patients #19, #23 and #24. We wish to thank Dr. Threlfell in our department for her help and expertise with HPLC‐EC experimental design and protocols.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.