Exogenous Transforming Growth Factor-β1 and Its Helminth-Derived Mimic Attenuate the Heart's Inflammatory Response to Ischemic Injury and Reduce Mature Scar Size

Coronary reperfusion after acute ST-elevation myocardial infarction (STEMI) is standard therapy to salvage ischemic heart muscle. However, subsequent inflammatory responses within the infarct lead to further loss of viable myocardium. Transforming growth factor (TGF)-β1 is a potent anti-inflammatory cytokine released in response to tissue injury. The aim of this study was to investigate the protective effects of TGF-β1 after MI. In patients with STEMI, there was a significant correlation (P = 0.003) between higher circulating TGF-β1 levels at 24 hours after MI and a reduction in infarct size after 3 months, suggesting a protective role of early increase in circulating TGF-β1. A mouse model of cardiac ischemia reperfusion was used to demonstrate multiple benefits of exogenous TGF-β1 delivered in the acute phase. It led to a significantly smaller infarct size (30% reduction, P = 0.025), reduced inflammatory infiltrate (28% reduction, P = 0.015), lower intracardiac expression of inflammatory cytokines IL-1β and chemokine (C-C motif) ligand 2 (>50% reduction, P = 0.038 and 0.0004, respectively) at 24 hours, and reduced scar size at 4 weeks (21% reduction, P = 0.015) after reperfusion. Furthermore, a low-fibrogenic mimic of TGF-β1, secreted by the helminth parasite Heligmosomoides polygyrus, had an almost identical protective effect on injured mouse hearts. Finally, genetic studies indicated that this benefit was mediated by TGF-β signaling in the vascular endothelium.

Cellular Senescence, Mitochondrial Dysfunction, and Their Link to Cardiovascular Disease

Cardiovascular diseases (CVDs), a group of disorders affecting the heart or blood vessels, are the primary cause of death worldwide, with an immense impact on patient quality of life and disability. According to the World Health Organization, CVD takes an estimated 17.9 million lives each year, where more than four out of five CVD deaths are due to heart attacks and strokes. In the decades to come, an increased prevalence of age-related CVD, such as atherosclerosis, coronary artery stenosis, myocardial infarction (MI), valvular heart disease, and heart failure (HF) will contribute to an even greater health and economic burden as the global average life expectancy increases and consequently the world's population continues to age. Considering this, it is important to focus our research efforts on understanding the fundamental mechanisms underlying CVD. In this review, we focus on cellular senescence and mitochondrial dysfunction, which have long been established to contribute to CVD. We also assess the recent advances in targeting mitochondrial dysfunction including energy starvation and oxidative stress, mitochondria dynamics imbalance, cell apoptosis, mitophagy, and senescence with a focus on therapies that influence both and therefore perhaps represent strategies with the most clinical potential, range, and utility.

Clinical outcomes of coronary intravascular lithotripsy in patients with stent failure (COIL registry)

BACKGROUND

Intravascular lithotripsy (IVL) has been demonstrated to be an effective treatment of calcified de novo coronary lesions. Safety data on the use of IVL within stented segments are lacking. We sought to evaluate the safety, feasibility, and long-term outcomes of IVL in patients with stent failure.

METHODS

This was a retrospective multi-centre registry that included consecutive patients with stent failure who had undergone IVL treatment. The primary efficacy endpoint was procedural success defined as residual stenosis <30% (determined by quantitative coronary angiography analysis) in patients who survived hospital admission without in-hospital adverse events. Major adverse cardiovascular events (MACE) were defined as the composite endpoints of cardiovascular death, spontaneous myocardial infarction, and target vessel revascularisation at one-year follow up.

RESULTS

102 patients were included in this study. Mean age was 73 ± 9 years and 81% were male. The duration from previous stent implantation and IVL treatment was 24 (interquartile range 7-76) months, of which 10.8% received IVL for acute under-expanded stent. IVL treatment allowed significant improvement in both minimal lumen diameter (1.14 ± 0.60 to 2.53 ± 0.59, P < 0.001) and degree of stenosis (66.8 ± 19.9 to 20.3 ± 11.3%, P < 0.001). The rate of procedural success was 78.4% (80/102 of patients). The one-year MACE was 15.7%. Ostial disease (HR 5.16; 95% CI 1.19 to 22.33; P = 0.028) and lesion length (HR 1.05; 95% CI 1.01 to 1.10; P = 0.010) were independently associated with one-year MACE.

CONCLUSIONS

In patients with stent failure, IVL is a safe and feasible treatment for this high-risk group.

Modification of the GRACE Risk Score for Risk Prediction in Patients With Acute Coronary Syndromes

Importance

The Global Registry of Acute Coronary Events (GRACE) risk score, a guideline-recommended risk stratification tool for patients presenting with acute coronary syndromes (ACS), does not consider the extent of myocardial injury.

Objective

To assess the incremental predictive value of a modified GRACE score incorporating high-sensitivity cardiac troponin (hs-cTn) T at presentation, a surrogate of the extent of myocardial injury.

Design, Setting, and Participants

This retrospectively designed longitudinal cohort study examined 3 independent cohorts of 9803 patients with ACS enrolled from September 2009 to December 2017; 2 ACS derivation cohorts (Heidelberg ACS cohort and Newcastle STEMI cohort) and an ACS validation cohort (SPUM-ACS study). The Heidelberg ACS cohort included 2535 and the SPUM-ACS study 4288 consecutive patients presenting with a working diagnosis of ACS. The Newcastle STEMI cohort included 2980 consecutive patients with ST-elevation myocardial infarction treated with primary percutaneous coronary intervention. Data were analyzed from March to June 2023.

Exposures

In-hospital, 30-day, and 1-year mortality risk estimates derived from an updated risk score that incorporates continuous hs-cTn T at presentation (modified GRACE).

Main Outcomes and Measures

The predictive value of continuous hs-cTn T and modified GRACE risk score compared with the original GRACE risk score. Study end points were all-cause mortality during hospitalization and at 30 days and 1 year after the index event.

Results

Of 9450 included patients, 7313 (77.4%) were male, and the mean (SD) age at presentation was 64.2 (12.6) years. Using continuous rather than binary hs-cTn T conferred improved discrimination and reclassification compared with the original GRACE score (in-hospital mortality: area under the receiver operating characteristic curve [AUC], 0.835 vs 0.741; continuous net reclassification improvement [NRI], 0.208; 30-day mortality: AUC, 0.828 vs 0.740; NRI, 0.312; 1-year mortality: AUC, 0.785 vs 0.778; NRI, 0.078) in the derivation cohort. These findings were confirmed in the validation cohort. In the pooled population of 9450 patients, modified GRACE risk score showed superior performance compared with the original GRACE risk score in terms of reclassification and discrimination for in-hospital mortality end point (AUC, 0.878 vs 0.780; NRI, 0.097), 30-day mortality end point (AUC, 0.858 vs 0.771; NRI, 0.08), and 1-year mortality end point (AUC, 0.813 vs 0.797; NRI, 0.056).

Conclusions and Relevance

In this study, using continuous rather than binary hs-cTn T at presentation, a proxy of the extent of myocardial injury, in the GRACE risk score improved the mortality risk prediction in patients with ACS.

Fractalkine/CX3CR1 in Dilated Cardiomyopathy: A Potential Future Target for Immunomodulatory Therapy?

Dilated cardiomyopathy (DCM) is a cardiac condition with structural and functional impairment, where either the left ventricle or both ventricular chambers are enlarged, coinciding with reduced systolic pump function (reduced ejection fraction, rEF). The prevalence of DCM is more than 1:250 individuals, and mortality largely due to heart failure in two-third of cases, and sudden cardiac death in one-third of patients. Damage to the myocardium, whether from a genetic or environmental cause such as viruses, triggers inflammation and recruits immune cells to the heart to repair the myocardium. Examination of myocardial biopsy tissue often reveals an inflammatory cell infiltrate, T lymphocyte (T cell) infiltration, or other activated immune cells. Despite medical therapy, adverse outcomes for DCM remain. The evidence base and existing literature suggest that upregulation of CX3CR1, migration of immune cells, together with cytomegalovirus (CMV) seropositivity is associated with worse outcomes in patients with dilated cardiomyopathy. We hypothesise that this potentially occurs through cardiac inflammation and fibrosis, resulting in adverse remodelling. Immune modulators to target this pathway may potentially improve outcomes above and beyond current guideline-recommended therapy.

Arginine Vasopressin Plays a Role in Microvascular Dysfunction After ST-Elevation Myocardial Infarction

Background Coronary microvascular dysfunction (CMD) predicts mortality after ST-elevation-myocardial infarction (STEMI). Arginine vasopressin (AVP) may be implicated, but data in humans are lacking, and no study has investigated the link between arginine vasopressin and invasive measures of CMD. Methods and Results We invasively assessed CMD in 55 patients with STEMI treated with primary percutaneous coronary intervention (PPCI), by measuring the index of microcirculatory resistance after PPCI. In a separate group of 45 patients with STEMI/PPCI, recruited for a clinical trial, we measured infarct size and microvascular obstruction with cardiac magnetic resonance (CMR) imaging at 1 week and 12 weeks post-STEMI. Serum copeptin was measured at 4 time points before and after PPCI in all patients with STEMI. Plasma copeptin levels fell from 92.5 pmol/L before reperfusion to 6.4 pmol/L at 24 hours. Copeptin inversely correlated with diastolic, but not systolic, blood pressure (r=-0.431, P=0.001), suggesting it is released in response to myocardial ischemia. Persistently raised copeptin at 24 hours was correlated with higher index of microcirculatory resistance (r=0.372, P=0.011). Patients with microvascular obstruction on early CMR imaging showed a trend toward higher admission copeptin, which was not statistically significant. Copeptin levels were not associated with infarct size on either early or late CMR. Conclusions Patients with CMD after STEMI have persistently elevated copeptin at 24 hours, suggesting arginine vasopressin may contribute to microvascular dysfunction. Arginine vasopressin receptor antagonists may represent a novel therapeutic option in patients with STEMI and CMD.

Microvascular Obstruction in Acute Myocardial Infarction, a Potential Therapeutic Target

Microvascular obstruction (MVO) is a recognised phenomenon following mechanical reperfusion in patients presenting with ST-segment elevation myocardial infarction (STEMI). Invasive and non-invasive modalities to detect and measure the extent of MVO vary in their accuracy, suggesting that this phenomenon may reflect a spectrum of pathophysiological changes at the level of coronary microcirculation. The importance of detecting MVO lies in the observation that its presence adds incremental risk to patients following STEMI treatment. This increased risk is associated with adverse cardiac remodelling seen on cardiac imaging, increased infarct size, and worse patient outcomes. This review provides an outline of the pathophysiology, clinical implications, and prognosis of MVO in STEMI. It describes historic and novel pharmacological and non-pharmacological therapies to address this phenomenon in conjunction with primary PCI.

Activation of telomerase by TA-65 enhances immunity and reduces inflammation post myocardial infarction

Myocardial infarction (MI) accelerates immune ageing characterised by lymphopenia, expansion of terminally differentiated CD8+ T-lymphocytes (CD8+ TEMRA) and inflammation. Pre-clinical data showed that TA-65, an oral telomerase activator, reduced immune ageing and inflammation after MI. We conducted a double blinded randomised controlled pilot trial evaluating the use of TA-65 to reduce immune cell ageing in patients following MI. Ninety MI patients aged over 65 years were randomised to either TA-65 (16 mg daily) or placebo for 12 months. Peripheral blood leucocytes were analysed by flow cytometry. The pre-defined primary endpoint was the proportion of CD8+ T-lymphocytes which were CD8+ TEMRA after 12 months. Secondary outcomes included high-sensitivity C-reactive protein (hsCRP) levels. Median age of participants was 71 years. Proportions of CD8+ TEMRA did not differ after 12 months between treatment groups. There was a significant increase in mean total lymphocyte count in the TA-65 group after 12 months (estimated treatment effect: + 285 cells/μl (95% CI: 117-452 cells/ μ l, p < 0.004), driven by significant increases from baseline in CD3+, CD4+, and CD8+ T-lymphocytes, B-lymphocytes and natural killer cells. No increase in lymphocyte populations was seen in the placebo group. At 12 months, hsCRP was 62% lower in the TA-65 group compared to placebo (1.1 vs. 2.9 mg/L). Patients in the TA-65 arm experienced significantly fewer adverse events (130 vs. 185, p = 0.002). TA-65 did not alter CD8+ TEMRA but increased all major lymphocyte subsets and reduced hsCRP in elderly patients with MI after 12 months.

Fractalkine Signalling (CX3CL1/CX3CR1 Axis) as an Emerging Target in Coronary Artery Disease

Acute myocardial infarction (MI) is the most common and dramatic complication of atherosclerosis, which, despite successful reperfusion therapy, can lead to incident heart failure (HF). HF occurs when the healing process is impaired due to adverse left ventricular remodelling, and can be the result of so-called ischaemia/reperfusion injury (IRI), visualised by the development of intramyocardial haemorrhage (IMH) or microvascular obstruction (MVO) in cardiac MRI. Thus far, translation of novel pharmacological strategies from preclinical studies to target either IRI or HF post MI have been largely unsuccessful. Anti-inflammatory therapies also carry the risk of affecting the immune system. Fractalkine (FKN, CX3CL1) is a unique chemokine, present as a transmembrane protein on the endothelium, or following cleavage as a soluble ligand, attracting leukocyte subsets expressing the corresponding receptor CX3CR1. We have shown previously that the fractalkine receptor CX3CR1 is associated with MVO in patients undergoing primary PCI. Moreover, inhibition of CX3CR1 with an allosteric small molecule antagonist (KAND567) in the rat MI model reduces acute infarct size, inflammation, and IMH. Here we review the cellular biology of fractalkine and its receptor, along with ongoing studies that introduce CX3CR1 as a future target in coronary artery disease, specifically in patients with myocardial infarction.

Effector T cell chemokine IP-10 predicts cardiac recovery and clinical outcomes post-myocardial infarction

Background and aims

Preclinical data suggest that activation of the adaptive immune system is critical for myocardial repair processes in acute myocardial infarction. The aim of the present study was to determine the clinical value of baseline effector T cell chemokine IP-10 blood levels in the acute phase of ST-segment elevation myocardial infarction (STEMI) for the prediction of the left ventricular function changes and cardiovascular outcomes after STEMI.

Methods

Serum IP-10 levels were retrospectively quantified in two independent cohorts of STEMI patients undergoing primary percutaneous coronary intervention.

Results

We report a biphasic response of the effector T cell trafficking chemokine IP-10 characterized by an initial increase of its serum levels in the acute phase of STEMI followed by a rapid reduction at 90min post reperfusion. Patients at the highest IP-10 tertile presented also with more CD4 effector memory T cells (CD4 TEM cells), but not other T cell subtypes, in blood. In the Newcastle cohort (n=47), patients in the highest IP-10 tertile or CD4 TEM cells at admission exhibited an improved cardiac systolic function 12 weeks after STEMI compared to patients in the lowest IP-10 tertile. In the Heidelberg cohort (n=331), STEMI patients were followed for a median of 540 days for major adverse cardiovascular events (MACE). Patients presenting with higher serum IP-10 levels at admission had a lower risk for MACE after adjustment for traditional risk factors, CRP and high-sensitivity troponin-T levels (highest vs. rest quarters: HR [95% CI]=0.420 [0.218-0.808]).

Conclusion

Increased serum levels of IP-10 in the acute phase of STEMI predict a better recovery in cardiac systolic function and less adverse events in patients after STEMI.

Senescent cardiomyocytes contribute to cardiac dysfunction following myocardial infarction

Myocardial infarction is a leading cause of morbidity and mortality. While reperfusion is now standard therapy, pathological remodelling leading to heart failure remains a clinical problem. Cellular senescence has been shown to contribute to disease pathophysiology and treatment with the senolytic navitoclax attenuates inflammation, reduces adverse myocardial remodelling and results in improved functional recovery. However, it remains unclear which senescent cell populations contribute to these processes. To identify whether senescent cardiomyocytes contribute to disease pathophysiology post-myocardial infarction, we established a transgenic model in which p16 (CDKN2A) expression was specifically knocked-out in the cardiomyocyte population. Following myocardial infarction, mice lacking cardiomyocyte p16 expression demonstrated no difference in cardiomyocyte hypertrophy but exhibited improved cardiac function and significantly reduced scar size in comparison to control animals. This data demonstrates that senescent cardiomyocytes participate in pathological myocardial remodelling. Importantly, inhibition of cardiomyocyte senescence led to reduced senescence-associated inflammation and decreased senescence-associated markers within other myocardial lineages, consistent with the hypothesis that cardiomyocytes promote pathological remodelling by spreading senescence to other cell-types. Collectively this study presents the demonstration that senescent cardiomyocytes are major contributors to myocardial remodelling and dysfunction following a myocardial infarction. Therefore, to maximise the potential for clinical translation, it is important to further understand the mechanisms underlying cardiomyocyte senescence and how to optimise senolytic strategies to target this cell lineage.

The RNA editor ADAR2 promotes immune cell trafficking by enhancing endothelial responses to interleukin-6 during sterile inflammation

Immune cell trafficking constitutes a fundamental component of immunological response to tissue injury, but the contribution of intrinsic RNA nucleotide modifications to this response remains elusive. We report that RNA editor ADAR2 exerts a tissue- and stress-specific regulation of endothelial responses to interleukin-6 (IL-6), which tightly controls leukocyte trafficking in IL-6-inflamed and ischemic tissues. Genetic ablation of ADAR2 from vascular endothelial cells diminished myeloid cell rolling and adhesion on vascular walls and reduced immune cell infiltration within ischemic tissues. ADAR2 was required in the endothelium for the expression of the IL-6 receptor subunit, IL-6 signal transducer (IL6ST; gp130), and subsequently, for IL-6 trans-signaling responses. ADAR2-induced adenosine-to-inosine RNA editing suppressed the Drosha-dependent primary microRNA processing, thereby overwriting the default endothelial transcriptional program to safeguard gp130 expression. This work demonstrates a role for ADAR2 epitranscriptional activity as a checkpoint in IL-6 trans-signaling and immune cell trafficking to sites of tissue injury.

Senescent cardiomyocytes contribute to cardiac dysfunction following myocardial infarction

Myocardial infarction is a leading cause of morbidity and mortality. While reperfusion is now standard therapy, pathological remodeling leading to heart failure remains a clinical problem. Cellular senescence has been shown to contribute to disease pathophysiology and treatment with the senolytic navitoclax attenuates inflammation, reduces adverse myocardial remodeling and results in improved functional recovery. However, it remains unclear which senescent cell populations contribute to these processes. To identify whether senescent cardiomyocytes contribute to disease pathophysiology post-myocardial infarction, we established a transgenic model in which p16 (CDKN2A) expression was specifically knocked-out in the cardiomyocyte population. Following myocardial infarction, mice lacking cardiomyocyte p16 expression demonstrated no difference in cardiomyocyte hypertrophy but exhibited improved cardiac function and significantly reduced scar size in comparison to control animals. This data demonstrates that senescent cardiomyocytes participate in pathological myocardial remodeling. Importantly, inhibition of cardiomyocyte senescence led to reduced senescence-associated inflammation and decreased senescence-associated markers within other myocardial lineages, consistent with the hypothesis that cardiomyocytes promote pathological remodeling by spreading senescence to other cell-types. Collectively this study presents a novel demonstration that senescent cardiomyocytes are major contributors to myocardial remodeling and dysfunction following a myocardial infarction. Therefore, to maximize the potential for clinical translation, it is important to further understand the mechanisms underlying cardiomyocyte senescence and how to optimize senolytic strategies to target this cell lineage.

Very Early Discharge After Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction: Mortality Outcomes at Six Months

BACKGROUND

Current guidelines recommend that low risk patients presenting with ST-segment elevation myocardial infarction (STEMI) and undergoing uncomplicated primary percutaneous coronary intervention (PPCI) can be discharged home in 48-72 h. We report the safety of early discharge in STEMI patients undergoing uncomplicated PPCI after 24-h stay in-hospital.

METHODS

We performed a retrospective analysis of prospectively collected data of consecutive patients presenting with STEMI between January 2014 and December 2020. One- and 6-month mortality rates were compared between patients who underwent next day (early discharge group) and two days in-hospital stay (standard discharge group).

RESULTS

Of 6119 STEMI patients, 4033 were included in the analysis, of whom 1674 (42 %) underwent early discharge. Patients in the early discharge group were younger, more likely to be male, and had a lower peak troponin. Both groups had similar ischemia- and door-to-balloon time, but anterior STEMI were less frequent in the early discharge group. The 1- and 6-month mortality rate for the whole cohort was 0.6 % and 1.3 %, respectively. After adjustment, there were no significant differences in the 1-month [HR 0.54; 95 % CI (0.20 to 1.47), P = 0.23] and 6-month mortality [HR 0.73; 95 % CI (0.38 to 1.41), P = 0.35] between early and standard discharge groups. Age, admission heart rate and chronic obstructive lung disease were identified as independent predictors of 6-month mortality in patients who underwent early discharge strategy.

CONCLUSION

Our data confirms safety of next day discharge of patients presenting with STEMI after successful PPCI and uncomplicated post-procedural course.

Heart Disease and Ageing: The Roles of Senescence, Mitochondria, and Telomerase in Cardiovascular Disease

During ageing molecular damage leads to the accumulation of several hallmarks of ageing including mitochondrial dysfunction, cellular senescence, genetic instability and chronic inflammation, which contribute to the development and progression of ageing-associated diseases including cardiovascular disease. Consequently, understanding how these hallmarks of biological ageing interact with the cardiovascular system and each other is fundamental to the pursuit of improving cardiovascular health globally. This review provides an overview of our current understanding of how candidate hallmarks contribute to cardiovascular diseases such as atherosclerosis, coronary artery disease and subsequent myocardial infarction, and age-related heart failure. Further, we consider the evidence that, even in the absence of chronological age, acute cellular stress leading to accelerated biological ageing expedites cardiovascular dysfunction and impacts on cardiovascular health. Finally, we consider the opportunities that modulating hallmarks of ageing offer for the development of novel cardiovascular therapeutics.

Immunosenescence profiles of lymphocyte compartments and multiple long-term conditions (multimorbidity) in very old adults: The Newcastle 85+ Study

Immunosenescence, a decline in immune system function, has been linked to several age-related diseases and ageing syndromes. Very old adults (aged ≥ 85 years) live with multiple long-term conditions (MLTC, also known as multimorbidity)-a complex phenomenon of poor health defined by either counts, indices, or patterns, but little is known about the relationship between an ageing immune system and MLTC in this age group. We utilised baseline data from the Newcastle 85+ Study to investigate the associations between previously defined immunosenescence profiles of lymphocyte compartments and MLTC counts and patterns (from 16 chronic diseases/ageing syndromes). Seven hundred and three participants had MLTC and complete data for all 16 conditions, a median and mean of 5 (range 2-11) and 62.2% had ≥ 5 conditions. Three distinct MLTC patterns emerged by clustering: Cluster 1 ('Low frequency cardiometabolic-cerebrovascular diseases', n = 209), Cluster 2 ('High ageing syndromes-arthritis', n = 240), and Cluster 3 ('Hypertensive-renal impairment', n = 254). Although having a more senescent phenotype, characterised by higher frequency of CD4 and CD8 senescence-like effector memory cells and lower CD4/CD8 ratio, was not associated with MLTC compared with less senescent phenotype, the results warrant further investigation, including whether immunosenescence drives change in MLTC and influences MLTC severity in late adulthood.

Activation of mitochondrial telomerase reverses relative lymphopenia post myocardial infarction: results from the randomised, double-blinded TACTIC phase IIa pilot trial

Background

Immune ageing is a phenomenon which includes lymphopenia, expansion of pro-inflammatory T-lymphocyte subsets and telomere shortening. While lymphopenia predicts mortality after myocardial infarction (MI), MI itself leads to both an increase in terminally differentiated memory CD8+ T-lymphocytes (CD8+ TEMRAs) and a decrease in telomere length. Activation of telomerase has been shown to ameliorate lymphopenia, and improve heart function after MI in mouse models. TA-65 is an oral telomerase activator, which may ameliorate immune ageing and improve outcome after MI.

Methods

This double-blinded, randomized placebo-controlled pilot study evaluated the use of TA-65 in 90 MI patients over 65 years, the average onset age for immune ageing. Patients were randomised to either TA-65 (16 mg daily, n=45) or placebo (n=45) for 12 months. The majority of patients underwent percutaneous coronary intervention (87%) or coronary artery bypass surgery (2%) as treatment for their index MI. The pre-defined primary endpoint was the proportion of CD8+ TEMRA T-lymphocytes at 12 months, a marker of immune ageing. A linear mixed effects model was used for the analysis.

Results

The proportion of CD8+ TEMRAs after 12 months did not differ between the 2 treatment groups, although only increased significantly in the placebo group (+2.2%, 95% CI: 0.14–4.24). TA-65 was well tolerated, with total adverse events lower in the treatment group (TA-65 vs. placebo group: n=130 vs. n=185). We observed at 12 months a 62% reduction in mean high-sensitivity CRP (hsCRP: TA-65 vs. placebo group: 1.1±0.9 vs. 2.9±6.4 mg/L) and a 15%-increase in mean peripheral blood lymphocytes in TA-65 after 12 months. In the whole sample, among those who were treated with TA-65 compared to Placebo, after 12 months peripheral blood lymphocytes increased (+285 cells /μl, 95% CI: 117–452). The latter was due to significant increases in the TA-65 group from baseline to 12 months across all major lymphocyte populations: CD3+ (+15%), CD4+ (+14%),CD8+ T-lymphocytes (+19%), B-lymphocytes (+17%) and natural killer cells (+12%), while no changes occurred in major lymphocyte populations in the placebo group over the course of the study.

Conclusion

In this randomised clinical trial, we found that while CD8+ TEMRAs were not significantly altered after 12 months, the telomerase activator TA-65 significantly increased all major lymphocyte subsets and substantially reduced hsCRP at 12 months in patients with MI. These findings suggest TA-65 holds great promise in potentially reducing inflammation while improving an age-related decline in major lymphocyte populations, thereby enhancing immunity. A larger, multicentre, powered phase IIb efficacy trial to examine the potential effect of TA-65 in prognosis and heart function after MI is therefore warranted.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): TA-Science, New York, USA

Relative monocytosis predicts the presence and severity of coronary artery disease on CT coronary angiography in patients with stable angina symptoms

Background

Monocytes, among other leucocytes, are crucially involved in the pathogenesis of atherosclerosis, but the value of peripheral blood leucocyte counts in predicting the presence or absence of atherosclerotic coronary artery disease (CAD) is unknown.

Purpose

Investigating whether circulating counts of monocytes, lymphocytes and neutrophils predict CAD on computed tomography coronary angiography (CTCA) in patients presenting with stable chest pain.

Methods

All patients investigated with CTCA in our centre in the year 2021 were screened (n=1564). Patients presenting via the Rapid Access Chest Pain clinic were retrospectively identified, and those with a Full Blood Count from the 6 months prior to clinic were included (n=330). Traditional cardiovascular risk factors were ascertained from the clinic letter. CAD was defined as any epicardial stenosis &gt;25% on CTCA. Patients with CAD were further classified as having either single or multivessel disease (left main stem disease was considered multivessel), and non-obstructive or obstructive disease (any stenosis &gt;70% was considered obstructive).

Results

Patients with CAD had significantly higher mean monocyte count than those without CAD (0.61 vs. 0.55x109/L, p=0.004), while no differences were observed between groups in lymphocyte or neutrophil count. Monocyte count increased further with more severe CAD, being higher in patients with multivessel compared to single-vessel disease (0.62 vs. 0.60x109/L; p for trend including no CAD =0.012), and in patients with obstructive compared to non-obstructive disease (0.62 vs. 0.60x109/L; p for trend including no CAD=0.012).

The association between monocytes and CAD was most marked among patients with a history of hypercholesterolaemia (monocyte count in CAD vs. no CAD: 0.63 vs. 0.54x109/L, p=0.001), and was absent in those without (0.57 vs 0.56x109/L, p=0.695). In the hypercholesterolaemia subgroup (n=186), a forward conditional logistic regression model including monocyte count alongside traditional risk factors (age, sex, smoking status, diabetes mellitus, hypertension, cholesterol level and family history), showed that only increasing age (p&lt;0.001), male sex (p&lt;0.001) and increasing monocyte count (p=0.01) were independently predictive of CAD.

Conclusion

Raised monocyte count is associated with both the presence and severity of coronary artery disease in patients presenting with anginal symptoms. In patients with a history of hypercholesterolaemia, monocyte count had a more robust predictive ability than many traditional cardiovascular risk factors. Further work is needed to establish whether patients with a relative monocytosis have a higher cardiovascular risk than would be predicted by traditional risk tools.

Funding Acknowledgement

Type of funding sources: None.

Longer leukocyte telomere length is associated with myeloid inflammation and increased mortality after transcatheter aortic valve replacement

Aims

Inflammatory activation of leukocytes may limit prognosis of patients (pts) with severe aortic valve stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR). Leukocyte telomere length (LTL) is a marker of proliferative capacity and inflammatory responsiveness but the impact of LTL on the prognosis in AS remains elusive. The aim of this study was to analyse the association of LTL with inflammatory markers and prognosis of pts undergoing TAVR.

Methods and results

LTL was analysed using quantitative real-time PCR in 285 consecutive pts (median age 82 years) undergoing TAVR and correlated with 18-month all-cause mortality. C-reactive protein was significantly elevated in pts with the longest LTL (P = 0.017), paralleled by increased procalcitonin (PCT) serum levels (P = 0.0006). This inflammatory reaction was accompanied by increased myeloid cells in the highest LTL tertile, mainly a rise in circulating neutrophils (P = 0.0025) and monocytes (P = 0.01). Multivariate analysis revealed LTL (HR 2.6, 95%CI 1.4–5.1,  P= 0.004) and PCT levels (HR 4.3, 95%CI 1.7–11.0, P = 0.003) as independent predictors of mortality.

Conclusions

Longer LTL is associated with increased mortality after TAVR. This might be explained by enhanced proliferative capacity of cells resulting in myeloid and systemic inflammation. Our findings suggest that targeting the specific inflammation pathways could present a novel strategy to augment survival in selected patients with degenerative aortic stenosis.

986 IMMUNOSENESCENCE PROFILES AND MULTIPLE LONG-TERM CONDITIONS IN VERY OLD ADULTS: THE NEWCASTLE 85+ STUDY

Introduction

Immunosenescence, a decline in immune system function, has been linked to several age-related diseases and geriatric syndromes, including cardiovascular diseases and frailty. Very old adults (aged ≥85 years) live with multiple long-term conditions (MLTC) or multimorbidity—a complex phenomenon of poor health defined by either counts (≥2 diseases), indices, or patterns. However, little is known about the relationship between immunosenescence and MLTC in this age group. We utilised baseline data from the Newcastle 85+ Study to investigate the association between previously defined immunosenescence profilesa and MLTC.

Method

We used data from 703 participants who had multimorbidity and complete data for 16 chronic diseases and geriatric syndromes (i.e. analytic sample). MLTC counts were derived from the number of conditions and categorised into &lt;median and ≥ median MLTC groups. We used the SPSS Two Step clustering with all 16 conditions to define MLTC patterns. Two immunosenescence profiles (‘Senescent-like phenotype’ and ‘Less senescent-like phenotype’) were defined previously from 13 lymphocyte compartments. We used multivariable regression analyses to investigate the association between immunosenescence profiles and MLTC counts, groups, and patterns.

Results

In the analytic sample only 6.8% participants had 2 conditions, whilst 79.1% had 3–7, and 14.1% had ≥8 conditions, a median of 5, and 62.2% were in ≥median MLTC group. Three distinct MLTC patterns emerged by clustering: ‘Low cardio-cerebro-metabolic diseases’ (n = 209), ‘High geriatric syndromes-arthritis’ (n = 240), and ‘Hypertensive-renal impairment’ pattern, (n = 254). Having ‘Senescent-like phenotype’ characterised by higher frequency of CD4 and CD8 senescence-like effector memory cells and lower CD4/CD8 ratio was not significantly associated with either MLTC counts, ≥median MLTC group, or patterns compared with ‘Less senescent phenotype’.

Conclusion

No cross-sectional associations between immunosenescence and MLTC were found in the very old. Further studies are needed to determine whether immunosenescence drives change in MLTC counts and patterns and influences MLTC burden in late adulthood.

Clinical frailty, and not features of acute infection, is associated with late mortality in COVID-19: a retrospective cohort study

BACKGROUND

Coronavirus disease 2019 (COVID-19) is associated with excess mortality after hospital discharge. Identification of patients at increased risk of death following hospital discharge is needed to guide clinical monitoring and early intervention. Herein, we aimed to identify predictors of early vs. late mortality in COVID-19 patients.

METHODS

A total of 471 patients with polymerase chain reaction-confirmed COVID-19 were followed up for 9 months [median (inter-quartile range) of follow-up time: 271 (14) days] after hospital admission. COVID-19-related signs and symptoms, laboratory features, co-morbidities, Coronavirus Clinical Characterisation Consortium (4C) mortality and Clinical Frailty Scale (CFS) scores were analysed by logistic regression for association with early (28 day) vs. late mortality. Receiver operating characteristic (ROC) analysis was used to determine the discriminative value of 4C and CFS scores for early vs. late mortality.

RESULTS

A total of 120 patients died within 28 days from hospital admission. Of the remaining 351 patients, 41 died within the next 8 months. Respiratory failure, systemic inflammation, and renal impairment were associated with early mortality, while active cancer and dementia were associated with late mortality, after adjustment for age and sex. 4C mortality score and CFS were associated with both early [odds ratio (OR) (95% confidence interval-CI): 4C: 1.34 (1.25-1.45); CFS: 1.49 (1.33-1.66)] and late [OR (95% CI): 4C: 1.23 (1.12-1.36); CFS: 2.04 (1.62-2.56)] mortality. After adjustment for CFS, the association between 4C and late mortality was lost. By ROC analysis, 4C mortality score was superior to CFS for 28 day mortality [area under the curve (AUC) (95% CI): 0.779 (0.732-0.825) vs. 0.723 (0.673-0.773), respectively; P = 0.039]. In contrast, CFS had higher predictive value for late mortality compared with 4C mortality score [AUC (95% CI): 0.830 (0.776-0.883) vs. 0.724 (0.650-0.798), respectively; P = 0.007].

CONCLUSIONS

In our cohort, late mortality in COVID-19 patients is more strongly associated with premorbid clinical frailty than with severity of the acute infection phase.

Prognostic value of admission high-sensitivity troponin in patients with ST-elevation myocardial infarction

BACKGROUND AND AIM

Although the diagnostic usefulness of high-sensitivity cardiac troponin T (hs-cTnT) is well established in ST-segment elevation myocardial infarction (STEMI), its prognostic relevance in risk stratification of patients with STEMI remains obscure. This study sought to determine the prognostic value of pre-reperfusion (admission) and post-reperfusion (12-hour) hs-cTnT in patients with STEMI treated with primary percutaneous coronary intervention (PPCI).

METHODS

Retrospective observational longitudinal study including consecutive patients with STEMI treated with PPCI at a university hospital in the northeast of England. hs-cTnT was measured at admission to the catheterisation laboratory and 12 hours after PPCI. Clinical, procedural and laboratory data were prospectively collected during patient hospitalisation (June 2010-December 2014). Mortality data were obtained from the UK Office of National Statistics. The study endpoints were in-hospital and overall mortality.

RESULTS

A total of 3113 patients were included. Median follow-up was 53 months. Admission hs-cTnT >515 ng/L (fourth quartile) was independently associated with in-hospital mortality (HR=2.53 per highest to lower quartiles; 95% CI: 1.32 to 4.85; p=0.005) after multivariable adjustment for a clinical model of mortality prediction. Likewise, admission hs-cTnT >515 ng/L independently predicted overall mortality (HR=1.27 per highest to lower quartiles; 95% CI: 1.02 to 1.59; p=0.029). Admission hs-cTnT correctly reclassified risk for in-hospital death (net reclassification index (NRI)=0.588, p<0.001) and overall mortality (NRI=0.178, p=0.001). Conversely, 12-hour hs-cTnT was not independently associated with mortality.

CONCLUSION

Admission, but not 12-hour post-reperfusion, hs-cTnT predicts mortality and improves risk stratification in the PPCI era. These results support a prognostic role for admission hs-cTnT while challenge the cost-effectiveness of routine 12-hour hs-cTnT measurements in patients with STEMI.

Immobilization of Molecularly Imprinted Polymer Nanoparticles onto Surfaces Using Different Strategies: Evaluating the Influence of the Functionalized Interface on the Performance of a Thermal Assay for the Detection of the Cardiac Biomarker Troponin I

We demonstrate that a novel functionalized interface, where molecularly imprinted polymer nanoparticles (nanoMIPs) are attached to screen-printed graphite electrodes (SPEs), can be utilized for the thermal detection of the cardiac biomarker troponin I (cTnI). The ultrasensitive detection of the unique protein cTnI can be utilized for the early diagnosis of myocardial infraction (i.e., heart attacks), resulting in considerably lower patient mortality and morbidity. Our developed platform presents an innovative route to develop accurate, low-cost, and disposable sensors for the diagnosis of cardiovascular diseases, specifically myocardial infraction. A reproducible and advantageous solid-phase approach was utilized to synthesize high-affinity nanoMIPs (average size = 71 nm) for cTnI, which served as synthetic receptors in a thermal sensing platform. To assess the performance and commercial potential of the sensor platform, various approaches were used to immobilize nanoMIPs onto thermocouples or SPEs: dip coating, drop casting, and a covalent approach relying on electrografting with an organic coupling reaction. Characterization of the nanoMIP-functionalized surfaces was performed with electrochemical impedance spectroscopy, atomic force microscopy, and scanning electron microscopy. Measurements from an in-house designed thermal setup revealed that covalent functionalization of nanoMIPs onto SPEs led to the most reproducible sensing capabilities. The proof of application was provided by measuring buffered solutions spiked with cTnI, which demonstrated that through monitoring changes in heat transfer at the solid-liquid interface, we can measure concentrations as low as 10 pg L^-1, resulting in the most sensitive test of this type. Furthermore, preliminary data are presented for a prototype platform, which can detect cTnI with shorter measurement times and smaller sample volumes. The excellent sensor performance, versatility of the nanoMIPs, and reproducible and low-cost nature of the SPEs demonstrate that this sensor platform technology has a clear commercial route with high potential to contribute to sustainable healthcare.

The Fractalkine Receptor CX3CR1 Links Lymphocyte Kinetics in CMV-Seropositive Patients and Acute Myocardial Infarction With Adverse Left Ventricular Remodeling

Aims

Latent cytomegalovirus (CMV) infection is associated with adverse cardiovascular outcomes. Virus-specific CX3CR1+ effector memory T-cells may be instrumental in this process due to their pro-inflammatory properties. We investigated the role of CX3CR1 (fractalkine receptor) in CMV-related lymphocyte kinetics and cardiac remodeling in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (pPCI).

Methods and Results

We retrospectively analysed lymphocyte count, troponin, and survival in 4874 STEMI/pPCI patients, evaluated lymphocyte kinetics during reperfusion in a prospective cohort, and obtained sequential cardiac MRI (cMRI) to assess remodeling. Pre-reperfusion lymphopenia independently predicted mortality at 7.5 years. Prior to reperfusion, CCR7+ T-lymphocytes appeared to be depleted. After reperfusion, T-lymphocytes expressing CX3CR1 were depleted predominantly in CMV-seropositive patients. During ischaemia/reperfusion, a drop in CX3CR1+ T-lymphocytes was significantly linked with microvascular obstruction in CMV+ patients, suggesting increased fractalkine-receptor interaction. At 12 weeks, CMV+ patients displayed adverse LV remodeling.

Conclusion

We show that lymphopenia occurs before and after reperfusion in STEMI by different mechanisms and predicts long-term outcome. In CMV+ patients, increased fractalkine induction and sequestration of CX3CR1+ T-cells may contribute to adverse remodeling, suggesting a pro-inflammatory pathomechanism which presents a novel therapeutic target.

Rapid fall in circulating non-classical monocytes in ST elevation myocardial infarction patients correlates with cardiac injury

Myocardial infarction leads to a rapid innate immune response that is ultimately required for repair of damaged heart tissue. We therefore examined circulating monocyte dynamics immediately after reperfusion of the culprit coronary vessel in STEMI patients to determine whether this correlated with level of cardiac injury. A mouse model of cardiac ischemia/reperfusion injury was subsequently used to establish the degree of monocyte margination to the coronary vasculature that could potentially contribute to the drop in circulating monocytes. We retrospectively analyzed blood samples from 51 STEMI patients to assess the number of non-classical (NC), classical, and intermediate monocytes immediately following primary percutaneous coronary intervention. Classical and intermediate monocytes showed minimal change. On the other hand, circulating numbers of NC monocytes fell by approximately 50% at 90 minutes post-reperfusion. This rapid decrease in NC monocytes was greatest in patients with the largest infarct size (P < .05) and correlated inversely with left ventricular function (r = 0.41, P = .04). The early fall in NC monocytes post-reperfusion was confirmed in a second prospective study of 13 STEMI patients. Furthermore, in a mouse cardiac ischemia model, there was significant monocyte adhesion to coronary vessel endothelium at 2 hours post-reperfusion pointing to a specific and rapid vessel margination response to cardiac injury. In conclusion, rapid depletion of NC monocytes from the circulation in STEMI patients following coronary artery reperfusion correlates with the level of acute cardiac injury and involves rapid margination to the coronary vasculature.

Terminally Differentiated CD4+ T Cells Promote Myocardial Inflammaging

The cardiovascular and immune systems undergo profound and intertwined alterations with aging. Recent studies have reported that an accumulation of memory and terminally differentiated T cells in elderly subjects can fuel myocardial aging and boost the progression of heart diseases. Nevertheless, it remains unclear whether the immunological senescence profile is sufficient to cause age-related cardiac deterioration or merely acts as an amplifier of previous tissue-intrinsic damage. Herein, we sought to decompose the causality in this cardio-immune crosstalk by studying young mice harboring a senescent-like expanded CD4+ T cell compartment. Thus, immunodeficient NSG-DR1 mice expressing HLA-DRB1*01:01 were transplanted with human CD4+ T cells purified from matching donors that rapidly engrafted and expanded in the recipients without causing xenograft reactions. In the donor subjects, the CD4+ T cell compartment was primarily composed of naïve cells defined as CCR7+CD45RO-. However, when transplanted into young lymphocyte-deficient mice, CD4+ T cells underwent homeostatic expansion, upregulated expression of PD-1 receptor and strongly shifted towards effector/memory (CCR7- CD45RO+) and terminally-differentiated phenotypes (CCR7-CD45RO-), as typically seen in elderly. Differentiated CD4+ T cells also infiltrated the myocardium of recipient mice at comparable levels to what is observed during physiological aging. In addition, young mice harboring an expanded CD4+ T cell compartment showed increased numbers of infiltrating monocytes, macrophages and dendritic cells in the heart. Bulk mRNA sequencing analyses further confirmed that expanding T-cells promote myocardial inflammaging, marked by a distinct age-related transcriptomic signature. Altogether, these data indicate that exaggerated CD4+ T-cell expansion and differentiation, a hallmark of the aging immune system, is sufficient to promote myocardial alterations compatible with inflammaging in juvenile healthy mice.

Telomerase as a Therapeutic Target in Cardiovascular Disease

Shortened telomeres have been linked to numerous chronic diseases, most importantly coronary artery disease, but the underlying mechanisms remain ill defined. Loss-of-function mutations and deletions in telomerase both accelerate telomere shortening but do not necessarily lead to a clinical phenotype associated with atherosclerosis, questioning the causal role of telomere length in cardiac pathology. The differential extranuclear functions of the 2 main components of telomerase, telomerase reverse transcriptase and telomerase RNA component, offer important clues about the complex relationship between telomere length and cardiovascular pathology. In this review, we critically discuss relevant preclinical models, genetic disorders, and clinical studies to elucidate the impact of telomerase in cardiovascular disease and its potential role as a therapeutic target. We suggest that the antioxidative function of mitochondrial telomerase reverse transcriptase might be atheroprotective, making it a potential target for clinical trials. Graphic Abstract: A graphic abstract is available for this article.

Involvement of cardiovascular system as the critical point in coronavirus disease 2019 (COVID-19) prognosis and recovery

The novel coronavirus disease 2019 (COVID-19) pandemic has already caused more than 300,000 deaths worldwide. Several studies have elucidated the central role of cardiovascular complications in the disease course. Herein, we provide a concise review of current knowledge regarding the involvement of cardiovascular system in the pathogenesis and prognosis of COVID-19. We summarize data from 21 studies involving in total more than 21,000 patients from Asia, Europe, and the USA indicating that severe disease is associated with the presence of myocardial injury, heart failure, and arrhythmias. Additionally, we present the clinical and laboratory differences between recovered and deceased patients highlighting the importance of cardiac manifestations. For the infected patients, underlying cardiovascular comorbidities and particularly existing cardiovascular disease seem to predispose to the development of cardiovascular complications, which are in turn associated with higher mortality rates. We provide mechanistic insights into the underlying mechanisms including direct myocardial damage by the virus and the consequences of the hyperinflammatory syndrome developed later in the disease course. Finally, we summarize current knowledge on therapeutic modalities and recommendations by scientific societies and experts regarding the cardiovascular management of patients with COVID-19.

Role of CMV-serostatus and CX3CR1 on lymphocyte kinetics and left ventricular remodelling in patients with acute myocardial infarction

Background

Patients with latent cytomegalovirus (CMV) infection have higher rates of adverse cardiovascular outcomes, but the reasons for this remain elusive. CMV-induced changes to T-lymphocyte populations, with a proliferation of CMV-specific, CX3CR1+ effector memory cells, may contribute. Effector T-cells are associated with cardiovascular mortality in CMV positive patients, and ischaemia-reperfusion injury after ST-elevation myocardial infarction (STEMI) and primary percutaneous coronary intervention (pPCI).

Purpose

To investigate the effect of CMV status on lymphocyte kinetics and cardiac MRI (cMRI) parameters in 52 STEMI patients receiving pPCI, and examine the prognostic relevance of pre-reperfusion lymphocyte count in a large cohort.

Methods

We retrospectively analysed the association between pre-reperfusion lymphocyte count, troponin, and long-term survival in 4874 consecutive STEMI patients. Using flow cytometry, we analysed lymphocyte kinetics in 52 STEMI patients, of known CMV status, during and after pPCI. We assessed the impact of CMV status on infarct size, left-ventricular (LV) function and microvascular obstruction with cMRI in the first week after reperfusion in 101 patients. Repeat cMRI at 12 weeks, to assess LV remodelling, was obtained in 48 patients.

Results

Pre-reperfusion lymphopenia is an independent predictor of mortality over 7.5 years (hazard ratio for lowest vs highest quartile: 2.0; 95% CI 1.7–2.4; p&lt;0.001), and is associated with higher admission troponins (p&lt;0.001 for lowest vs second-lowest quartile), suggesting lymphocyte count falls prior to reperfusion in response to myocardial injury. CMV positive patients had more cytotoxic T-cells, strongly expressing the fractalkine receptor, CX3CR1. In CMV positive patients these cells fell dramatically by 90 minutes post-reperfusion, and dropped more sharply in patients with extensive microvascular obstruction on cMRI (p≤0.05 in all effector subsets). CX3CR1 expression was lower at 90 minutes post-reperfusion than at 24 hours (return to physiological expression) in all effector T-cell subsets. All subsets lost a similar proportion of their 24-hour value, but consistently lost a larger proportion in CMV positive patients (−27% in CMV+, −18% in CMV−; p=0.007). CX3CR1 expression falls in the presence of fractalkine, and we hypothesise that membrane-bound fractalkine is induced more strongly in CMV positive patients, as soluble fractalkine levels were similar. At 12 weeks, LV remodeling was worse in CMV positive patients (change in end-diastolic volume: +10.7ml vs −6.1ml; p=0.02).

Conclusions

Lymphopenia occurs prior to reperfusion in STEMI, and predicts long-term mortality. Effector T-cells drop substantially after reperfusion only in CMV positive patients, likely mediated by CX3CR1-fractalkine interaction, and this is associated with adverse cMRI findings. Remodeling is worse in CMV positive patients at 12 weeks post-STEMI.

Lymphocytes, troponin and survival

Funding Acknowledgement

Type of funding source: Public Institution(s)

Prognostic and reclassification value of serum cathepsin S over the GRACE risk score in patients with non-ST-segment elevation acute coronary syndrome

Background

Cathepsin S is an extracellular matrix degradation enzyme that plays an important role in atherosclerotic cardiovascular disease by inducing vasa vasorum development and atherosclerotic plaque rupture.

Purpose

To determine the prognostic and reclassification value of baseline serum cathepsin S after adjustment for the Global Registry of Acute Coronary Events (GRACE) score, which is a clinical guideline recommended risk score in non-ST-segment elevation acute coronary syndrome (NSTE-ACS).

Methods

Serum cathepsin S was measured by ELISA in 1,129 consecutive patients presenting with acute symptoms to the emergency department for whom a final adjudicated diagnosis of NSTE-ACS was made. All-cause mortality or all-cause death/non-fatal myocardial infarction (MI) after a median follow-up of 21 months were evaluated as the primary or secondary study endpoint, respectively. The Net Reclassification Index (NRI) estimated the reclassification predictive value for risk of each end-point of cathepsin S over the GRACE score.

Results

After a median follow-up of 21 months 101 (8.95%) deaths were reported. The combined endpoint of death or non-fatal MI occurred in 176 (15.6%) patients. Dose-response curve analysis adjusted for the effect of age, gender, diabetes mellitus, high-sensitivity-cardiac troponin T, high-sensitivity C-reactive protein, revascularization and index diagnosis revealed a non-linear association of continuous cathepsin S with all-cause death (P=0.036 for non-linearity; adjusted HR=1.60 for 80th vs. 20th percentiles, P=0.038) or with the combined endpoint (P=0.008 for non-linearity, adjusted HR=1.53 for 80th vs. 20th percentiles, P=0.011). Serum cathepsin S maintained its predictive value for all-cause death (adjusted HR=1.70 highest vs. lowest tertile, 95% CI 1.03–2.82, P=0.039) after adjusting for the GRACE Score. Similarly, cathepsin S predicted the combined endpoint of all-cause death or non-fatal MI (adjusted HR=1.67 highest vs. lowest tertile, 95% CI 1.15–2.42, P=0.007) independently of the GRACE Score. When cathepsin S was added over the GRACE Score it correctly reclassified risk for all-cause death in 20% of the population (P=0.004). Similarly, serum Cathepsin S conferred a significant reclassification value over the GRACE score for all-cause death or non-fatal MI in 15.9% of the population.

Conclusions

Serum cathepsin S is a predictor of mortality and improves risk stratification over the GRACE score in patients with NSTE-ACS. The clinical application of cathepsin S as a novel biomarker in NSTE-ACS should be further explored and validated.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): German Heart Foundation

Interferon-gamma inducible protein IP-10 and left ventricular remodelling post-acute myocardial infarction: a longitudinal cardiovascular magnetic resonance imaging substudy of CAPRI clinical trial

Background

Adverse left ventricular (LV) remodelling is associated with development of heart failure and poor outcomes in patients with acute myocardial infarction (AMI). Understanding the immunomodulatory mechanisms of LV remodelling is an essential step for the development of novel therapies. Interferon-γ-inducible protein-10 (IP-10)/CXCL10 is a chemokine involved in the recruitment of activated T cells into sites of tissue inflammation. Although IP-10 was reported to reduce adverse LV remodeling in a preclinical myocardial infarction model, its role in LV remodeling in humans with AMI remains unknown.

Purpose

To determine the clinical predictive value of serum IP-10 in LV remodeling in patients with ST-segment elevation myocardial infarction (STEMI).

Methods

This is a substudy of the double-blind, randomised controlled trial “Evaluating the effectiveness of intravenous ciclosporin on reducing reperfusion injury in patients undergoing primary percutaneous coronary intervention” (CAPRI; ClinicalTrials.gov registry number NCT02390674), which enrolled 52 acute STEMI patients. LV remodeling was assessed by cardiovascular magnetic resonance (CMR) imaging and was defined as the 12-week vs. the 3-day post-myocardial infarction change of the left ventricular ejection fraction (ΔLVEF), LV end-diastolic volume (ΔEDV) or LV end-systolic volume (ΔESV). Serum IP-10 was measured before and 5min, 15min, 30min, 90min and 24h after reperfusion by ELISA. Linear regression analysis was used to determine the independent association of IP-10 with the endpoints of the study.

Results

Serum IP-10 concentration peaked at 30min after reperfusion followed by a 2-fold decrease at the 24h post reperfusion compared to pre-reperfusion levels (P&lt;0.001 for all). Comparison of the 12-week CMR to the baseline CMR imaging revealed that baseline pre-reperfusion as well as 5min, 15min, 30min and 90min, but not 24h, post-reperfusion IP-10 serum levels associated with increased LVEF and decreased ESV at 12-weeks (range correlation coefficient r=[0.35–0.41], P&lt;0.05 with ΔLVEF and r=[−0.33 to −0.44], P&lt;0.05 with ΔESV) indicating that the increase of IP-10 at the acute phase of myocardial infarction confers a cardioprotective role. Multivariable linear regression analysis for ΔLVEF showed that in a model including baseline pre-reperfusion or 5min or 15min or 30min or 90min post-reperfusion IP-10 and age, gender, traditional risk factors (arterial hypertension, body-mass index, hyperlipoproteinemia, diabetes mellitus, smoking, family history of CAD), infarct location, admission high-sensitivity troponin T, door-to-balloon time and ciclosporin treatment, only IP-10 was the independent determinant of ΔLVEF.

Conclusions

Increased serum IP-10 levels early after reperfusion are associated with reverse LV remodeling in patients with STEMI undergoing primary PCI. The clinical application of IP-10 as a novel biomarker of LV remodeling post-AMI should be further explored and validated.

Funding Acknowledgement

Type of funding source: None

Long telomere length in circulating leukocytes is associated with monocytosis and poorer survival in patients with transcatheter aortic valve replacement

Background

Whiletranscatheter aortic valve replacement (TAVR) has become a standard treatment option in the management of patients with severe aortic stenosis and higher risk for cardiac surgery, occurrence of a systemic inflammatory response after TAVR limits patients' prognosis. Leukocyte telomere length (LTL) is an established marker of cellular senescence and longer telomeres are hallmarks of immune competence and inflammatory responsiveness of leukocyte subsets. In the present study, we assessed LTL and its impact on 2-year survival in patients (pts) following TAVR.

Methods and results

LTL was analyzed using quantitative real-time PCR in 285 consecutive pts (mean age 80.9 years, 49% male) undergoing TAVR and correlated with 2-year all-cause mortality (46 deaths, 16%). Kaplan-Meier survival curves showed that the highest compared to lowest tertile of LTL was associated with an increased rate of all-cause mortality (log rank p=0.03). Multivariate regression model revealed higher EuroSCORE 2 (HR: 1.03, 95% CI: 1.01–1.05; p=0.021) and long LTL (HR: 1.001, 95% CI: 1.001–1.001; p=0.023) to be independent predictors for 2-year mortality, after adjustment for clinical variables such as age, sex, cardiovascular risk factors, LVEF and renal function. When analyzing blood leukocyte subset composition, pts in the highest LTL tertile showed significantly higher levels of circulating neutrophils (p=0.011) and monocytes (p=0.011), whereas there was no significant correlation between LTL and lymphocyte counts (p=0.12).

Conclusion

In elderly patients with severe aortic valve stenosis, long leukocyte telomere length is associated with increased mortality after TAVR. This might be explained by enhanced immune competence and increased pro-inflammatory leukocyte function in these patients as indicated by significant monocytosis, which might drive systemic inflammatory response syndrome or chronic inflammation and limit the prognosis in TAVR patients.

Funding Acknowledgement

Type of funding source: None

Regulation and role of arginine vasopressin in myocardial infarction/reperfusion

Background

Little attention is paid to the coronary microvasculature when treating acute myocardial infarction (MI). Microvascular obstruction contributes to ischaemia-reperfusion (I-R) injury. One proposed mechanism is a persistent vasoconstrictor tone during MI/reperfusion. Arginine vasopressin (AVP) has a vasoactive effect on the coronary microvessels. Moreover, cardiac AVP synthesis was found in an animal model. To exert vasoconstriction, AVP binds to its receptor 1a (AVPR1a).

Aims

(i) To analyse the AVP levels during MI/reperfusion (ii) To assess cardiac AVP and AVPR1a expressions in MI/reperfusion mouse models.

Methods

We took arterial blood samples from ST elevation MI (STEMI) patients admitted to our hospital over the course of MI/reperfusion for AVP levels quantification. We also measured AVP through its more stable surrogate biomarker, copeptin. Cardiac MRI was done to evaluate coronary microvasculature, infarct size, and left ventricular ejection fraction (LVEF) 1 week post-admission. Cardiac AVP and AVPR1a expressions were assessed by polymerase chain reaction (PCR) in mouse models.

Results

STEMI patients displayed bothAVPand copeptinlevels elevation at baseline (130.8±20.5 pmol/l, n=23) until 90 min post-reperfusion (55.7±6.2 pmol/l, n=23). Their concentrations began to approach normal levels at 24h. Patients with poorer reperfusion outcomes had copeptin concentrations that remained above normal level after 24h following reperfusion. Copeptin levels at 24h post-reperfusion were significantly higher in patients who developed larger infarct size (p=0.004) and lower LVEF (p=0.009). Patients with microvascular obstruction tended to have higher copeptin levels from admission until 24h post-reperfusion. Mouse models showed no cardiac AVP expression but significantly high AVPR1a expression at 2h post-reperfusion.

Conclusion

In STEMI patients, circulating AVP level is elevated over the course of MI/reperfusion. In MI/reperfusion mouse models, cardiac AVP synthesis is absent but cardiac AVPR1a is upregulated. The combination of delayed decline in AVP concentrations and AVPR1a upregulation may increase the possibility for AVP to mediate I-R injury through microvascular disturbance. Increased AVP levels at 24h post-reperfusion are significantly associated with poor reperfusion outcome. These results warrant further studies concerning the use of AVP receptor antagonist in STEMI patients undergoing reperfusion therapy

Copeptin levels and reperfusion outcomes

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Newcastle University MRes Programme

Clearance of senescent cells during cardiac ischemia-reperfusion injury improves recovery

A key component of cardiac ischemia-reperfusion injury (IRI) is the increased generation of reactive oxygen species, leading to enhanced inflammation and tissue dysfunction in patients following intervention for myocardial infarction. In this study, we hypothesized that oxidative stress, due to ischemia-reperfusion, induces senescence which contributes to the pathophysiology of cardiac IRI. We demonstrate that IRI induces cellular senescence in both cardiomyocytes and interstitial cell populations and treatment with the senolytic drug navitoclax after ischemia-reperfusion improves left ventricular function, increases myocardial vascularization, and decreases scar size. SWATH-MS-based proteomics revealed that biological processes associated with fibrosis and inflammation that were increased following ischemia-reperfusion were attenuated upon senescent cell clearance. Furthermore, navitoclax treatment reduced the expression of pro-inflammatory, profibrotic, and anti-angiogenic cytokines, including interferon gamma-induced protein-10, TGF-β3, interleukin-11, interleukin-16, and fractalkine. Our study provides proof-of-concept evidence that cellular senescence contributes to impaired heart function and adverse remodeling following cardiac ischemia-reperfusion. We also establish that post-IRI the SASP plays a considerable role in the inflammatory response. Subsequently, senolytic treatment, at a clinically feasible time-point, attenuates multiple components of this response and improves clinically important parameters. Thus, cellular senescence represents a potential novel therapeutic avenue to improve patient outcomes following cardiac ischemia-reperfusion.

Telomerase Activation to Reverse Immunosenescence in Elderly Patients With Acute Coronary Syndrome: Protocol for a Randomized Pilot Trial

Background

Inflammation plays a key role in the pathophysiology of coronary heart disease (CHD) and its acute manifestation, acute coronary syndrome (ACS). Aging is associated with a decline of the immune system, a process known as immunosenescence. This is characterized by an increase in highly proinflammatory T cells that are involved in CHD progression, plaque destabilization, and myocardial ischemia–reperfusion injury. Telomere dysfunction has been implicated in immunosenescence of T lymphocytes. Telomerase is the enzyme responsible for maintaining telomeres during cell divisions. It has a protective effect on cells under oxidative stress and helps regulate flow-mediated dilation in microvasculature.

Objective

The TACTIC (Telomerase ACTivator to reverse Immunosenescence in Acute Coronary Syndrome) trial will investigate whether a telomerase activator, TA-65MD, can reduce the proportion of senescent T cells in patients with ACS with confirmed CHD. It will also assess the effect of TA-65MD on decreasing telomere shortening, reducing oxidative stress, and improving endothelial function.

Methods

The study was designed as a single-center, randomized, double-blind, parallel-group, placebo-controlled phase II trial. Recruitment started in January 2019. A total of 90 patients, aged 65 years or older, with treated ACS who have had CHD confirmed by angiography will be enrolled. They will be randomized to one of two groups: TA-65MD oral therapy (8 mg twice daily) or placebo taken for 12 months. The primary outcome is the effect on immunosenescence determined by a decrease in the proportion of CD8+ TEMRA (T effector memory cells re-expressing CD45RA [CD45 expressing exon A]) cells at 12 months. Secondary outcomes include leukocyte telomere length, endothelial function, cardiac function as measured by echocardiography and NT-proBNP (N-terminal fragment of the prohormone brain-type natriuretic peptide), systemic inflammation, oxidative stress, and telomerase activity.

Results

The study received National Health Service (NHS) ethics approval on August 9, 2018; Medicines and Healthcare products Regulatory Agency approval on October 19, 2018; and NHS Health Research Authority approval on October 22, 2018. The trial began recruiting participants in January 2019 and completed recruitment in March 2020; the trial is due to report results in 2021.

Conclusions

This pilot trial in older patients with CHD will explore outcomes not previously investigated outside in vitro or preclinical models. The robust design ensures that bias has been minimized. Should the results indicate reduced frequency of immunosenescent CD8+ T cells as well as improvements in telomere length and endothelial function, we will plan a larger, multicenter trial in patients to determine if TA-65MD is beneficial in the treatment of CHD in elderly patients.

Trial Registration

ISRCTN Registry ISRCTN16613292; http://www.isrctn.com/ISRCTN16613292 and European Union Drug Regulating Authorities Clinical Trials Database (EudraCT), European Union Clinical Trials Register 2017-002876-26; https://tinyurl.com/y4m2so8g

International Registered Report Identifier (IRRID)

DERR1-10.2196/19456

Immunosenescence profiles are not associated with muscle strength, physical performance and sarcopenia risk in very old adults: The Newcastle 85+ Study

Decline in immune system function (immunosenescence) has been implicated in several age-related disorders. However, little is known about whether alteration in T-cell senescence, a process underlying immunological ageing, is related to muscle health in very old adults (aged ≥85 years). Utilising data from the Newcastle 85+ Study, we aimed to (a) derive and characterise immunosenescence profiles by clustering 13 baseline immunosenescence-related biomarkers of lymphocyte compartments in 657 participants; (b) explore the association between the profiles and 5-year change in muscle strength (grip strength) and physical performance (Timed Up-and-Go test), and (c) determine whether immunosenescence profiles predict 3-year incident sarcopenia. Two distinct clusters were identified; Cluster 1 ('Senescent-like phenotype', n = 421), and Cluster 2 ('Less senescent-like phenotype', n = 236) in individuals with complete biomarker data. Although Cluster 1 was characterised by T-cell senescence (e.g., higher frequency of CD4 and CD8 senescence-like effector memory cells), and elements of the immune risk profile (lower CD4/CD8 ratio, CMV+), it was not associated with change in muscle function over time, or with prevalent or incident sarcopenia. Future studies will determine whether more in-depth characterisation or change in T-cell phenotypes predict the decline in muscle health in late adulthood.

Kinetics Analysis of Circulating MicroRNAs Unveils Markers of Failed Myocardial Reperfusion

BACKGROUND

Failed myocardial reperfusion occurs in approximately 50% of patients with ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PPCI). It manifests as microvascular obstruction (MVO) on cardiac magnetic resonance (CMR) imaging. Although prognostically important, MVO is not routinely screened for. Our aim was to investigate the kinetics of circulating short noncoding ribonucleic acids [microRNAs (miRNAs)] following PPCI and their association with MVO in STEMI patients.

METHODS

Screening of 2083 miRNAs in plasma from STEMI patients with (n = 6) and without (n = 6) MVO was performed by next-generation sequencing. Two candidate miRNAs were selected and quantified at 13 time points within 3 h postreperfusion in 20 STEMI patients by reverse transcription and quantitative PCR. Subsequently, these 2 miRNAs were measured in a "validation" STEMI cohort (n = 50) that had CMR imaging performed at baseline and 3 months post-PPCI to evaluate their association with MVO.

RESULTS

miR-1 and miR-133b were rapidly released following PPCI in a monophasic or biphasic pattern. Both miRNAs were enriched in circulating microparticles. A second miR-1 peak (90-180 min postreperfusion) seemed to be associated with a higher index of microvascular resistance. In addition, miR-1 and miR-133b levels at 90 min post-PPCI were approximately 3-fold (P = 0.001) and 4.4-fold (P = 0.008) higher in patients with MVO, respectively. Finally, miR-1 was significantly increased in a subgroup of patients with worse left ventricular (LV) functional recovery 3 months post-PPCI.

CONCLUSIONS

miR-1 and miR-133b levels increase within 3 h of PPCI. They are positively associated with MVO and worse LV functional recovery post-PPCI.

Effect of Pressure-controlled intermittent Coronary Sinus Occlusion (PiCSO) on infarct size in anterior STEMI: PiCSO in ACS study

•

STEMI patients treated with PiCSO were propensity matched to INFUSE-AMI controls.

•

Infarct size at day 5 was significantly lower in the PiCSO group.

•

There were no major adverse cardiac events (MACE) related to the PiCSO.

Background

The aim of this clinical research was to investigate the effects of Pressure-controlled intermittent Coronary Sinus Occlusion (PiCSO) on infarct size at 5 days after primary percutaneous coronary intervention (pPCI) in patients with ST-segment elevation myocardial infarction (STEMI).

Methods and results

This comparative study was carried out in four UK hospitals. Forty-five patients with anterior STEMI presenting within 12 h of symptom onset received pPCI plus PiCSO (initiated after reperfusion; n = 45) and were compared with a propensity score-matched control cohort from INFUSE-AMI (n = 80). Infarct size (% of LV mass, median [interquartile range]) measured by cardiac magnetic resonance (CMR) at day 5 was significantly lower in the PiCSO group (14.3% [95% CI 9.2–19.4%] vs. 21.2% [95% CI 18.0–24.4%]; p = 0.023). There were no major adverse cardiac events (MACE) related to the PiCSO intervention.

Conclusions

PiCSO, as an adjunct to pPCI, was associated with a lower infarct size at 5 days after anterior STEMI in a propensity score-matched population.

Effect of ciclosporin on safety, lymphocyte kinetics and left ventricular remodelling in acute myocardial infarction

Aims

Following a favourable pilot trial using a single bolus of ciclosporin, it has been unclear why 2 large studies (CYCLE and CIRCUS) failed to prevent reperfusion injury and reduce infarct size in STEMI (ST elevation myocardial infarction). The purpose of this study was to assess the effect of ciclosporin on myocardial injury, left ventricular remodelling and lymphocyte kinetics in patients with acute STEMI undergoing primary percutaneous coronary intervention.

Methods

In this double‐blind, single centre trial, we randomly assigned 52 acute STEMI patients with an onset of pain of <6 hours and blocked culprit artery to a single bolus of ciclosporin (n = 26) or placebo (n = 26, control group) prior to reperfusion by stent percutaneous coronary intervention. The primary endpoint was infarct size at 12 weeks.

Results

Mean infarct size at 12 weeks was identical in both groups (9.1% [standard deviation= 7.0] vs 9.1% [standard deviation = 7.0], P = .99; 95% confidence interval for difference: −4.0 to 4.1). CD3 T‐lymphocytes dropped to similar levels at 90 minutes (867 vs 852 cells/μL, control vs ciclosporin) and increased to 1454 vs 1650 cells/μL at 24 hours.

Conclusion

In our pilot trial, a single ciclosporin bolus did not affect infarct size or left ventricular remodelling, matching the results from CYCLE and CIRCUS. Our study suggests that ciclosporin does either not reach ischaemic cardiomyocytes, or requires earlier application during first medical contact. Finally, 1 bolus of ciclosporin is not sufficient to inhibit CD4 T‐lymphocyte proliferation during remodelling. We therefore believe that further studies are warranted.

(Evaluating the effectiveness of intravenous Ciclosporin on reducing reperfusion injury in pAtients undergoing PRImary percutaneous coronary intervention [CAPRI]; NCT02390674)

CMV-independent increase in CD27-CD28+ CD8+ EMRA T cells is inversely related to mortality in octogenarians

Cytomegalovirus (CMV) seropositivity in adults has been linked to increased cardiovascular disease burden. Phenotypically, CMV infection leads to an inflated CD8 T-lymphocyte compartment. We employed a 8-colour flow cytometric protocol to analyse circulating T cells in 597 octogenarians from the same birth cohort together with NT-proBNP measurements and followed all participants over 7 years. We found that, independent of CMV serostatus, a high number of CD27-CD28+ CD8 EMRA T-lymphocytes (TEMRA) protected from all-cause death after adjusting for known risk factors, such as heart failure, frailty or cancer (Hazard ratio 0.66 for highest vs lowest tertile; confidence interval 0.51-0.86). In addition, CD27-CD28+ CD8 EMRA T-lymphocytes protected from both, non-cardiovascular (hazard ratio 0.59) and cardiovascular death (hazard ratio 0.65). In aged mice treated with the senolytic navitoclax, in which we have previously shown a rejuvenated cardiac phenotype, CD8 effector memory cells are decreased, further indicating that alterations in T cell subpopulations are associated with cardiovascular ageing. Future studies are required to show whether targeting immunosenescence will lead to enhanced life- or healthspan.

5234KAND567, the first selective small molecule CX3CR1 antagonist in clinical development, mediates anti-inflammatory cardioprotective effects in rodent models of atherosclerosis and myocardial infarction

Background

Fractalkine is a chemokine that mediates recruitment and extravasation of CX3CR1-expressing subsets of leukocytes and monocytes and has been implicated in the inflammation-driven pathology of cardiovascular disease. More specifically, fractalkine signaling has been proposed to contribute to increased infarct size and enhanced atherosclerotic plaque vulnerability in patients and experimental models. Blocking fractalkine/CX3CR1 signaling is suggested as a promising anti-inflammatory strategy for the treatment of both acute and chronic cardiovascular disease. KAND567 is a small molecule, selective, non-competitive, allosteric antagonist of the fractalkine receptor CX3CR1, that is under preparation for a clinical phase IIa study in AMI patients.

Purpose

To explore the therapeutic effects of the short and long term administration of KAND567 in experimental rodent models of acute myocardial infarction and atherosclerosis, respectively.

Methods

Myocardial infarction was induced in Wistar rats (N=6–8 per group) by ligation of the left anterior descending (LAD) coronary artery for 30 minutes followed by 2 h of reperfusion. The drug or vehicle infusion started either 5 min before or 30 min after start of reperfusion and continued during the remainder of the experiment. Hearts were collected and subjected to triphenyl tetrazolium chlorine (TTC) staining and the infarction area/area at risk of the left ventricle was determined by planimetry and compared against vehicle group.

Atherosclerosis-prone LDL-receptor deficient mice on a high-cholesterol diet, (N=15–25 per group) were treated with KAND567 for 15–23 weeks. Atherosclerotic plaque development in the thoracic arch was determined by ultrasound imaging and histology. Immunohistochemistry was used to follow changes in the cellular composition in the atherosclerotic lesions.

Results

In the acute myocardial infarction study, the infusion of KAND567 before the start of reperfusion significantly reduced infarcted/risk area (by up to 50%) as compared to the vehicle group. However, the infusion had no effect on the infarct size when administration was initiated 30 min after start of reperfusion.

In the atherogenesis study, oral treatment with KAND567 significantly reduced vascular macrophage infiltration by 50% and reduced intima media thickness. Furthermore, reduced plaque volume and a more stable plaque phenotype was noted following treatment with KAND567.

KAND567 experimental results

Conclusion

Specific inhibition of fractalkine-driven inflammation by KAND567 provides cardioprotective, anti-atherosclerotic and plaque stabilizing effects via mechanisms related to immune cell infiltration, in rodent models. Further studies should be initiated to test if KAND567 is a potential candidate drug, targeting the excessive inflammatory injury associated with ischemia/reperfusion in myocardial infarction and providing plaque stabilization by reducing inflammatory risk for recurrent coronary events.

P4492Peripheral blood mononuclear cell expression of the stabilizing RNA-binding protein HuR is associated with incidence and extent of human atherosclerotic cardiovascular disease

Background

Human Antigen R (HuR) is a stabilizing RNA-binding protein that regulates the expression of several pro-inflammatory molecules. However, its regulation in human atherosclerotic cardiovascular disease remains unknown.

Purpose

To determine the association of peripheral blood mononuclear cell HuR expression with established markers of increased cardiovascular risk and atherosclerosis burden in patients with subclinical or clinically overt coronary artery disease (CAD).

Methods

HuR mRNA expression was measured in peripheral blood mononuclear cells derived from 289 patients with stable CAD or acute myocardial infarction (AMI) and 373 individuals without clinically overt cardiovascular disease (CVD). Structural and functional vascular measurements including intima-media thickness (IMT) and number of atheromatous plaques by carotid and femoral artery ultrasonophaphy, markers of arterial wave reflections by pulse wave analysis and pulse wave velocity were used as surrogate markers of subclinical CVD. The number of angiographically confirmed diseased coronary arteries (>50% stenosis) was used to assess the extent of CAD.

Results

HuR mRNA expression was significantly increased in patients with CAD (both stable and AMI) compared to controls (p=0.039). Subgroup analysis revealed that STEMI patients (n=107) had increased levels of HuR expression compared to NSTEMI (n=49, p=0.03). Among patients with stable CAD (n=133), high HuR expression was independently associated with the number of diseased coronary arteries (OR=1.35 for 1-SD increase in HuR, 95% CI 1.07–1.72, p=0.012), as well as with reduced ejection fraction (EF<45%, OR=1.32 per 1-SD increase, 95% CI 1.05–1.85, p=0.024). Among individuals without CVD, high HuR was associated with lower HDL levels (adjusted beta=-5.2 mg/dl for highest versus lowest quartile, p=0.03) and higher diastolic blood pressure (adjusted beta=3.6 mmHg, p=0.007), while, after adjustment for traditional cardiovascular risk factors, HuR levels in individuals without CVD were independently associated with increased IMT in the common carotid artery (mean increase 6.2% for highest versus lowest quartile, p=0.019).

Conclusion

HuR expression is associated with early subclinical arterial disease in individuals without clinically overt CVD and with the presence and severity of cardiac and vascular dysfunction in patients with clinically overt CAD. These findings imply a clinical role of the HuR pathway in cardiovascular disease and warrant further investigation.

2228Circulating serum extracellular matrix degradation enzyme cathepsin S predicts mortality and improves risk stratification over the GRACE score in patients with non-ST elevation acute coronary syndrom

Background

Blood-based biomarkers may be useful in the identification of residual risk for death or acute myocardial infarction (AMI) in patients with a previous acute coronary syndrome. Cathepsin S (CTSS) is a lysosomal cysteine protease with potent elastolytic and collagenolytic activity, which plays an important role in cardiovascular disease through extracellular matrix degradation, vasa vasorum development and atherosclerotic plaque rupture. The aim of the present study was to determine the prognostic and reclassification value of baseline circulating levels of CTSS after adjustment for the Global Registry of Acute Coronary Events (GRACE) score, which is widely recommended for risk stratification in non-ST-segment elevation acute coronary syndrome (NSTE-ACS).

Methods

CTSS was measured in blood samples collected from 1,129 consecutive patients with adjudicated NSTE-ACS presenting at an acute chest pain unit for evaluation of a possible acute coronary syndrome. Cardiovascular (CV) death and a composite of all-cause mortality and AMI were evaluated as the primary and secondary endpoints of the study, respectively. The additive prognostic value of CTSS over the GRACE score was estimated by the Net Reclassification Index (NRI) that examines the net upward and downward reclassification into correct pre-defined risk categories.

Results

After a median follow-up of 21 months, 101 (8.95%) deaths were reported, of which 63 (5.6%) were of cardiac origin. The combined endpoint occurred in 176 (15.6%) patients. Patients with CTSS in the highest tertile presented the greatest risk for all-cause mortality (HR=1.84 for highest versus lowest tertile of CTSS distribution, 95% CI 1.1–3.08, P=0.02) and CV death (HR=2.5 for highest versus lowest tertile of CTSS distribution, 95% CI 1.24–5.05, P=0.011) after adjustment for age, gender, diabetes mellitus, hs-cTnT, hsCRP, revascularization and index diagnosis. Similarly, CTSS was associated with increased risk of cardiovascular death after adjusting for the GRACE Score (adjusted HR for highest versus lowest tertile of CTSS distribution=2.34, 95% CI 1.18–4.64, P=0.015). Further, CTSS predicted the combined endpoint of all-cause death or non-fatal MI independently of the GRACE Score (adjusted HR for highest versus lowest tertile of CTSS distribution=1.67, 95% CI 1.15–2.42, P=0.007). When CTSS was added over the GRACE Score, it conferred significant reclassification value for CV death (NRI=21.4%, P=0.008). Similarly, CTSS correctly reclassified risk for all-cause death or non-fatal MI (P=0.006) in 15.9% of the population.

Conclusions

Circulating CTSS predicts mortality and improves risk stratification of patients with NSTE-ACS over the GRACE score recommended by clinical guidelines. The clinical application of CTSS as a novel biomarker in NSTE-ACS should be further explored and validated.

The role of arginine vasopressin in myocardial infarction and reperfusion

Little attention is paid to the coronary microvasculature when treating acute myocardial infarction (MI). Microvascular obstruction (MVO) contributes to ischemia-reperfusion injury, which hampers distal blood flow to the myocardium despite recanalization of the culprit epicardial vessel. One of the mechanisms behind reperfusion injury is MVO due to persistent vasoconstrictor tone during reperfusion. Arginine vasopressin (AVP) is a hormone with prominent vasoactive effects on the coronary microvessels. Its levels are elevated as part of a stress response triggered by MI, which was shown to exert vasoconstrictive effects on the coronary arteries in preclinical models, mainly in the nonepicardial vessels of the microcirculation. Circulating AVP levels are up to 100‑fold higher in MI and do not immediately decrease to baseline levels on reperfusion. This results in the so called coronary slow flow phenomenon and mediates ischemia-reperfusion injury. Recently, the C‑terminal fragment of preprovasopressin, copeptin, has emerged as a surrogate biomarker for AVP, as it is more stable in the circulation. Multiple studies have shown the predictive value of both AVP and copeptin with regards to long‑term prognoses of MI patients. We propose that both AVP and copeptin have more than just a predictive value but also play a role in the pathophysiology of adverse outcome post‑MI. Therefore, the treatment of choice for MI should not only focus on the epicardial vessel but also on targeting MVO that might pre‑exist or might directly follow reperfusion. This mandates a clinical trial with an AVP‑receptor antagonist in patients with acute MI undergoing reperfusion therapy.

Pharmacological clearance of senescent cells improves survival and recovery in aged mice following acute myocardial infarction

Cardiovascular disease is the leading cause of death in individuals over 60 years old. Aging is associated with an increased prevalence of coronary artery disease and a poorer prognosis following acute myocardial infarction (MI). With age, senescent cells accumulate in tissues, including the heart, and contribute to age‐related pathologies. However, the role of senescence in recovery following MI has not been investigated. In this study, we demonstrate that treatment of aged mice with the senolytic drug, navitoclax, eliminates senescent cardiomyocytes and attenuates profibrotic protein expression in aged mice. Importantly, clearance of senescent cells improved myocardial remodelling and diastolic function as well as overall survival following MI. These data provide proof‐of‐concept evidence that senescent cells are major contributors to impaired function and increased mortality following MI and that senolytics are a potential new therapeutic avenue for MI.

A comparative analysis of British and American Society of Echocardiography recommendations for the assessment of left ventricular diastolic function

At present there are two recognised guidelines for the echocardiographic assessment of left ventricular diastolic function provided by the British Society of Echocardiography and American Society of Echocardiography/European Association of Cardiovascular Imaging. However, no direct comparison of these guidelines has been performed to establish whether they provide similar diastolic grading. One hundred and eighty-nine consecutive patients in sinus rhythm who underwent transthoracic echocardiography for a primary indication of either heart failure assessment or assessment of left ventricular systolic function were extracted from our database (McKesson Cardiology). Left ventricular diastolic function assessment was performed using both guidelines and the results were compared. Chi-square, Kappa score and one-way ANOVA were used to evaluate the data at a level of P < 0.05. The most frequent outcome was unclassifiable diastolic function with significantly more patients being labelled unclassified with the British compared to American guidelines (47.4 vs 20.5%, P < 0.0001). Having excluded all unclassifiable patients, a significant difference still existed between the two guidelines with a higher proportion of grade one outcomes awarded by the ASE/EACVI guidelines. When grading subcategories were individually compared, there was significantly more grade one diastolic gradings awarded by American compared to the British guidelines (40.7 vs 20.1%, P < 0.0001). In 47% of patients it was not possible to grade diastolic function using the British guidelines, compared to 21% using the American guidelines. For those patients where grading was possible, there was a significant difference in patients classified with normal and grade one diastolic function when using British and American guidelines.