Effects of n-3 Fatty Acid Supplements in Elderly Patients After Myocardial Infarction: A Randomized, Controlled Trial.

BACKGROUND: High intake of marine n-3 polyunsaturated fatty acids (PUFA) has been associated with reduced risk of cardiovascular events; however, this has not been confirmed in patients with a recent acute myocardial infarction (AMI). Elderly patients are at particularly increased cardiovascular risk after myocardial infarction, but few trials address this group specifically. Omega-3 fatty acids hold the potential to reduce cardiovascular events with limited adverse effects in this vulnerable group. The hypothesis was that daily addition of 1.8g n-3 PUFA to standard of care secondary prophylaxis in elderly patients who have survived an AMI would reduce the risk of subsequent cardiovascular events during 2 years follow-up. METHODS: The OMEMI trial (Omega-3 Fatty acids in Elderly with Myocardial Infarction) is an investigator-initiated, multicenter, randomized clinical trial adding 1.8 g n-3 PUFA (930 mg eicosapentaenoic acid and 660 mg docosohexaenoic acid) versus placebo (corn oil) daily to standard of care in patients aged 70 to 82 years with recent (2-8 weeks) AMI. The primary endpoint was a composite of nonfatal AMI, unscheduled revascularization, stroke, all-cause death, heart failure hospitalization after 2 years. The secondary outcome was new atrial fibrillation. The safety outcome was major bleeding. Serum fatty acids were measured as biomarkers of adherence. RESULTS: In total, 1027 patients were randomized. Follow-up data were available for 1014 patients who were included in the intention-to-treat analysis. Mean±SD age was 75±3.6 years, 294 (29%) were female, and mean triglycerides were 111.4±61.9 mg/dL. The primary endpoint occurred in 108 (21.4%) patients on n-3 PUFA versus 102 (20.0%) on placebo (hazard ratio, 1.08 [95% CI, 0.82-1.41]; P=0.60). The secondary endpoint occurred in 28 (7.2%) patients on n-3 PUFA versus 15 (4.0%) on placebo (1.84 [0.98-3.45]; P=0.06). Median changes in eicosapentaenoic acid and docosahexaenoic acid were +87% and +16% for n-3 PUFA versus -13% and -8% for placebo. Major bleeding occurred in 54 (10.7%) and 56 (11.0%) in the n-3 PUFA and placebo groups, respectively (P=0.87). Similar results were found in per-protocol analysis (n=893). CONCLUSIONS: We could not detect reduction in clinical events in our elderly patients with recent AMI who were treated with 1.8 g n-3 PUFAs daily for 2 years. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01841944.

Changes in eicosapentaenoic acid and docosahexaenoic acid and risk of cardiovascular events and atrial fibrillation: A secondary analysis of the OMEMI trial.

BACKGROUND: The cardiovascular benefit from n-3 polyunsaturated fatty acids (PUFAs) after acute myocardial infarction (AMI) is controversial, and the importance of serum eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) concentrations for clinical events is unclear. OBJECTIVES: To assess changes in EPA and DHA serum concentrations during n-3 PUFA supplementation and their association with incident cardiovascular events. METHODS: In the OMEMI trial, elderly patients with a recent AMI were randomized to 1.8 g/day of EPA/DHA or control (corn oil) for 2 years. The primary outcome was a composite of AMI, coronary revascularization, stroke, heart failure hospitalization, or all-cause death (major adverse cardiovascular event [MACE]) and the secondary outcome was new-onset atrial fibrillation (AF). RESULTS: EPA and DHA measurements were available in 881 (92% of survivors) participants at randomization and study completion. EPA and DHA increased in the active treatment arm (n = 438) by a median of 87% and 16%, respectively. Greater on-treatment increases in EPA and DHA were associated with decreasing triglycerides, increasing high-density lipoprotein cholesterol, and lower baseline EPA and DHA concentrations. Greater on-treatment increases in EPA were associated with lower risk of MACE (adjusted hazard ratio 0.86 [95% confidence interval, CI, 0.75-0.99], p = 0.034), and higher risk of AF (adjusted hazard ratio (HR) 1.36 [95% CI 1.07-1.72], p = 0.011). Although there were similar tendencies for DHA changes and outcomes, these associations were not statistically significant (HR 0.84 [0.66-1.06] for MACE and 1.39 [0.90-2.13] for AF). CONCLUSION: Greater on-treatment increases in EPA were associated with lower risk of MACE and higher risk of new-onset AF. These data suggest that the cardiovascular effects of increasing n-3 PUFA levels through supplements are complex, involving both potential benefits and harm.

Gene expression of fibrinolytic markers in coronary thrombi.

BACKGROUND: The fibrinolytic system plays an important role in coronary artery atherothrombosis, and especially circulating plasminogen-activator inhibitor (PAI) type 1 (PAI-1) associates with increased mortality, infarct size and heart failure in patients with myocardial infarction (MI). In a cross-sectional study, we aimed to study whether genes encoding tissue plasminogen activator (tPA), urinary-type plasminogen activator (uPA), PAI-1 and PAI-2 are expressed in coronary thrombi from acute ST-elevation MI (STEMI) patients. Any relations to myocardial injury measured by peak troponin T, time from symptom onset to Percutaneous Coronary Intervention (PCI), and to different cell types present in the thrombi were also explored. METHODS: Intracoronary thrombi were aspirated from 33 STEMI patients treated with primary PCI. The thrombi were snap-frozen for gene expression analyses, relatively quantified by RT PCR. Peripheral blood samples were drawn. Correlations were performed by Spearmans rho. RESULTS: The genes were present in 74-94% of the thrombi. Median peak troponin T was 3434 µ/L and median ischemic time 152 min. There were no significant correlations between the measured genes and troponin T, or ischemic time. Genes encoding tPA, u-PA, PAI-1 and PAI-2 all correlated significantly to the presence of monocytes/macrophages (CD68) in the thrombi (p = 0.028, p < 0.001, p = 0.003, p < 0.001). PAI-1 and PAI-2 also correlated to endothelial cells (CD31) (p = 0.002, p = 0.016). uPA associated with neutrophil granulocytes (CD 66b) (p = 0.019). CONCLUSION: Genes encoding tPA, uPA, PAI-1 and PAI-2 were highly expressed in human coronary thrombi from STEMI patients, indicating fibrinolytic regulators playing active roles in the thrombi, although not related to myocardial injury. All markers related to the presence of monocytes/macrophages, indicating connection to local inflammatory cells. TRIAL REGISTRATION: The study is registered at clinicaltrials.gov with identification number NCT02746822 .

Screen-detected atrial fibrillation and 'micro-atrial fibrillation' and risk of cardiovascular events after myocardial infarction in elderly patients.

BACKGROUND: Incident atrial fibrillation (AF) occurs in 5-10% of patients after acute myocardial infarction (AMI) and is associated with adverse outcomes. Guidelines now recommend screening for AF in all elderly patients. However, the relevance of screen-detected AF and short episodes of irregular supraventricular ectopic beats ('micro-AF') after AMI is unknown. OBJECTIVES: To investigate the value of two-week intermittent ECG screening to detect incident AF and 'micro-AF' in elderly patients 12 months after an AMI, and its association with risk of cardiovascular events. METHODS: This was an investigator-initiated, multicenter substudy of the OMega-3 fatty acids in Elderly patients with Myocardial Infarction (OMEMI) trial, in Norway. Women and men aged 70-82 years, with a recent AMI, were recruited during 2012-2018. All participants had a 12-lead ECG performed at 3, 12 and 24 months. Patients without AF one year after the index AMI underwent 2 weeks of intermittent 30-second 'thumb ECG' screening. Incident AF and 'micro-AF' (episodes of ≥3 consecutive irregular supraventricular ectopic beats) were registered, and the association with risk of major cardiovascular events (MACE; non-fatal AMI, stroke, coronary revascularization, hospitalization for heart failure, or all-cause death) was analyzed with logistic regression. RESULTS: Among 1014 patients (198 (28.7%) women), 255 (25.1%) had known AF or AF identified at baseline. New-onset AF was detected clinically or at study visits in 39 (3.8%) patients. By screening participants without AF (n=567), unknown AF was identified in 4 (0.7%) and 'micro-AF' in 27 (4.8%) patients. Among 43 patients with incident AF, 21 (48.8%) experienced a MACE, which was significantly higher than those without AF (n=114, 15.9%; p<0.001), driven by a higher risk of AMI or revascularization. Nine (33.3%) patients with 'micro-AF' and 75 (13.9%) without 'micro-AF' experienced a MACE (p=0.002), explained mostly by a higher risk of heart failure hospitalization (p<0.001). Using patients without AF and 'micro-AF' as reference, 'micro-AF' was associated with an intermediate risk of MACE (OR 2.8; 95% CI 1.2-6.4) and new-onset AF with a high risk of MACE (OR 5.3; 95% CI 2.8-10.0). CONCLUSIONS: Two-week intermittent ECG screening identified few cases of new-onset AF, but a substantial number of patients with 'micro-AF'. 'Micro-AF' was associated with an increased risk of major cardiovascular events, albeit with an intermediate risk compared to those with new-onset AF.

Exercise-induced change in circulating NT-proBNP could not distinguish between patients with and without coronary artery disease: the CADENCE study.

Objective. In patients with chest pain, exercise stress test has a moderate accuracy for coronary artery disease (CAD). Adding a reliable cardiac biomarker to the exercise test could potentially improve the precision of the test. We investigated circulating NT-proBNP levels before and during exercise stress test in patients with and without angiographically verified CAD. We hypothesized that NT-proBNP would give an additive diagnostic value to the exercise stress test. Methods. In patients presenting with symptoms of stable CAD, venous blood samples were taken at rest and within 5 min of termination of a maximal stress test on a bicycle ergometer. All study participants underwent coronary angiography. Significant CAD was defined as ≥75% stenosis in one or more segments of the coronary arteries. Results. Of the 297 participants, significant CAD was found in 111 (37%) patients. Resting levels of NT-proBNP were significantly higher in patients with CAD compared with patients without CAD (74.18 vs. 56.03 ng/L), p = .005. During exercise, NT-proBNP levels increased in the total population (p < .001). The rise was, however, not significantly different between the two groups (8.24 vs. 8.51 ng/L), p = .700. Combining resting NT-proBNP with positive exercise stress test was superior to exercise test alone in predicting CAD, AUC = 0.68 vs. 0.64. Conclusion. Exercise-induced change in circulating NT-proBNP could not distinguish between patients with or without CAD. However, resting levels of NT-proBNP were significantly higher in patients with CAD than those without CAD.

Biomarkers of ageing and cardiac remodeling are associated with atrial fibrillation.

Objectives. Ageing is one of the strongest risk factors for atrial fibrillation (AF), and additional risk factors are also closely related to ageing. Remodeling is part of the pathophysiology of AF, and a possible common denominator of ageing and other AF risk factors. The aim of this study was to investigate any association between the presence of AF and the ageing biomarkers, leukocyte telomere length (LTL) and sirtuin-1 (SIRT-1), and the cardiac remodeling biomarkers Galectin-3 and sST2 in elderly myocardial infarction (MI) patients. Design. Patients were included after admission for MI. Diagnosis of AF was retrieved from medical records and classified as either history of AF before MI or new onset from admission to study inclusion. SIRT-1, sST2 and Galectin-3 were analyzed by ELISAs and LTL by qPCR. Results. In total, 299 patients were included, median age 75 years, 70.2% male. A history of AF was recorded in 38 patients and 30 patients experienced new onset AF. Higher levels of SIRT-1 were associated with lower risk of having a history of AF (OR = 0.46 (95% CI 0.26, 0.81), p = 0.007), whereas higher sST2 levels were associated with higher risk of AF (OR = 4.13 (95% CI 1.69, 10.13), p = 0.002). Results remained significant after adjustment for other AF risk factors. No significant associations with AF were found for Galectin-3 or LTL. None of the biomarkers associated with new onset AF. Conclusion. In elderly patients with MI, higher ST2 and lower SIRT-2 levels were associated with higher prevalence of AF, possibly reflecting both ageing and the remodeling phenomena in AF. Clinical trials registration: ClinicalTrials.gov (NCT01841944).

The Inflammasome Signaling Pathway Is Actively Regulated and Related to Myocardial Damage in Coronary Thrombi from Patients with STEMI.

BACKGROUND: The Nod-Like-Receptor-Protein-3 (NLRP3) inflammasome and the Interleukin-6 (IL-6) pathways are central mechanisms of the inflammatory response in myocardial reperfusion injury. Expanding our knowledge about the inflammasome signaling axis is important to improve treatment options. In a cross-sectional study, we aimed to study presence, localization, and genetic expression of inflammasome- and IL-6- signaling-related proteins in coronary thrombi and circulating leukocytes from ST-elevation myocardial infarction (STEMI) patients, with relation to myocardial injury and time from symptoms to PCI. METHODS: Intracoronary thrombi were aspirated from 33 STEMI patients. Blood samples were drawn. mRNA of Toll-Like-Receptor-4 (TLR4), NLRP3, caspase 1, Interleukin-1ß (IL1-ß), Interleukin-18 (IL-18), IL-6, IL-6-receptor (IL-6R), and glycoprotein 130 (gp130) were isolated from thrombi and circulating leukocytes and relatively quantified by RT-PCR. A part of each thrombus was embedded in paraffin for histology and immunohistochemistry analyses. RESULTS: Genes encoding the 8 markers were present in 76-100% of thrombi. Expression of TLR4 in thrombi significantly correlated to troponin T (r = 0.455, p = 0.013), as did NLRP3 (r = 0.468, p = 0.024). Troponin T correlated with expression in circulating leukocytes of TLR4 (r = 0.438, p = 0.011), NLRP3 (r = 0.420, p = 0.0149), and IL-1ß (r = 0.394, p = 0.023). IL-6R expression in thrombi correlated significantly to troponin T (r = 0.434, p = 0.019), whereas gp130 was inversely correlated (r = -0.398, p = 0.050). IL-6 in circulating leukocytes correlated inversely to troponin T (r = -0.421, p = 0.015). There were no significant correlations between genes expressed in thrombi and time from symptom to PCI. CONCLUSIONS: The inflammasome signaling pathway was actively regulated in coronary thrombi and in circulating leukocytes from patients with STEMI, in association with myocardial damage measured by troponin T. This supports the strategy of medically targeting this pathway in treating myocardial infarction and contributes to sort out optimal timing and targets for anti-inflammatory treatment. The study is registered at clinicaltrials.gov with identification number NCT02746822.

Procoagulant activity in children and adolescents on intensive insulin therapy.

BACKGROUND: Type 1 diabetes is associated with atherothrombosis, but limited data exist on procoagulant activity in the young. We investigated procoagulant activity in children/adolescents with type 1 diabetes using intensified insulin treatment compared with controls in a 5-year follow-up study, and further any associations with cardiovascular risk factors. METHODS: The study included 314 diabetes children/adolescents and 120 healthy controls. Prothrombin fragment 1+2 (F1+2), D-dimer, tissue-factor-procoagulant-activity (TF-PCA), and tissue-factor-pathway-inhibitor (TFPI) were analyzed with ELISAs. RESULTS: F1+2, D-dimer, and TF-PCA did not differ between the groups or correlate to HbA1c in the diabetes group at either time points. TFPI was significantly higher in the diabetes group compared with controls both at inclusion and follow-up (both P < .001). In the diabetes group, TFPI correlated significantly to HbA1c at both time points (r = 0.221 and 0.304, both P < .001). At follow-up, females using oral contraceptives had significantly elevated F1+2, D-dimer, and TF-PCA and lower TFPI compared to no-users (all P < .005), and females had lower TFPI (P = .017) and higher F1+2 compared with males (P = .052), also after adjusting for the use of oral contraceptives. CONCLUSIONS: The current results show similar procoagulant activity in children/adolescents with type 1 diabetes compared with controls over a 5-year period, indicating that these children using modern intensified insulin treatment are not at high thrombotic risk at younger age. The elevated levels of TFPI in the diabetes group, related to hyperglycaemia, are probably reflecting increased endothelial activation. These findings highlight the significance of optimal blood glucose control in children/adolescents with type 1 diabetes, to maintain a healthy endothelium.

Complement Activation in Association with Markers of Neutrophil Extracellular Traps and Acute Myocardial Infarction in Stable Coronary Artery Disease.

Complement activation and neutrophil extracellular traps (NETs) have both been suggested to drive atherosclerotic plaque progression. Although experimental studies suggest interplay between these two innate immunity components, the relevance in patients with coronary artery disease (CAD) is unclear. The aim of this study was to assess associations between complement activation and NETs in patients with stable CAD and examine the role of complement activation on clinical outcome. Blood samples from a cohort of patients with angiographically verified stable CAD (n = 1001) were analyzed by ELISA for the terminal complement complex (TCC) and by relative quantification for gene expression of the C5a receptor 1 (C5aR1) as markers of complement activation. As markers of NETs, dsDNA was analyzed by fluorescent nucleic acid stain and myeloperoxidase-DNA (MPO-DNA) by ELISA. Clinical outcome was defined as unstable angina, nonhemorrhagic stroke, acute myocardial infarction (MI), or death (n = 106, whereof 36 MI). Levels of TCC and C5aR1 were not significantly correlated to dsDNA (TCC: r = -0.045, p = 0.153; C5aR1: r = -0.060, p = 0.434) or MPO-DNA (TCC: r = 0.026, p = 0.414; C5aR1: r = 0.123, p = 0.107). When dividing TCC and C5aR1 levels into quartiles (Q), levels of MPO-DNA differed significantly across quartiles (TCC: p = 0.008, C5aR1: 0.049), while dsDNA did not (TCC: p = 0.181, C5aR1: p = 0.771). Patients with TCC levels in Q4 had significantly higher levels of MPO-DNA than Q1-3 (p = 0.019), and C5aR1 levels in Q3-4 had significantly higher levels of MPO-DNA than Q1-2 (p = 0.046). TCC levels did not differ between patients experiencing a clinical endpoint or not, but high levels were associated with increased risk of acute MI (OR. 1.97, 95% CI: 0.99-3.90, p = 0.053) during two-year follow up, also when adjusted for relevant covariates. In conclusion, TCC and C5aR1 were moderately associated with the NET marker MPO-DNA, and TCC levels were related to the risk of future MI in this cohort of patients with stable CAD.

A brief review on resistance to P2Y12 receptor antagonism in coronary artery disease.

BACKGROUND: Platelet inhibition is important for patients with coronary artery disease. When dual antiplatelet therapy (DAPT) is required, a P2Y12-antagonist is usually recommended in addition to standard aspirin therapy. The most used P2Y12-antagonists are clopidogrel, prasugrel and ticagrelor. Despite DAPT, some patients experience adverse cardiovascular events, and insufficient platelet inhibition has been suggested as a possible cause. In the present review we have performed a literature search on prevalence, mechanisms and clinical implications of resistance to P2Y12 inhibitors. METHODS: The PubMed database was searched for relevant papers and 11 meta-analyses were included. P2Y12 resistance is measured by stimulating platelets with ADP ex vivo and the most used assays are vasodilator stimulated phosphoprotein (VASP), Multiplate, VerifyNow (VN) and light transmission aggregometry (LTA). DISCUSSION/CONCLUSION: The frequency of high platelet reactivity (HPR) during clopidogrel therapy is predicted to be 30%. Genetic polymorphisms and drug-drug interactions are discussed to explain a significant part of this inter-individual variation. HPR during prasugrel and ticagrelor treatment is estimated to be 3-15% and 0-3%, respectively. This lower frequency is explained by less complicated and more efficient generation of the active metabolite compared to clopidogrel. Meta-analyses do show a positive effect of adjusting standard clopidogrel treatment based on platelet function testing. Despite this, personalized therapy is not recommended because no large-scale RCT have shown any clinical benefit. For patients on prasugrel and ticagrelor, platelet function testing is not recommended due to low occurrence of HPR.

Glucose associated NETosis in patients with ST-elevation myocardial infarction: an observational study.

BACKGROUND: Neutrophil extracellular traps (NETs) have recently been identified as mediators in atherothrombosis. Although NETosis in general has been suggested to be glucose dependent, the transferability to patients with acute ST-elevation myocardial infarction (STEMI) is unclear. We assessed whether the NETs markers double-stranded deoxyribonucleid acid (dsDNA) and myeloperoxidase-DNA (MPO-DNA) associated with plasma glucose and the glucometabolic status in the acute phase and 3 months after a STEMI. We also explored whether an acute glucose load resulted in upregulated NETosis by assessment of peptidylarginine deiminase 4 (PAD4) gene expression. METHODS: In total, 224 STEMI patients were prospectively enrolled and underwent blood sampling acutely (median 16.5 h after PCI) and after 3 months. Glucometabolic status was defined based on the results of an oral glucose tolerance test (OGTT) as normal glucose regulation (NGR), impaired fasting glucose (IFG), impaired glucose tolerance (IGT) or type 2 diabetes (T2DM). dsDNA and MPO-DNA were measured in serum, while PAD4 mRNA was measured in circulating leukocytes by RT-PCR. RESULTS: dsDNA levels were significantly correlated to plasma glucose both acutely and after 3 months (r = 0.12 and r = 0.17, both p < 0.02), whereas MPO-DNA was not. No associations with the glucometabolic status were encountered for dsDNA and MPO-DNA acutely, but after 3 months dsDNA levels were elevated in patients with IFG and T2DM vs. NGR (428 vs. 371 ng/ml and 408 vs. 371 ng/ml, both p < 0.045). During the acute glucose load after 3 months, dsDNA and MPO-DNA remained unchanged while PAD4 mRNA increased significantly (RQ 0.836 vs. 0.920, p = 0.02). CONCLUSIONS: In this cohort of STEMI patients, levels of dsDNA associated with plasma glucose both in the acute and stable condition. The glucometabolic status was not substantially related to the selected NETs markers, however, an acute glucose load by OGTT performed after 3 months resulted in increased PAD4 expression, suggestive of enhanced NETosis in the aftermath of STEMI. TRIAL REGISTRATION: www.clinicaltrials.gov, NCT00926133 . Registered June 23, 2009.

Leukocyte telomere length and serum polyunsaturated fatty acids, dietary habits, cardiovascular risk factors and features of myocardial infarction in elderly patients.

BACKGROUND: Telomeres are non-coding sequences at the end of eukaryote chromosomes, which in complex with associated proteins serve to protect subtelomeric DNA. Telomeres shorten with each cell division, are regarded as a biomarker for aging and have also been suggested to play a role in atherosclerosis and cardiovascular disease (CVD). The aim of the present study was to explore the associations between leukocyte telomere length and serum polyunsaturated fatty acids, diet, cardiovascular risk factors and features of myocardial infarction (MI) in elderly patients. METHODS: The material is based upon the first 299 included patients in the OMEMI trial, where patients aged 70-82 years of age are randomized to receive omega-3 supplements or corn oil (placebo) after MI. Patients were included 2-8 weeks after the index MI. DNA was extracted from whole blood, and leukocyte telomere length (LTL) was analyzed by qPCR and reported as a number relative to a reference gene. Serum long chain polyunsaturated fatty acid (LCPUFA) content was analyzed by gas chromatography. Diet was evaluated with the validated SmartDiet food frequency questionnaire. Medical records, patient interviews and clinical examination provided previous medical history and anthropometric data. Non-parametric statistical tests were used. RESULTS: Median (25, 75 percentile) LTL was 0.55 (0.42, 0.72). Patients had a median age of 75 years, 70.2% were male and 45.2% used omega-3 supplements. There was a weak, but significant correlation between LTL and linoleic acid (r = 0.139, p = 0.017), but not with other LCPUFAs. There was a trend towards longer telomeres with a healthier diet, but this did not reach statistical significance (p = 0.073). No associations were found between LTL and CVD risk factors or features of MI. CONCLUSIONS: In our population of elderly with a recent myocardial infarction LTL was associated with linoleic acid concentrations, but not with other LCPUFAs. Patients with a healthy diet tended to have longer telomeres. The limited associations may be due to age and the narrow age-span in our population. Further studies, designed to detect longitudinal changes should be performed to explore the role of telomeres in cardiovascular aging. TRIAL REGISTRATION: Clinical trials no. NCT01841944, registration date April 29, 2013.

Neutrophil Extracellular Trap Components Associate with Infarct Size, Ventricular Function, and Clinical Outcome in STEMI.

BACKGROUND: The relevance of neutrophil extracellular traps (NETs) in acute ST-elevation myocardial infarction (STEMI) is unclear. We explored the temporal profile of circulating NET markers and their associations to myocardial injury and function and to adverse clinical events in STEMI patients. METHODS AND RESULTS: In 259 patients, blood samples were drawn before and after PCI, on day 1, and after 4 months. Double-stranded deoxyribonucleic acid (dsDNA) and myeloperoxidase-DNA (MPO-DNA) were measured in serum by a nucleic acid stain and ELISA. Cardiac magnetic resonance imaging assessed microvascular obstruction (MVO), area at risk, infarct size, myocardial salvage index, left ventricular ejection fraction (LVEF), and change in indexed left ventricular end-diastolic volume (LVEDVi). Clinical events were registered after 12 months. dsDNA and MPO-DNA levels were highest before PCI, with reduced levels thereafter (all p ≤ 0.02). Patients with high vs. low day 1 dsDNA levels (>median; 366 ng/ml) more frequently had MVO, larger area at risk, larger infarct size acutely and after 4 months, and lower myocardial salvage index (all p < 0.03). Moreover, they had lower LVEF acutely and after 4 months, and larger change in LVEDVi (all p ≤ 0.014). High day 1 dsDNA levels also associated with risk of having a large infarct size (>75th percentile) and low LVEF (≤49%) after 4 months when adjusted for gender, time from symptoms to PCI, and infarct localization (OR 2.3 and 3.0, both p < 0.021), and patients with high day 1 dsDNA levels were more likely to experience an adverse clinical event, also when adjusting for peak troponin T (hazard ratio 5.1, p = 0.012). No such observations were encountered for MPO-DNA. CONCLUSIONS: High day 1 dsDNA levels after STEMI were associated with myocardial infarct size, adverse left ventricular remodeling, and clinical outcome. Although the origin of dsDNA could be discussed, these observations indicate a potential role for dsDNA in acute myocardial ischemia. This trial is registered with S-08421d, 2008/10614 (Regional Committee for Medical Research Ethics in South-East Norway (2008)).

Effect of strenuous exercise on mediators of inflammation in patients with coronary artery disease.

BACKGROUND: Coronary artery disease (CAD) is considered a low-grade inflammatory disease. We aimed to identify effects of short-term strenuous exercise on mediators of systemic inflammation, endothelial and platelet activation in patients with angiographically verified CAD. We hypothesized that a more pronounced inflammatory response would be present in patients with CAD than in those without CAD. METHODS: In subjects with symptoms indicative of stable CAD, an exercise stress test on a bicycle ergometer was performed. Venous blood samples, taken at rest and within 5 min after end of exercise, were analyzed for the following markers by ELISAs: TNF-α, IL-6, MCP-1, ICAM-1, VCAM-1, E-selectin, P-selectin, CD40L and RANTES. All participants underwent conventional coronary angiography. CAD was defined as having any degree of atherosclerosis. RESULTS: A total of 110 patients were included, of whom 74 were found to have CAD. Mean exercise duration was 10:06 ±â€¯3:56 min with no significant difference between the two groups. All measured markers changed significantly during exercise (p ≤ 0.012). A significantly less pronounced increase in CD40L in the CAD group than in the no CAD group was observed (p = 0.050), however, after adjustment for hematocrit this difference was no longer significant. CONCLUSION: An instant inflammatory response was observed during short-term strenuous exercise in patients with symptoms of CAD. However, the exercise mediated response was not more pronounced in patients with CAD.

MMP-9 and Its Regulators TIMP-1 and EMMPRIN in Patients with Acute ST-Elevation Myocardial Infarction: A NORDISTEMI Substudy.

OBJECTIVES: The extracellular matrix is involved in wound repair after acute myocardial infarction (AMI). We investigated whether matrix metalloproteinase (MMP)-9, tissue inhibitor of metalloproteinases (TIMP)-1, and the MMP inducer (EMMPRIN) are associated with infarct size, left ventricular function, and clinical outcome in ST-elevation-MI (STEMI). METHODS: In 243 STEMI patients, circulating EMMPRIN, MMP-9, and TIMP-1 were analyzed 3 days and 3 months post-AMI. Infarct size and left ventricular ejection fraction were assessed by single-photon emission computed tomography (SPECT) (n = 230/226) and MRI (n = 111/167) at 3 months. RESULTS: EMMPRIN, MMP-9, and TIMP-1 levels and the MMP-9/TIMP-1 ratio declined from day 3 to 3 months (p < 0.001, all). TIMP-1 levels at day 3 correlated significantly with SPECT- and MRI-based infarct size, troponin T (p < 0.04, all), and amino-terminal pro-B-type natriuretic peptide (NT-proBNP; p < 0.001). The upper quartile of day 3 TIMP-1 levels showed an adjusted odds ratio of 5.0 (95% confidence interval 1.2-20.6) for having a large infarct size. An insignificant relationship between MMP-9 and clinical events within 1 year (death, AMI, or stroke) (n = 15) was observed, probably due to the lack of statistical power. CONCLUSION: The decline in EMMPRIN, MMP-9, and TIMP-1 3 months after acute STEMI is probably due to initial acute-phase processes. The associations between TIMP-1, infarct size, and NT-proBNP indicate a role for TIMP-1 in cardiac remodeling.

High-sensitivity troponin I in persistent atrial fibrillation - relation to NT-proBNP and markers of inflammation and haemostasis.

PURPOSE: As cardiac troponins emerge as prognostic markers in atrial fibrillation (AF), it is important to identify mechanisms initiating and perpetuating cardiac troponin release, including its relations to other circulating biomarkers, in AF populations. We studied associations between high-sensitivity troponin I (hs-TnI) and markers representing myocardial wall tension, inflammation and haemostasis in persistent AF. METHODS: In a double blind, placebo-controlled study, 171 patients referred for electrical cardioversion for persistent AF were randomised to receive candesartan or placebo for 3-6 weeks before and 6 months after cardioversion. Associations between baseline levels of hs-TnI and other biomarkers were investigated by bivariate non-parametric correlations (Spearman's correlation coefficient denoted rs). RESULTS: Baseline levels of hs-TnI correlated significantly, although weakly, with interleukin-6 (rs = 0.260, p = .003), N-terminal pro-B-type natriuretic peptide (rs = 0.251, p = .004), tissue-plasminogen activator antigen (rs = 0.233, p = .008), D-dimer (rs = 0.220, p = .013), E-selectin (rs = 0.207, p = .019), high-sensitivity C-reactive protein (rs = 0.202, p = .022) and vascular cell adhesion molecule-1 (rs = 0.189, p = .032). CONCLUSIONS: Hs-TnI correlated weakly with biomarkers representing myocardial wall tension, inflammation and haemostasis in persistent AF. The lack of any strong correlation between hs-TnI and the investigated biomarkers is in concert with the idea that hs-TnI release is an independent process parallel to other pathophysiological mechanisms associated with AF.

vWF/ADAMTS13 is associated with on-aspirin residual platelet reactivity and clinical outcome in patients with stable coronary artery disease.

BACKGROUND: The mechanisms behind residual platelet reactivity (RPR) despite aspirin treatment are not established. It has been shown that coronary artery disease (CAD) patients with high on-aspirin RPR have elevated levels of von Willebrand factor (vWF). ADAMTS13 is a metalloprotease cleaving ultra large vWF multimers into less active fragments.Our aim was to investigate whether ADAMTS13 and vWF/ADAMTS13 ratio were associated with high RPR, and further with clinical endpoints after 2 years. METHODS: Stable aspirin-treated CAD patients (n = 999) from the ASCET trial. RPR was assessed by PFA-100. ADAMTS13 antigen and activity were analysed using chromogenic assays. Endpoints were a composite of acute myocardial infarction, stroke and death. RESULTS: The number of patients with high RPR was 258 (25.8%). Their serum thromboxane B2 (TxB2) levels were low, indicating inhibition of COX-1. They had significantly lower levels of ADAMTS13 antigen compared to patients with low RPR (517 vs 544 ng/mL, p = 0.001) and significantly lower ADAMTS13 activity (0.99 vs 1.04 IU/mL, p = 0.020). The differences were more pronounced when relating RPR to ratios of vWF/ADAMTS13 antigen and vWF/ADAMTS13 activity (p < 0.001, both). We found an inverse correlation between vWF and ADAMTS13 antigen (r = -0.14, p < 0.001) and ADAMTS13 activity (r = -0.11, p < 0.001). No correlations between TxB2 and ADAMTS13 antigen or activity, were observed, implying that ADAMTS13 is not involved in TxB2 production. Patients who experienced endpoints (n = 73) had higher vWF level (113 vs 105%, p = 0.032) and vWF/ADAMTS13 antigen ratio (0.23 vs 0.20, p = 0.012) compared to patients without. When dichotomizing vWF/ADAMTS13 antigen at median level we observed that patients above median had higher risk for suffering endpoints, with an adjusted OR of 1.86 (95% CI 1.45, 2.82). CONCLUSION: These results indicate that ADAMTS13 is of importance for RPR, and that it in combination with vWF also is associated with clinical endpoints in stable CAD patients on aspirin. TRIAL REGISTRATION: Clinicaltrials.gov NCT00222261. Registered 13.09.2005. Retrospectively registered.

Effect of sinus rhythm restoration on markers of thrombin generation in atrial fibrillation.

BACKGROUND: Atrial fibrillation (AF) confers a hypercoagulable state; however, it is not clear whether restoration of sinus rhythm is associated with normalisation of markers of thrombogenesis. We studied the impact of sustained sinus rhythm on prothrombotic markers, and their predictive abilities in foreseeing rhythm outcome after cardioversion. METHODS: In a double blind, placebo-controlled study, 171 patients referred for electrical cardioversion of persistent AF were randomised to receive candesartan or placebo for 3-6 weeks before and 6 months after cardioversion. Endogenous thrombin potential (ETP), prothrombin fragment 1 + 2 (F1 + 2) and D-dimer were measured before cardioversion and at end of study. These markers were also measured in a reference group comprising 49 subjects without AF. RESULTS: The markers remained unchanged in those 28 patients who maintained sinus rhythm. Discontinuation of warfarin treatment in a subset of 13 low-risk patients in sinus rhythm was associated with significantly higher levels of D-dimer and F1 + 2 compared to the reference group; D-dimer (456 ng/mL (276, 763) vs. 279 ng/mL (192, 348), p = 0.002) and F1 + 2 (700 pmol/L (345, 845) vs. 232 pmol/L (190, 281), p < 0.001). None of the markers were associated with rhythm outcome after electrical cardioversion. CONCLUSIONS: Sustained sinus rhythm for 6 months after cardioversion for AF had no impact on ETP, F1 + 2 or D-dimer levels. Discontinuation of warfarin in low-risk patients with sustained sinus rhythm was associated with significantly higher levels of D-dimer and F1 + 2 compared to the reference group. Our results suggest persistent hypercoagulability in AF patients despite long-term maintenance of sinus rhythm. TRIAL REGISTRATION: The CAPRAF study was registered at clinicaltrials.gov (NCT00130975) in August 2005.

Pro-coagulant activity during exercise testing in patients with coronary artery disease.

BACKGROUND: Strenuous exercise may trigger myocardial infarction through increased pro-coagulant activity. We aimed to investigate whether patients referred for exercise testing, who were found to have angiographically verified coronary artery disease (CAD), have a more hypercoagulable profile during exercise testing than those without CAD. METHODS: Patients with symptoms of stable CAD were examined with exercise electrocardiography on bicycle ergometer. Venous blood samples were taken at rest and within 5 min after end of exercise. The following haemostatic variables were analyzed: tissue factor pathway inhibitor (TFPI) activity and antigen, prothrombin fragment 1 + 2 (F1 + 2), D-dimer and endogenous thrombin potential (ETP). All participants underwent conventional coronary angiography. CAD was defined as having any degree of atherosclerosis. RESULTS: Out of the 106 patients enrolled, 70 were found to have CAD. Mean exercise duration was 10:06 ± 4:11 min, with no significant differences between the groups. A significant increase from baseline to after exercise testing was observed in all measured markers in the total population (p ≤ 0.002 for all). In patients with angiographically verified CAD, total TFPI was significantly lower at baseline compared to patients without CAD (median value 67.4 and 76.6 ng/ml respectively, p = 0.027). However, no significant differences in changes of any of the measured markers during exercise were observed between the two groups. CONCLUSION: Pro-coagulant activity increased during short-term strenuous exercise testing in patients with symptoms suggestive of CAD. However the hypercoagulable state observed, was not more pronounced in patients with angiographically verified CAD compared to patients without CAD. NCT01495091.

A Double-Blinded Randomized Study Investigating a Possible Anti-Inflammatory Effect of Saxagliptin versus Placebo as Add-On Therapy in Patients with Both Type 2 Diabetes And Stable Coronary Artery Disease.

BACKGROUND: Promising results regarding potential anti-inflammatory and antiatherosclerotic effects of gliptins have been reported. Our aim was to investigate whether saxagliptin treatment modifies expression of inflammatory markers, primarily in peripheral blood mononuclear cells (PBMCs) and in circulating leukocytes in patients with stable coronary artery disease (CAD) and T2DM. METHODS: Patients (n = 12) were randomized to saxagliptin 5 mg daily or placebo for 3 months. Samples were taken at baseline and end of study in fasting state prior to intake of medications. PBMCs were isolated and cryopreserved at -150°C until ex vivo exposed to 1 ng/mL of lipopolysaccharide (LPS) for 4 hours. Gene expression was performed with custom-designed TaqMan® Arrays and relative quantification by real-time PCR (RT-qPCR). RESULTS: HbA1c was reduced in the saxagliptin-treated group compared to that in the change with placebo (p = 0.042). In unstimulated PBMCs and in circulating leukocytes, we observed a significant increase in IL-10 expression in the saxagliptin group (p = 0.043, both), significantly different from that in the placebo (p = 0.009 and p = 0.032, resp.). No between group differences in changes were observed in any of the selected proinflammatory markers. CONCLUSION: In our small cohort of patients with combined T2DM and CAD, a possible anti-inflammatory effect of saxagliptin, observed in the present study by upregulation of IL-10 in leukocytes, needs to be confirmed in larger studies.