Helicobacter pylori and Pro-Inflammatory Protein Biomarkers in Myocardial Infarction with and without Obstructive Coronary Artery Disease.

Myocardial infarction (MI) with obstructive coronary artery disease (MI-CAD) and MI in the absence of obstructive coronary artery disease (MINOCA) affect different populations and may have separate pathophysiological mechanisms, with greater inflammatory activity in MINOCA compared to MI-CAD. Helicobacter pylori (Hp) can cause systemic inflammation and has been associated with cardiovascular disease (CVD). We aimed to investigate whether Hp infection is associated with concentrations of protein biomarkers of inflammation and CVD. In a case-control study, patients with MINOCA (n = 99) in Sweden were included, complemented by matched subjects with MI-CAD (n = 99) and controls (n = 100). Protein biomarkers were measured with a proximity extension assay in plasma samples collected 3 months after MI. The seroprevalence of Hp and cytotoxin-associated gene A (CagA) was determined using ELISA. The associations between protein levels and Hp status were studied with linear regression. The prevalence of Hp was 20.2%, 19.2%, and 16.0% for MINOCA, MI-CAD, and controls, respectively (p = 0.73). Seven proteins were associated with Hp in an adjusted model: tissue plasminogen activator (tPA), interleukin-6 (IL-6), myeloperoxidase (MPO), TNF-related activation-induced cytokine (TRANCE), pappalysin-1 (PAPPA), soluble urokinase plasminogen activator receptor (suPAR), and P-selectin glycoprotein ligand 1 (PSGL-1). Hp infection was present in one in five patients with MI, irrespective of the presence of obstructive CAD. Inflammatory proteins were elevated in Hp-positive subjects, thus not ruling out that Hp may promote an inflammatory response and potentially contribute to the development of CVD.

Prognostic importance of biomarkers associated with haemostatic, vascular and endothelial disturbances in acute coronary syndrome patients in relation to kidney function.

BACKGROUND: Patients with kidney failure have a high risk for cardiovascular events. We aimed to evaluate the prognostic importance of selected biomarkers related to haemostasis, endothelial function, and vascular regulation in patients with acute coronary syndrome (ACS), and to study whether this association differed in patients with renal dysfunction. METHODS: Plasma was collected in 1370 ACS patients included between 2008 and 2015. Biomarkers were analysed using a Proximity Extension Assay and a Multiple Reaction Monitoring mass spectrometry assay. To reduce multiplicity, biomarkers correlating with eGFR were selected a priori among 36 plasma biomarkers reflecting endothelial and vascular function, and haemostasis. Adjusted Cox regression were used to study their association with the composite outcome of myocardial infarction, ischemic stroke, heart failure or death. Interaction with eGFR strata above or below 60 ml/min/1.73 m2 was tested. RESULTS: Tissue factor, proteinase-activated receptor, soluble urokinase plasminogen activator surface receptor (suPAR), thrombomodulin, adrenomedullin, renin, and angiotensinogen correlated inversely with eGFR and were selected for the Cox regression. Mean follow-up was 5.2 years during which 428 events occurred. Adrenomedullin, suPAR, and renin were independently associated with the composite outcome. Adrenomedullin showed interaction with eGFR strata (p = 0.010) and was associated with increased risk (HR 1.88; CI 1.44-2.45) only in patients with eGFR ≥60 ml/min/ 1.73 m2. CONCLUSIONS: Adrenomedullin, suPAR, and renin were associated with the composite outcome in all. Adrenomedullin, involved in endothelial protection, showed a significant interaction with renal function and outcome, and was associated with the composite outcome only in patients with preserved kidney function.

Biomarker Concentrations and Their Temporal Changes in Patients With Myocardial Infarction and Nonobstructive Compared With Obstructive Coronary Arteries: Results From the PLATO Trial.

Background The pathobiology of myocardial infarction (MI) with nonobstructive coronary arteries (MINOCA) is often uncertain. Investigating biomarker concentrations and their changes may offer novel pathophysiological insights. Methods and Results In this post hoc study of the PLATO (Platelet Inhibition and Patient Outcomes) trial, concentrations of hs-cTnT (high-sensitivity cardiac troponin T), NT-proBNP (N-terminal pro-B-type natriuretic peptide), hs-CRP (high-sensitivity C-reactive protein), and GDF-15 (growth differentiation factor 15) were measured in patients with MINOCA at baseline (n=554) and at 1-month follow-up (n=107). For comparisons, biomarkers were also measured in patients with MI with obstructive (stenosis ≥50%) coronary artery disease (baseline: n=11 106; follow-up: n=2755]). Adjusted linear regression models were used to compare concentrations and their short- and long-term changes. The adjusted geometric mean ratios (GMRs) in patients with MINOCA (median age, 61 years; 50.4% women) indicated lower hs-cTnT (GMR, 0.77 [95% CI, 0.68-0.88]) but higher hs-CRP (GMR, 1.21 [95% CI, 1.08-1.37]) and GDF-15 concentrations (GMR, 1.06 [95% CI, 1.02-1.11]) at baseline compared with patients with MI with obstructive coronary artery disease, whereas NT-proBNP concentrations were similar. Temporal decreases in hs-cTnT, NT-proBNP, and hs-CRP concentrations until 1-month follow-up were more pronounced in patients with MINOCA. At follow-up, patients with MINOCA had lower concentrations of hs-cTnT (GMR, 0.71 [95% CI, 0.60-0.84]), NT-proBNP (GMR, 0.45 [95% CI, 0.36-0.56]), and hs-CRP (GMR, 0.68 [95% CI, 0.53-0.86]). One-month GDF-15 concentrations were similar between both groups with MI. Conclusions Biomarker concentrations suggest greater initial inflammatory activity, similar degree of myocardial dysfunction, and less pronounced myocardial injury during the acute phase of MINOCA compared with MI with obstructive coronary artery disease but also faster myocardial recovery. Registration URL: http://www.clinicaltrials.gov; Unique identifier: NCT00391872.

Differences in biomarker concentrations and predictions of long-term outcome in patients with ST-elevation and non-ST-elevation myocardial infarction.

BACKGROUND: Differences in biomarkers reflective of pathobiology and prognosis between ST-elevation myocardial infarction (STEMI) and non-ST-elevation myocardial infarction (NSTEMI) are incompletely understood and may offer insights for tailoring of treatment. METHODS: This registry-based study included 538 STEMI and 544 NSTEMI patients admitted 2008-2014. Blood samples were collected day 1-3 after admission and 175 biomarkers were analyzed using Proximity Extension Assay and Multiple Reaction Monitoring mass spectrometry. Adjusted Lasso analysis (penalized logistic regression model) was used to select biomarkers that discriminated STEMI from NSTEMI patients. Biomarkers identified by the Lasso analysis were then evaluated in adjusted Cox regressions for associations with death or major adverse cardiovascular events. RESULTS: Biomarkers strongly discriminated STEMI and NSTEMI when considered simultaneously in adjusted Lasso analysis (c-statistic 0.764). Eleven biomarkers independently discriminated STEMI and NSTEMI; seven showing higher concentrations in STEMI: myoglobin, N-terminal pro-B-type natriuretic peptide, serum amyloid A-1 and A-2 protein, ST2 protein, interleukin-6 and chitinase-3-like protein 1; and four showing higher concentrations in NSTEMI: fibroblast growth factor 23, membrane-bound aminopeptidase P, tumor necrosis factor-related activation-induced cytokine and apolipoprotein C-I. During up to 6.6 years of prognostic follow-up, none of these biomarkers exhibited different associations with adverse outcome between STEMI and NSTEMI. CONCLUSIONS: In the acute setting, biomarkers indicated greater myocardial dysfunction and inflammation in STEMI, whereas they displayed a more diverse pathophysiologic pattern in NSTEMI patients. These biomarkers were similarly prognostic in STEMI and NSTEMI patients. The results do not support treating STEMI and NSTEMI patients differently based on the concentrations of these biomarkers.

Predicting outcome in acute myocardial infarction: an analysis investigating 175 circulating biomarkers.

AIMS: There is a paucity of studies comprehensively comparing the prognostic value of larger arrays of biomarkers indicative of different pathobiological axes in acute myocardial infarction (MI). METHODS AND RESULTS: In this explorative investigation, we simultaneously analysed 175 circulating biomarkers reflecting different inflammatory traits, coagulation activity, endothelial dysfunction, atherogenesis, myocardial dysfunction and damage, apoptosis, kidney function, glucose-, and lipid metabolism. Measurements were performed in samples from 1099 MI patients (SWEDEHEART registry) applying two newer multimarker panels [Proximity Extension Assay (Olink Bioscience), Multiple Reaction Monitoring mass spectrometry]. The prognostic value of biomarkers regarding all-cause mortality, recurrent MI, and heart failure hospitalizations (median follow-up ≤6.6 years) was studied using Lasso analysis, a penalized logistic regression model that considers all biomarkers simultaneously while minimizing the risk for spurious findings. Tumour necrosis factor-related apoptosis-inducing ligand receptor 2 (TRAIL-R2), ovarian cancer-related tumour marker CA 125 (CA-125), and fibroblast growth factor 23 (FGF-23) consistently predicted all-cause mortality in crude and age/sex-adjusted analyses. Growth-differentiation factor 15 (GDF-15) was strongly predictive in the crude model. TRAIL-R2 and B-type natriuretic peptide (BNP) consistently predicted heart failure hospitalizations. No biomarker predicted recurrent MI. The prognostic value of all biomarkers was abrogated following additional adjustment for clinical variables owing to our rigorous statistical approach. CONCLUSION: Apart from biomarkers with established prognostic value (i.e. BNP and to some extent GDF-15), several 'novel' biomarkers (i.e. TRAIL-R2, CA-125, FGF-23) emerged as risk predictors in patients with MI. Our data warrant further investigation regarding the utility of these biomarkers for clinical decision-making in acute MI.

Clinical and prognostic implications of C-reactive protein levels in myocardial infarction with nonobstructive coronary arteries.

BACKGROUND: Myocardial infarction with nonobstructive coronary arteries (MINOCA) is a heterogeneous condition. Recent studies suggest that MINOCA patients may have a proinflammatory disposition. The role of inflammation in MINOCA may thus be distinct to myocardial infarction with significant coronary artery disease (MI-CAD). HYPOTHESIS: We hypothesized that inflammation reflected by C-reactive protein (CRP) levels might carry unique clinical information in MINOCA. METHODS: This retrospective registry-based cohort study (SWEDEHEART) included 9916 patients with MINOCA and 97 970 MI-CAD patients, used for comparisons. Multivariable-adjusted regressions were applied to investigate the associations of CRP levels with clinical variables, all-cause mortality and major cardiovascular events (MACE) during a median follow-up of up to 5.3 years. RESULTS: Median admission CRP levels in patients with MINOCA and MI-CAD were 5.0 (interquartile range 2.0-9.0) mg/dl and 5.0 (interquartile range 2.1-10.0 mg/dl), respectively. CRP levels in MINOCA exhibited independent associations with various cardiovascular risk factors, comorbidities and estimates of myocardial damage. The association of CRP with peripheral artery disease tended to be stronger compared to MI-CAD. The associations with female sex, renal dysfunction and myocardial damage were stronger in MI-CAD. CRP independently predicted all-cause mortality in MINOCA (hazard ratio 1.22 [95% confidence interval 1.17-1.26]), similar to MI-CAD (p interaction = 0.904). CRP also predicted MACE (hazard ratio 1.08 [95% confidence interval 1.04-1.12]) but this association was weaker compared to MI-CAD (p interaction<.001). CONCLUSIONS: We found no evidence indicating the presence of a specific inflammatory pattern in acute MINOCA compared to MI-CAD. However, CRP levels were independently, albeit moderately associated with adverse outcome.

Sex-differences in circulating biomarkers during acute myocardial infarction: An analysis from the SWEDEHEART registry.

BACKGROUND: Sex-differences in the pathobiology of myocardial infarction are well established but incompletely understood. Improved knowledge on this topic may help clinicians to improve management of men and women with myocardial infarction. METHODS: In this registry-based cohort study (SWEDEHEART), we analyzed 175 circulating biomarkers reflecting various pathobiological axes in 856 men and 243 women admitted to Swedish coronary care units because of myocardial infarction. Two multimarker panels were applied (Proximity Extension Assay [Olink Bioscience], Multiple Reaction Monitoring mass spectrometry). Lasso analysis (penalized logistic regression), multiple testing-corrected Mann-Whitney tests and Cox regressions were used to assess sex-differences in the concentrations of these biomarkers and their implications on all-cause mortality and major adverse events (median follow-up up to 6.6 years). RESULTS: Biomarkers provided a very high discrimination between both sexes, when considered simultaneously (c-statistics 0.972). Compared to women, men had higher concentrations of six biomarkers with the most pronounced differences seen for those reflecting atherogenesis, myocardial necrosis and metabolism. Women had higher concentrations of 14 biomarkers with the most pronounced differences seen for those reflecting activation of the renin-angiotensin-aldosterone axis, inflammation and for adipokines. There were no major variations between sexes in the associations of these biomarkers with outcome. CONCLUSIONS: Severable sex-differences exist in the expression of biomarkers in patients with myocardial infarction. While these differences had no impact on outcome, our data suggest the presence of various sex-related pathways involved in the development of coronary atherosclerosis, the progression to plaque rupture and acute myocardial damage, with a greater heterogeneity in women.

Diagnosing type 2 myocardial infarction in clinical routine. A validation study.

Objective. Since 2010, myocardial infarction (MI) patients reported to the Swedish registry for MI (SWEDEHEART) are routinely classified into MI subtypes. The registry has been used to study the type 2 MI population but the MI-classification in the registry has not previously been validated. The aim of this study was to validate the type 2 MI classification in the registry. Design. A total of 772 patients diagnosed with MI in 2011 and reported to the SWEDEHEART registry were included in the study. All patients were retrospectively classified into MI type 1-5 or myocardial injury by independent reviewers strictly adhering to The Third Universal Definition of MI. This gold standard classification was compared with the classification in the registry. Results. Forty-eight (6.2%) patients were classified as type 2 MI in the registry compared with 93 (12.0%) according to the gold standard classification. A type 2 MI diagnosis was confirmed in 30 out of the 48 type 2 MI patients in the registry (PPV: 62.5%). There was a moderate rate of agreement (κ: 0.43) between the gold standard classification and the classification in SWEDEHEART in deciding a type 2 MI diagnosis. Conclusion. The SWEDEHEART registry agreed moderately with the gold standard in classifying patients with type 2 MI diagnosis. Thus, studies on patients with type 2 MI in the registry should be interpreted with caution. Since the prevalence of type 2 MI is substantially underestimated in SWEDEHEART, the registry should not be used to study the prevalence of type 2 MI.

Increased Inflammatory Activity in Patients 3 Months after Myocardial Infarction with Nonobstructive Coronary Arteries.

BACKGROUND: Around 5%-10% of patients with myocardial infarction (MI) present with nonobstructive coronary arteries (MINOCA). We aimed to assess pathophysiological mechanisms in MINOCA by extensively evaluating cardiovascular biomarkers in the stable phase after an event, comparing MINOCA patients with cardiovascular healthy controls and MI patients with obstructive coronary artery disease (MI-CAD). METHODS: Ninety-one biomarkers were measured with a proximity extension assay 3 months after MI in 97 MINOCA patients, 97 age- and sex-matched MI-CAD patients, and 98 controls. Lasso analyses (penalized logistic regression models) and adjusted multiple linear regression models were used for statistical analyses. RESULTS: In the Lasso analysis (MINOCA vs MI-CAD), 8 biomarkers provided discriminatory value: P-selectin glycoprotein ligand 1, C-X-C motif chemokine 1, TNF-related activation-induced cytokine, and pappalysin-1 (PAPPA) with increasing probabilities of MINOCA, and tissue-type plasminogen activator, B-type natriuretic peptide, myeloperoxidase, and interleukin-1 receptor antagonist protein with increasing probabilities of MI-CAD. Comparing MINOCA vs controls, 7 biomarkers provided discriminatory value: N-terminal pro-B-type natriuretic peptide, renin, NF-κ-B essential modulator, PAPPA, interleukin-6, and soluble urokinase plasminogen activator surface receptor with increasing probabilities of MINOCA, and agouti-related protein with increasing probabilities of controls. Adjusted multiple linear regression analyses showed that group affiliation was associated with the concentrations of 7 of the 8 biomarkers in the comparison MINOCA vs MI-CAD and 5 of the 7 biomarkers in MINOCA vs controls. CONCLUSIONS: Three months after the MI, the biomarker concentrations indicated greater inflammatory activity in MINOCA patients than in both MI-CAD patients and healthy controls, and a varying degree of myocardial dysfunction among the 3 cohorts.

Prognosis in relation to high-sensitivity cardiac troponin T levels in patients with myocardial infarction and non-obstructive coronary arteries.

BACKGROUND: Myocardial infarction (MI) with non-obstructive coronary arteries (MINOCA) is a recently recognized condition where biomarkers and prognosis are less well studied than in MI with obstructive coronary artery disease (MI-CAD). We therefore aimed to investigate the one-year prognostic value of high-sensitivity cardiac troponin T (hs-cTnT) levels in MINOCA in comparison to MI-CAD. METHODS: In this registry-based cohort study, we used data from patients with a discharge diagnosis of MI, admitted between 2009 and 2013 to Swedish hospitals using the hs-cTnT assay. Only patients without previously known coronary artery disease were considered. Patients with and without coronary stenosis >50% were regarded to have MI-CAD and MINOCA, respectively. Assessed outcomes included all-cause mortality, cardiovascular (CV) mortality and major CV events (MACE), defined as the composite of CV death or admissions for non-fatal MI, heart failure (HF) or ischemic stroke. RESULTS: The study cohort consisted of 1639 MINOCA and 17,304 MI-CAD patients. In adjusted analyses, hs-cTnT (ln) in MINOCA patients predicted all-cause mortality (HR 1.32 [95% CI 1.11-1.56]), CV mortality (HR 2.11 [95% CI 1.51-2.96]) and MACE (HR 1.44 [95% CI 1.20-1.72]). Hs-cTnT (ln) also predicted readmissions for HF (HR 1.51 [95% CI 1.51-2.96]) but not non-fatal MI or stroke. Interaction analyses suggested that hs-cTnT (ln) was at least as prognostic in patients with MINOCA compared to MI-CAD. CONCLUSIONS: Hs-cTnT levels in MINOCA patients are strong and independent predictors of adverse outcome. Consideration of hs-cTnT levels is important for risk assessment of MINOCA patients.

Interphysician agreement on subclassification of myocardial infarction.

OBJECTIVE: The universal definition of myocardial infarction (MI) differentiates MI due to oxygen supply/demand mismatch (type 2) from MI due to plaque rupture (type 1) as well as from myocardial injuries of non-ischaemic or multifactorial nature. The purpose of this study was to investigate how often physicians agree in this classification and what factors lead to agreement or disagreement. METHODS: A total of 1328 patients diagnosed with MI at eight different Swedish hospitals 2011 were included. All patients were retrospectively reclassified into different MI or myocardial injury subtypes by two independent specially trained physicians, strictly adhering to the third universal definition of MI. RESULTS: Overall, there was a moderate interobserver agreement with a kappa coefficient (κ) of 0.55 in this classification. There was substantial agreement when distinguishing type 1 MI (κ: 0.61), compared with moderate agreement when distinguishing type 2 MI (κ: 0.54). In multivariate logistic regression analyses, ST elevation MI (P<0.001), performed coronary angiography (P<0.001) and larger changes in troponin levels (P=0.023) independently made the physicians agree significantly more often, while they disagreed more often with symptoms of dyspnoea (P<0.001), higher systolic blood pressure (P=0.001) and higher C reactive protein levels on admission (P=0.016). CONCLUSION: Distinguishing MI types is challenging also for trained adjudicators. Although strictly adhering to the third universal definition of MI, differentiation between type 1 MI, type 2 MI and myocardial injury only gave a moderate rate of interobserver agreement. More precise and clinically applicable criteria for the current classification, particularly for type 2 MI diagnosis, are urgently needed.

Interleukin-35 administration counteracts established murine type 1 diabetes--possible involvement of regulatory T cells.

The anti-inflammatory cytokine IL-35 is produced by regulatory T (Treg) cells to suppress autoimmune and inflammatory responses. The role of IL-35 in type 1 diabetes (T1D) remains to be answered. To elucidate this, we investigated the kinetics of Treg cell response in the multiple low dose streptozotocin induced (MLDSTZ) T1D model and measured the levels of IL-35 in human T1D patients. We found that Treg cells were increased in MLDSTZ mice. However, the Treg cells showed a decreased production of anti-inflammatory (IL-10, IL-35, TGF-ß) and increased pro-inflammatory (IFN-γ, IL-2, IL-17) cytokines, indicating a phenotypic shift of Treg cells under T1D condition. IL-35 administration effectively both prevented development of, and counteracted established MLDSTZ T1D, seemingly by induction of Eos expression and IL-35 production in Treg cells, thus reversing the phenotypic shift of the Treg cells. IL-35 administration reversed established hyperglycemia in NOD mouse model of T1D. Moreover, circulating IL-35 levels were decreased in human T1D patients compared to healthy controls. These findings suggest that insufficient IL-35 levels play a pivotal role in the development of T1D and that treatment with IL-35 should be investigated in treatment of T1D and other autoimmune diseases.

Concomitant analysis of Helios and Neuropilin-1 as a marker to detect thymic derived regulatory T cells in naïve mice.

Regulatory T (Treg) cells are characterized by the expression of CD4, CD25 and the intracellular Foxp3. However, these markers do not indicate whether Treg cells are thymic derived Treg (tTreg) cells or peripherally induced Treg (pTreg) cells. Recently, Helios and Neuropilin-1 (Nrp1) has been reported as potential markers for tTreg cells. Herein, we used flow cytometry to examine the proportion of CD4(+)CD8(-)CD25(+) Treg cells expressing Helios, Nrp1 and Foxp3 in thymus, pancreatic draining lymph nodes (PDLNs) and spleen of CD-1 mice, and thymus of NOD and C57BL/6 mice. The frequency of Helios(+) cells was higher than that of Nrp1(+) cells in CD4(+)CD8(-)CD25(+) and CD4(+)CD8(-)CD25(+)Foxp3(+) Treg cells in thymus. Interestingly, the proportion of IL-10(+), Ebi3(+)and CTLA-4(+) cells was higher in Helios(+) than Nrp1(+) tTreg cells. The anti-apoptotic activity of Helios(+) tTreg cells was higher in thymus compared to Nrp1(+) tTreg cells. Nrp1 seems to be expressed at a later developmental stage compared to Helios and Foxp3. Furthermore, the expression of Nrp1 in CD4(+)CD25(+) T cells of younger mice did not increase after stimulating them in vitro with anti-CD3 and -CD28. Thus, under these conditions, Helios could be considered a more reliable marker for distinguishing tTreg cells from pTreg cells than Nrp1.