Arginase 1 is upregulated at admission in patients with ST-elevation myocardial infarction

BACKGROUND

The mechanisms underlying rupture of a coronary atherosclerotic plaque and development of myocardial ischemia-reperfusion injury in ST-elevation myocardial infarction (STEMI) remain unresolved. Increased arginase 1 activity leads to reduced nitric oxide (NO) production and increased formation of reactive oxygen species due to uncoupling of the NO-producing enzyme endothelial NO synthase (eNOS). This contributes to endothelial dysfunction, plaque instability and increased susceptibility to ischemia-reperfusion injury in acute myocardial infarction.

OBJECTIVE

The purpose of this study was to test the hypothesis that arginase gene and protein expression are upregulated in patients with STEMI.

METHODS

Two cohorts of patients with STEMI were included. In the first cohort (n = 51), expression of arginase and NO-synthases as well as arginase 1 protein levels were determined and compared to a healthy control group (n = 45). In a second cohort (n = 68), plasma arginase 1 levels and infarct size were determined using cardiac magnetic resonance imaging.

RESULTS

Expression of the gene encoding arginase 1 was significantly elevated at admission and 24-48 h after STEMI but not 3 months post STEMI, in comparison with the control group. Expression of the genes encoding arginase 2 and endothelial NO synthase (NOS3) were unaltered. Arginase 1 protein levels were elevated at admission, 24 h post STEMI and remained elevated for up to 6 months. No significant correlation between plasma arginase 1 protein levels and infarct size was observed.

CONCLUSION

The markedly increased gene and protein expression of arginase 1 already at admission indicates a role of arginase 1 in the development of STEMI.

Plasma catecholamine levels in the acute and subacute stages of takotsubo syndrome: Results from the Stockholm myocardial infarction with normal coronaries 2 study

AIMS

It is well-accepted that takotsubo syndrome (TS) is characterized by a massive surge of plasma catecholamines despite lack of solid evidence. The objective of this study was to examine the hypothesis of a massive catecholamine elevation in TS by studying plasma-free catecholamine metabolites in patients participating in the Stockholm myocardial infarction (MI) with normal coronaries 2 (SMINC-2) study where TS constituted more than one third of the patients.

METHODS AND RESULTS

The patients included in the SMINC-2 study were classified, according to cardiac magnetic resonance (CMR) imaging findings (148 patients), which was performed at a median of 3 days after hospital admission. Plasma-free catecholamine metabolites; metanephrine, normetanephrine, and methoxy-tyramine were measured on day 2-4 after admission. Catecholamine metabolite levels were available in 125 patients. One hundred and ten (88%) of the 125 patients included in SMINC-2 study, and 38 (86.4%) of the 44 patients with TS had completely normal plasma metanephrine and normetanephrine levels. All patients had normal plasma methoxy-tyramine levels. Fourteen (11.2%) of the 125 patients included in SMINC-2 study, and 5 (11.6%) of the 43 patients with TS had mild elevations (approximately 1.2 times the upper normal limits) of either plasma metanephrine or normetanephrine. One patient with pheochromocytoma-triggered TS had marked elevation of plasma metanephrine and mild elevation of plasma normetanephrine. There were no significant differences between the number or degree of catecholamine metabolite elevations between the different groups of patients with CMR imaging diagnosis included in SMINC-2 study.

CONCLUSION

There was no evidence of massive catecholamine elevations in the acute and subacute stages of TS apart from one patient with pheochromocytoma-induced TS. Most of the TS patients had normal catecholamine metabolites indicating that blood-borne catecholamines do not play a direct role in the pathogenesis of TS.

Short- and Long-Term Clinical Outcomes for Patients With Takotsubo Syndrome and Patients With Myocardial Infarction: A Report From the Swedish Coronary Angiography and Angioplasty Registry

Background

Takotsubo syndrome (TS) is a potentially life‐threatening acute cardiac syndrome with a clinical presentation similar to myocardial infarction and for which the natural history, management, and outcome remain incompletely understood. Our aim was to assess the relative short‐term mortality risk of TS, ST‐segment–elevation myocardial infarction (STEMI), and non‐STEMI (NSTEMI) and to identify predictors of in‐hospital complications and poor prognosis in patients with TS.

Methods and Results

This is an observational cohort study based on the data from the SCAAR (Swedish Coronary Angiography and Angioplasty Registry). We included all patients (n=117 720) who underwent coronary angiography in Sweden attributed to TS (N=2898 [2.5%]), STEMI (N=48 493 [41.2%]), or NSTEMI (N=66 329 [56.3%]) between January 2009 and February 2018. We compared patients with TS to those with NSTEMI or STEMI. The primary end point was all‐cause mortality at 30 days. Secondary outcomes were acute heart failure (Killip Class ≥2) and cardiogenic shock (Killip Class 4) at the time of angiography. Patients with TS were more often women compared with patients with STEMI or NSTEMI. TS was associated with unadjusted and adjusted 30‐day mortality risks lower than STEMI (adjusted hazard ratio [adjHR], 0.60; 95% CI, 0.48–0.76; P<0.001), but higher than NSTEMI (adjHR, 2.70; 95% CI, 2.14–3.41; P<0.001). Compared with STEMI, TS was associated with a similar risk of acute heart failure (adjHR, 1.26; 95% CI, 0.91–1.76; P=0.16) but a lower risk of cardiogenic shock (adjHR, 0.55; 95% CI, 0.34–0.89; P=0.02). The relative 30‐day mortality risk for TS versus STEMI and NSTEMI was higher for smokers than nonsmokers (adjusted P interaction STEMI=0.01 and P interaction NSTEMI=0.01).

Conclusions

The 30‐day mortality rate in TS was higher than in NSTEMI but lower than STEMI despite a similar risk of acute heart failure in TS and STEMI. Among patients with TS, smoking was an independent predictor of mortality.

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.

Early Comprehensive Cardiovascular Magnetic Resonance Imaging in Patients With Myocardial Infarction With Nonobstructive Coronary Arteries

OBJECTIVES

The objective of the SMINC-2 (Stockholm Myocardial Infarction With Normal Coronaries 2) study was to determine if more than 70% of patients with myocardial infarction with nonobstructed coronary arteries (MINOCA), investigated early with comprehensive cardiovascular magnetic resonance (CMR), could receive a diagnosis entirely by imaging.

BACKGROUND

The etiology of MINOCA is heterogeneous, including coronary, cardiac, and noncardiac causes. Patients with MINOCA, therefore, represent a diagnostic challenge where CMR is increasingly used.

METHODS

The SMINC-2 study was a prospective study of 148 patients with MINOCA imaged with 1.5-T CMR with T₁ and extracellular volume mapping early after hospital admission, compared to 150 patients with MINOCA imaged using 1.5-T CMR without mapping techniques from the SMINC-1 study as historic controls.

RESULTS

CMR was performed at a median of 3 (SMINC-2) versus 12 (SMINC-1) days after hospital admission. In total, 77% of patients received a diagnosis with CMR imaging in the SMINC-2 study compared to 47% in the SMINC-1 study (p < 0.001). Compared to SMINC-1, CMR in SMINC-2 detected higher proportions of myocarditis (17% vs. 7%; p = 0.01) and takotsubo syndrome (35% vs. 19%; p = 0.002) but similar proportions of myocardial infarction (22% vs. 19%; p = 0.56) and other cardiomyopathies (3% vs. 2%; p = 0.46).

CONCLUSIONS

The results of the SMINC-2 study show that 77% of all patients with MINOCA received a diagnosis when imaged early with CMR, including advanced tissue characterization, which was a considerable improvement in comparison to the SMINC-1 study. This supports the use of early CMR imaging as a diagnostic tool in the investigation of patients with MINOCA. (Stockholm Myocardial Infarction With Normal Coronaries [SMINC]-2 Study on Diagnosis Made by Cardiac MRI [SCMINC-2]; NCT02318498).

Diurnal QT analysis in patients with sotalol after cardioversion of atrial fibrillation

Background

The risk of ventricular arrhythmias in patients on QT prolonging drugs is indicated to be increased early after cardioversion (CV) of atrial fibrillation (AF) to sinus rhythm (SR). Sotalol, used to prevent AF relapse, prolongs cardiac repolarization and corrected QT interval (QTc). A pronounced QTc prolongation is an established marker of pro‐arrhythmias. Our objective was to use novel technique to quantify and evaluate the diurnal variation of the QTc interval after elective CV to SR in patients on sotalol or metoprolol.

Methods

Fifty patients underwent twelve‐lead Holter recording for 24 hr after elective CV for persistent AF. All patients had the highest tolerable stable dose of sotalol (n = 27) or metoprolol (n = 23). Measurements of QT and RR intervals were performed on all valid beats.

Results

A clear diurnal variation of both HR and QTc was seen in both groups, more pronounced in patients on sotalol, where a high percentage of heartbeats with QTc >500 ms was observed, especially at night. Six patients (22%) on sotalol but none on metoprolol had >20% of all heart beats within the 24‐hour recording with QTc >500 ms.

Conclusion

Twenty‐four‐hour Holter recordings with QT‐measurement immediately after CV demonstrated that one in five patients on sotalol had >20% of all heart beats with prolonged QTc >500 ms, especially during night‐time. The QTc diurnal variation was retained in patients on β‐blockade or a potent class III anti‐arrhythmic drug with β‐blocking properties.

Stimulating the Resolution of Inflammation Through Omega-3 Polyunsaturated Fatty Acids in COVID-19: Rationale for the COVID-Omega-F Trial

Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19). SARS-CoV-2 triggers an immune response with local inflammation in the lung, which may extend to a systemic hyperinflammatory reaction. Excessive inflammation has been reported in severe cases with respiratory failure and cardiovascular complications. In addition to the release of cytokines, referred to as cytokine release syndrome or "cytokine storm," increased pro-inflammatory lipid mediators derived from the omega-6 polyunsaturated fatty acid (PUFA) arachidonic acid may cause an "eicosanoid storm," which contributes to the uncontrolled systemic inflammation. Specialized pro-resolving mediators, which are derived from omega-3 PUFA, limit inflammatory reactions by an active process called resolution of inflammation. Here, the rationale for omega-3 PUFA supplementation in COVID-19 patients is presented along with a brief overview of the study protocol for the trial "Resolving Inflammatory Storm in COVID-19 Patients by Omega-3 Polyunsaturated Fatty Acids - A single-blind, randomized, placebo-controlled feasibility study" (COVID-Omega-F). EudraCT: 2020-002293-28; clinicaltrials.gov: NCT04647604.

Myocardial Infarction in Systemic Lupus Erythematosus: Incidence and Coronary Angiography Findings

An association between acute myocardial infarction (AMI) and systemic lupus erythematosus (SLE) has been suggested. The cause of AMI is presumed to be atherothrombosis. In the present study, the primary objective was to assess incident AMI cases and the secondary objective was to estimate the proportion of myocardial infarction with nonobstructive coronary arteries (MINOCA) in patients with SLE. All Swedish patients with SLE without AMI before 1996 (n = 4192) were followed for 20 years in the national patient registry. For each SLE patient, 10 age- and sex-matched controls without SLE and AMI before 1996 (n = 41 892) were identified. Data from patients and controls with AMI after 1996 were linked with the Swedish coronary angiography and angioplasty register; 549 (13%) and 3352 (8%) first AMIs occurred in patients with SLE and controls, respectively. The incidence of AMI was 9.6 (95% CI: 8.9-10.5) and 4.9 (95% CI: 4.8-5.1) events/1000 person-years in patients with SLE and controls, respectively. The proportion of MINOCA was 10.8% in patients with SLE and 13.8% in controls (P = .261), respectively. In conclusion, the incidence of AMI is increased in a European population of patients with SLE but there is no indication that the proportion of MINOCA is increased in these patients.

Randomized evaluation of beta blocker and ACE-inhibitor/angiotensin receptor blocker treatment in patients with myocardial infarction with non-obstructive coronary arteries (MINOCA-BAT): Rationale and design

Myocardial infarction with non-obstructive coronary arteries (MINOCA) is common and occurs in 6-8% of all patients fulfilling the diagnostic criteria for acute myocardial infarction (AMI). This paper describes the rationale behind the trial 'Randomized Evaluation of Beta Blocker and ACE-Inhibitor/Angiotensin Receptor Blocker Treatment (ACEI/ARB) of MINOCA patients' (MINOCA-BAT) and the need to improve the secondary preventive treatment of MINOCA patients. METHODS: MINOCA-BAT is a registry-based, randomized, parallel, open-label, multicenter trial with 2:2 factorial design. The primary aim is to determine whether oral beta blockade compared with no oral beta blockade, and ACEI/ARB compared with no ACEI/ARB, reduce the composite endpoint of death of any cause, readmission because of AMI, ischemic stroke or heart failure in patients discharged after MINOCA without clinical signs of heart failure and with left ventricular ejection fraction ≥40%. A total of 3500 patients will be randomized into four groups; e.g. ACEI/ARB and beta blocker, beta blocker only, ACEI/ARB only and neither ACEI/ARB nor beta blocker, and followed for a mean of 4 years. SUMMARY: While patients with MINOCA have an increased risk of serious cardiovascular events and death, whether conventional secondary preventive therapies are beneficial has not been assessed in randomized trials. There is a limited basis for guideline recommendations in MINOCA. Furthermore, studies of routine clinical practice suggest that use of secondary prevention therapies in MINOCA varies considerably. Thus results from this trial may influence future treatment strategies and guidelines specific to MINOCA patients.

Use of proteomics to identify biomarkers associated with chronic kidney disease and long-term outcomes in patients with myocardial infarction

BACKGROUND

Patients with chronic kidney disease (CKD) have poor outcomes following myocardial infarction (MI). We performed an untargeted examination of 175 biomarkers to identify those with the strongest association with CKD and to examine the association of those biomarkers with long-term outcomes.

METHODS

A total of 175 different biomarkers from MI patients enrolled in the Swedish Web-System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies (SWEDEHEART) registry were analysed either by a multiple reaction monitoring mass spectrometry assay or by a multiplex assay (proximity extension assay). Random forests statistical models were used to assess the predictor importance of biomarkers, CKD and outcomes.

RESULTS

A total of 1098 MI patients with a median estimated glomerular filtration rate of 85 mL min^-1 /1.73 m² were followed for a median of 3.2 years. The random forests analyses, without and with adjustment for differences in demography, comorbidities and severity of disease, identified six biomarkers (adrenomedullin, TNF receptor-1, adipocyte fatty acid-binding protein-4, TNF-related apoptosis-inducing ligand receptor 2, growth differentiation factor-15 and TNF receptor-2) to be strongly associated with CKD. All six biomarkers were also amongst the 15 strongest predictors for death, and four of them were amongst the strongest predictors of subsequent MI and heart failure hospitalization.

CONCLUSION

In patients with MI, a proteomic approach could identify six biomarkers that best predicted CKD. These biomarkers were also amongst the most important predictors of long-term outcomes. Thus, these biomarkers indicate underlying mechanisms that may contribute to the poor prognosis seen in patients with MI and CKD.

Spontaneous coronary artery dissection – contemporary management and outcome of a national cohort

Background

Spontaneous coronary artery dissection (SCAD) is proposed to cause 1–4% of all acute myocardial infarctions (AMI).

The aim of this study was to conduct a first description of Swedish SCAD patients regarding the prevalence of risk factors, treatment and prognosis.

Method

All patients with AMI registered in the Swedish Coronary Angiography and Angioplasty Register (SCAAR) December 2015 until December 2017 were included. The index angiographies of the SCAD patients were reevaluated by an independent angiographer at each center. Patients with non-SCAD AMI (n=31670) were used for comparison.

Results

SCAD was identified in 137 patients with AMI (100 women, 37 men). The SCAD population was younger than the non-SCAD population 53.9 (51.7–56.1) vs 68.5 (68.3–68.6) years, more often women (73.0 vs 30.7%) and presented with less risk factors: diabetes 2.9 vs 20.8%; hypertension 27.0 vs 57.6%; smoking 41.2 vs 58.1%; statin therapy 12.4 vs 36.9% and previous AMI 7.3 vs 19.6% (p&lt;0.001 for all comparisons).

SCAD patients less frequently underwent percutaneous coronary intervention (PCI) 43.1 vs 70.8% (p&lt;0.001) and received less statin treatment, 78.9 vs 91.5% (p&lt;0.001).

There was no significant difference regarding treatment with aspirin or double antiplatelet therapy at discharge: 93 vs 89.7% (p=0.45) and 86.7 vs 84.2%, respectively (p=0,43).

There was no significant difference in one-year mortality 6.6 vs 8.2% (p=0.57).

Conclusions

With a current prevalence of 0.43% of all Swedish AMIs, data supports SCAD being an underdiagnosed condition with a prognosis resembling that of non-SCAD AMI. Furthermore, SCAD patients are younger and harbor less cardiovascular risk factors. While significant differences in management are present, current therapeutic strategies of the two groups are similar, indicating overtreatment of SCAD.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Swedish Heart-Lung foundation, ALF funding

Designing a Web-Based Psychological Intervention for Patients With Myocardial Infarction With Nonobstructive Coronary Arteries: User-Centered Design Approach

Background

The involvement of patient research partners (PRPs) in research aims to safeguard the needs of patient groups and produce new interventions that are developed based on patient input. Myocardial infarction with nonobstructive coronary arteries (MINOCA), unlike acute myocardial infarction (MI) with obstructive coronary arteries, is presented with no significant obstructive coronary artery disease. Patients with this diagnosis are a subset of those diagnosed with traditional MI and often need more psychological support, something that is presently not established in the current treatment scheme in Swedish health care or elsewhere, to our knowledge. An internet-delivered intervention might offer patients with MINOCA the opportunity to access a psychological treatment that is tailored to their specific needs after MINOCA and could therefore supplement the existing medical care in an easily accessible format.

Objective

This paper aims to describe the development of a therapist-guided, internet-delivered psychological intervention designed specifically for patients with MINOCA.

Methods

The study used a participatory design that involved 7 PRPs diagnosed with MINOCA who collaborated with a team consisting of researchers, cardiologists, and psychologists. Intervention content was developed iteratively and presented to the PRPs across several prototypes, each continually adjusted and redesigned according to the feedback received. The intervention and experience of it were discussed by PRPs in a final meeting and then presented to a panel of 2 clinical psychologists and a cardiologist for further input.

Results

The outcome of the collaboration between PRPs and the research group produced a web-based psychological 9-step program focusing on stress, worry, and valued action. The input from PRPs contributed substantially to the therapy content, homework tasks, interactive activities, multimedia, and design presentation.

Conclusions

Working with PRPs to develop an intervention for people with MINOCA produced a web-based intervention that can be further evaluated with the goal of offering a new psychological treatment option to a patient group currently without one. Direct contribution from PRPs enabled us to obtain relevant, insightful, and valuable feedback that was put towards the overall design and content of the intervention.

Self-rated stress and experience in patients with Takotsubo syndrome: a mixed methods study

BACKGROUND

A relation to stress and stressful triggers is often, but not always, described in patients with Takotsubo syndrome. Few studies have focused on patients' self-rated stress in combination with qualitative experiences of stress in Takotsubo syndrome.

AIMS

The aim of this study was to describe stress before and after the onset of Takotsubo syndrome.

METHODS

Twenty patients were recruited from five major hospitals in Stockholm, Sweden between December 2014 and November 2018. A mixed methods design was used containing the validated questionnaire, perceived stress scale (PSS-14) filled in at baseline and at a 6 and 12-month follow-up, respectively. Qualitative interviews were made at the 6-month follow-up.

RESULTS

Self-rated stress, measured by the perceived stress scale, showed stress levels above the cut-off value of 25, at the onset of Takotsubo syndrome (median 30.5). Stress had decreased significantly at the 12-month follow-up (median 20.5, P = 0.039) but remained high in one third of the patients. Qualitative interviews confirmed a high long-term stress and half of the patients had an acute stress trigger before the onset of Takotsubo syndrome. The qualitative interviews showed that the patients had reflected on and tried to find ways to deal with stress, but for many this was not successful.

CONCLUSION

Patients with Takotsubo syndrome reported long-term stress sometimes with an acute stress trigger before the onset of Takotsubo syndrome. Stress decreased over time but remained high for a considerable number of patients. Despite reflection over stress and attempts to deal with stress many were still affected after 6 months. New treatment options are needed for patients with Takotsubo syndrome.

The MOVEMENT Trial

Background

Morphine administration is a strong predictor of delayed onset of action of orally administered ticagrelor in patients with ST‐segment–elevation myocardial infarction, likely because of impaired gastrointestinal motility. The aim of this study was to evaluate whether the peripheral opioid antagonist methylnaltrexone could improve pharmacodynamics and pharmacokinetics of orally administered ticagrelor in patients with ST‐segment–elevation myocardial infarction receiving morphine.

Methods and Results

The MOVEMENT (Methylnaltrexone to Improve Platelet Inhibition of Ticagrelor in Morphine‐Treated Patients With ST‐Segment Elevation Myocardial Infarction) trial was a multicenter, prospective, randomized, controlled trial in patients with ST‐segment–elevation myocardial infarction treated with morphine and ticagrelor. Upon arrival to the catheterization laboratory, patients were randomized to a blinded intravenous injection of either methylnaltrexone (8 or 12 mg according to weight) or 0.9% sodium chloride. The proportion of patients with high on‐treatment platelet reactivity and plasma concentrations of ticagrelor and AR‐C124910XX were assessed at baseline (arrival in the catheterization laboratory) and 1 and 2 hours later. A total of 82 patients received either methylnaltrexone (n=43) or placebo (n=39). Median (interquartile range) time from ticagrelor administration to randomization was 41 (31–50) versus 45.5 (37–60) minutes (P=0.16). Intravenous methylnaltrexone administration did not significantly affect prevalence of high on‐treatment platelet reactivity at 2 hours after inclusion, the primary end point, when compared with placebo (54% versus 51%, P=0.84). Plasma concentrations of ticagrelor and its active metabolite, the prespecified secondary end points, did not differ significantly between the groups over time. There was no significant difference in patient self‐estimated pain between the groups.

Conclusions

Methylnaltrexone did not significantly improve platelet reactivity or plasma concentrations of orally administered ticagrelor in patients with ST‐segment–elevation myocardial infarction receiving morphine.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02942550.

New candidate genes for ST-elevation myocardial infarction

BACKGROUND

Despite extensive research in atherosclerosis, the mechanisms of coronary atherothrombosis in ST-elevation myocardial infarction (STEMI) patients are undetermined.

OBJECTIVES

Our aim was to find candidate genes involved in STEMI by analysing leucocyte gene expression in STEMI patients, without the influence of secondary inflammation from innate immunity, which was assumed to be a consequence rather than the cause of coronary atherothrombosis.

METHODS

Fifty-one patients were included at coronary angiography because of STEMI. Arterial blood was sampled in the acute phase (P1), at 24-48 h (P2) and at 3 months (P3). Leucocyte RNA was isolated and gene expression analysis was performed by Affymetrix Human Transcriptome Array 2.0. By omission of up- or downregulated genes at P2, secondary changes from innate immunity were excluded. Genes differentially expressed in P1 when compared to the convalescent sample in P3 were determined as genes involved in STEMI.

RESULTS

Three genes were upregulated at P1 compared to P3; ABCG1 (P = 5.81 × 10^-5 ), RAB20 (P = 3.69 × 10^-5 ) and TMEM2 (P = 7.75 × 10^-6 ) whilst four were downregulated; ACVR1 (P = 9.01 × 10^-5 ), NFATC2IP (P = 8.86 × 10^-5 ), SUN1 (P = 3.87 × 10^-5 ) and TTC9C (P = 7.18 × 10^-6 ). These genes were also highly expressed in carotid atherosclerotic plaques.

CONCLUSIONS

We found seven genes involved in STEMI. The study is unique regarding the blood sampling in the acute phase and omission of secondary expressed genes from innate immunity. However, the results need to be replicated by future studies.

Prevalence and cumulative incidence of cancer, and mortality in patients with Takotsubo syndrome with focus on the index event

BACKGROUND

It has been suggested that Takotsubo syndrome (TS) is associated with cancer but previous studies have limitations.

AIM

To make a comprehensive analysis of prevalence and cumulative incidence of cancer, and mortality among TS patients with focus on the index event.

DESIGN

A register-based case-control study.

METHODS

The first new cancer occurrences (International Classification of Diseases C00-C75, C81-C96) were compared between 505 patients with TS without obstructive coronary artery disease (CAD) and four age- and gender-matched controls comprising patients with acute coronary syndrome with obstructive CAD (CAD controls), respectively, with chest-pain without obstructive CAD at coronary angiography (controls without CAD).

RESULTS

The prevalence of cancer before the index event was non-significantly (P = 0.052) higher in TS patients (15.8%) than in CAD controls (11.5%), respectively, higher (P = 0.028) than in controls without CAD (11.1%). There were no differences between the groups in cumulative incidence of cancer after the index event but a higher mortality in TS patients who developed cancer when compared with controls without CAD that developed cancer after the index event (P = 0.018).

CONCLUSIONS

There is an increased prevalence of first diagnosed cancer in TS patients before the index event but no increased cumulative incidence of cancer after the index event. The results does not support investigation for the possibility of a malignancy specifically in TS patients but in the event of cancer this patient group might need special care. However, if there is lack of a clear stressor it could be of importance to investigate the possibility of a malignancy.

P6599Upregulation of protein and gene expression of arginase-1 in patients with ST elevation myocardial infarction

Background

The mechanisms underlying rupture of a coronary atherosclerotic plaque and development of myocardial ischemia-reperfusion injury in ST-elevation myocardial infarction (STEMI) remain unknown. Increased arginase-1 activity leads to reduced nitric oxide production and increased formation of reactive oxygen species due to uncoupling of the endothelial nitric oxide synthase (eNOS). These events lead to endothelial dysfunction, plaque instability and increased susceptibility to ischemia-reperfusion injury in acute myocardial infarction. Experimental studies have shown that arginase-1 expression and activity are increased in atherosclerosis and during myocardial ischemia-reperfusion. Accordingly, inhibition of arginase-1 reduces atherosclerotic lesion development and limits the extent of infarct size during ischemia-reperfusion via an eNOS-dependent mechanism. Furthermore, arginase-1 inhibition improves endothelial function in patients with coronary artery disease but the potential role of arginase-1 in patients with STEMI is poorly understood.

Purpose

The purpose of the current study was to test the hypothesis that arginase-1 is upregulated and correlate to infarct size in STEMI patients.

Methods and results

Two independent cohorts of STEMI patients were included. In cohort 1, plasma and buffy coat leukocytes were collected from 53 STEMI patients at the time of arterial puncture for percutaneous coronary intervention, at 24–48 hours post STEMI and at 3 months post STEMI. Gene expression in leukocytes was determined in 51 patients with Affymetrix Human Transcriptome Array 2.0. In cohort 2, plasma was collected from 82 STEMI patients at admission and at 6 months for determination of plasma arginase-1. These patients underwent cardiac magnetic resonance imaging performed at day 4–7 and at 6 months post STEMI. Plasma arginase-1 levels were quantified with ELISA. Control blood samples were collected from 56 healthy age matched subjects. In cohort 1, ARG1 gene expression was four-fold higher in STEMI patients at admission compared to controls (Figure A). This expression returned to control levels within 3 months. Plasma arginase-1 levels were two times higher in STEMI patients at admission compared to controls, and remained elevated at 24–48 hours and at 3 months post STEMI (Figure B). The increase in plasma arginase-1 in STEMI patients was confirmed in cohort 2 (Figure C). Arginase-1 levels did not correlate with infarct size.

Conclusions

STEMI patients demonstrate increased gene expression and plasma levels of arginase-1 in the acute setting. In contrast to gene expression plasma arginase-1 levels remain significantly elevated over time. The markedly increased expression of arginase-1 already at admission may suggest a mechanistic role of arginase-1 in the development of STEMI. Further studies are needed to elucidate whether increased expression, induction and activity of arginase-1 are contributing factors for the development of STEMI.

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.

Trigger factors in takotsubo syndrome - A systematic review of case reports

INTRODUCTION

Takotsubo syndrome is an acute heart failure syndrome often preceded by a trigger factor of physical or emotional origin, although the proportion is unclear. The aim of the present study was to determine how common different trigger factors are in takotsubo syndrome divided by sex and age in women.

MATERIAL AND METHODS

The study consisted of a systematic review of all available case reports in PubMed and Web of Science up to March 2018. Trigger factors were categorized into physical and emotional trigger factors.

RESULTS

Males had to a higher degree experienced a trigger factor (92.6%) compared to females (81.9%, p < .001). Physical trigger factors were most common (67.3%). Males had to a higher degree experienced a physical trigger factor (85.7%) compared to females (63.5%, p < .001). Females ≤50 years of age had to a higher degree experienced a trigger factor (90.8%) compared to females >50 years of age (79.2%, p < .001). Additionally, females ≤50 years of age had to a higher degree experienced a physical trigger factor (75.6%) compared to females >50 years of age (59.3%, p < .01).

CONCLUSION

A physical trigger factor is more common than an emotional trigger factor in takotsubo syndrome. Physical triggers includes drugs, surgery and central nervous system conditions. Furthermore, females ≤50 years of age and males more often have an evident trigger factor and it is more often physical, compared to the most common patient, a female >50 years of age.

Takotsubo twins

Takotsubo syndrome is an intriguing condition of often stress induced reversible cardiac dysfunction mimicking myocardial infarction, but without explanatory coronary obstructions. The pathogenesis of the syndrome is not yet fully understood, though altered sympathetic regulation or response to cardiac sympathetic stimuli is likely to be involved. We present a unique and clinically detailed report of identical twin sisters, who both developed Takotsubo syndrome in association to mental stress shortly after menopause, also covering a potential relapse of disease in one of the twins, supporting the theory of a genetic contribution to the development of the syndrome proposed by previous case reports and small genetic studies.

Morbidity and cause-specific mortality in first-time myocardial infarction with nonobstructive coronary arteries

BACKGROUND

Myocardial infarction (MI) with nonobstructive coronary arteries (MINOCA) is receiving increasing interest as a prognostically adverse entity distinct from myocardial infarction with significant coronary artery disease (MI-CAD). However, data are still limited regarding long-term cardiovascular morbidity and cause-specific mortality in MINOCA.

METHODS

This is a registry-based cohort study using data from patients admitted to Swedish coronary care units. We investigated various nonfatal outcomes (recurrent MI, hospitalization for heart failure or stroke) and fatal outcomes (cardiovascular, respiratory or cancer-related mortality) in 4069 patients without apparent acute cardiovascular disease, used as non-MI controls, 7266 patients with first-time MINOCA and 69 267 patients with first-time MI-CAD.

RESULTS

Almost all event rates (median follow-up 3.8 years) increased in a stepwise fashion across the three cohorts [rates of major adverse events (MAE; composite of all-cause mortality, recurrent MI, hospitalization for heart failure or stroke): n = 268 (6.6%), n = 1563 (21.5%), n = 17 777 (25.7%), respectively]. Compared to non-MI controls, MINOCA patients had an adjusted hazard ratio (HR) of 2.12 (95% confidence interval 1.84-2.43) regarding MAE. MINOCA patients had a substantial risk of cardiovascular mortality and the highest numerical risks of respiratory and cancer-related mortality. Male sex, previous heart failure and chronic obstructive pulmonary disease had a stronger prognostic impact in MINOCA than in MI-CAD. Female MINOCA patients with atrial fibrillation were at particular risk.

CONCLUSIONS

Patients with first-time MINOCA have a considerable risk of adverse events. This stresses the need for a comprehensive search of the cause of MINOCA, thorough treatment of underlying disease triggers and close follow-up.

Reinfarction in Patients with Myocardial Infarction with Nonobstructive Coronary Arteries (MINOCA): Coronary Findings and Prognosis

BACKGROUND

Myocardial infarction (MI) with nonobstructive coronary arteries (MINOCA) is common. There are limited data on the mechanisms and prognosis for reinfarction in MINOCA patients.

METHODS

In this observational study of MINOCA patients hospitalized in Sweden and registered in the SWEDEHEART registry between July 2003 and June 2013 and followed until December 2013, we identified 9092 unique patients with MINOCA of 199,163 MI admissions in total. The 570 (6.3%) MINOCA patients who were hospitalized due to a recurrent MI constituted the study group.

RESULTS

The mean age was 69.1 years and 59.1% were women. The median time to readmission was 17 months. A total of 340 patients underwent a new coronary angiography and 180 (53%) had no obstructive coronary artery disease (CAD) and 160 (47%) had obstructive CAD; 123 had 1-vessel, 26 had 2-vessel, 9 had 3-vessel disease, and 2 had left main together with 1-vessel disease. Male sex, diabetes, peripheral vascular disease, higher levels of creatinine, and ST elevation at presentation were more common in patients with MI with obstructive CAD than in patients with a recurrent MINOCA. Mortality during a median follow-up of 38 months was similar whether the reinfarction event was MINOCA or MI with obstructive CAD 13.9% vs 11.9% (P = .54).

CONCLUSIONS

About half of patients with reinfarction after MINOCA who underwent coronary angiography had progression of coronary stenosis. Angiography should be strongly considered in patients with MI after MINOCA. Mortality associated with recurrent events was substantial, though there was no difference in mortality between those with or without significant CAD.

Personality Traits in Patients with Myocardial Infarction with Nonobstructive Coronary Arteries

OBJECTIVE

The purpose of this study was to describe type A behavior pattern and trait anger in patients with myocardial infarction with nonobstructive coronary arteries (MINOCA) and compare them with patients with coronary heart disease and healthy controls. Type A behavior pattern and anger have been linked to coronary heart disease in previous studies. This is the first study to assess type A behavior pattern and trait anger in MINOCA patients.

METHODS

One hundred MINOCA patients, consecutively recruited during 2007-2011 at 5 coronary care units in Stockholm, were matched for sex and age to 100 coronary heart disease patients and 100 healthy controls. All participants completed the Bortner Rating Scale to quantify type A behavior pattern and the Spielberger Trait Anger Scale to quantify anger 3 months after the acute event.

RESULTS

MINOCA patients' Bortner Rating Scale score was 70.9 ± 10.8 (mean ± SD) and Spielberger Trait Anger Scale score was 14 (12-17) (median; interquartile range). Coronary heart disease patients' Bortner Rating Scale score was 70.5 ± 10.2 and Spielberger Trait Anger Scale score was 14 (12-17). Healthy controls' Bortner Rating Scale score was 71.9 ± 9.1 and Spielberger Trait Anger Scale score was 13 (11-16).

CONCLUSION

We found no significant differences in Bortner Rating Scale score and Spielberger Trait Anger Scale score among MINOCA, coronary heart disease patients, and healthy controls, regardless of whether total scores, subscales, or cutoffs were used to classify type A behavior pattern and trait anger. However, we cannot exclude the existence of an occasional episode of anger or mental stress in relation to the coronary event. This is the first study to assess type A behavior pattern and trait anger in patients with MINOCA, and future studies need to confirm the current findings before any firm conclusions can be made.