A Single High-Sensitivity Cardiac Troponin T Strategy for Ruling Out Myocardial Infarction.

Background: Ruling out acute myocardial infarction (AMI) in the emergency department (ED) is challenging. Studies have shown that a high-sensitivity cardiac troponin T (hs-cTnT) <5 ng/L or <6 ng/L at presentation (0 h) can be used to rule out AMI. The objective of this study was to identify whether an even higher hs-cTnT threshold can be used for a safe rule out of AMI in the ED. Methods: The derivation cohort consisted of 24,973 ED patients with a primary complaint of chest pain. In this cohort, we identified the highest concentration of 0 h hs-cTnT that corresponded to a negative predictive value (NPV) of ≥99.5% for the primary endpoint of AMI/all-cause death within 30 days and the secondary endpoint of all-cause death within one year. The results were validated in two cohorts consisting of 132,021 and 1167 ED chest pain patients. Results: The 0 h hs-cTnT threshold corresponding to a NPV of ≥99.5% for the primary endpoint was <9 ng/L (NPV: 99.6% and 95% CI: 99.5-99.7). This cutoff provided a sensitivity of 96.2% (95% CI: 95.2-97.1) and identified 59.7% of the patients as low risk compared to 35.8% and 43.9% with a 0 h hs-cTnT <5 ng/L and <6 ng/L, respectively. The results were similar in the validation cohorts and seemed to perform even better in patients where the 0 h hs-cTnT was measured >3 h after symptom onset and in those with a nonischemic ECG and nonhigh risk history. Conclusions: A 0 h hs-cTnT cutoff of <9 ng/L safely rules out AMI/death within 30 days in a majority of chest pain patients and is a more effective strategy than the currently recommended <5 ng/L and <6 ng/L cutoffs. This trial is registered with NCT03421873.

Sex differences in potential triggers of myocardial infarction.

Aims: Internal and external triggers affect seasonal and circadian variations of myocardial infarction (MI). We aimed to assess sex differences in the common triggers of MI. Methods and results: A nationwide, retrospective, cross-sectional postal survey study was conducted. Individuals who experienced a MI during holidays and weekdays were identified through the SWEDEHEART registry. Twenty-seven potential MI triggers were rated in regards to occurring more or less than usual during the last 24 h before the MI. Three areas were covered: activities, emotions, and food or alcohol consumption. A logistic regression model was used to identify sex differences for each trigger and odds ratios (ORs) were reported. Four hundred and fifty-one patients, of whom 317 were men, responded. The most commonly reported triggers were stress (35.3%), worry (26.2%), depression (21.1%), and insomnia (20.0%). Women reported emotional triggers including sadness [OR 3.52, 95% confidence interval (CI) 1.92-6.45], stress (OR 2.38, 95% CI 1.52-3.71), insomnia (OR 2.31, 95% CI 1.39-3.81), and upset (OR 2.69, 95% CI 1.47-4.95) to a greater extent than men. Outdoor activity was less reported by women (OR 0.35, 95% CI 0.14-0.87). No significant sex differences were found in other activities or food and alcohol consumption. Conclusion: Self-experienced stress and distress were higher among women prior to MI compared with men. Understanding sex perspectives in acute triggers may help us find preventive strategies and reduce the excess numbers of MI.

On the Natural History of Coronary Artery Disease: A Longitudinal Nationwide Serial Angiography Study.

Background The long-term course of coronary atherosclerosis has not been studied in large nationwide cohorts. Understanding the natural history of coronary atherosclerosis could help identify patients at risk for future coronary events. Methods and Results All coronary artery segments with <50% luminal stenosis in patients with a first-time coronary angiogram between 1989 and 2017 were identified (n=2 661 245 coronary artery segments in 248 736 patients) and followed until a clinically indicated angiography within 15 years was performed or until death or end of follow-up (April 2018) using SCAAR (Swedish Coronary Angiography and Angioplasty Registry). The stenosis progression and incidence rates were 2.6% and 1.45 (95% CI, 1.43-1.46) per 1000 segment-years, respectively. The greatest progression rate occurred in the proximal and middle segments of the left anterior descending artery. Male sex and diabetes were associated with a 2-fold increase in risk, and nearly 70% of new stenoses occurred in patients with baseline single-vessel disease (hazard ratio, 3.86 [95% CI, 3.69-4.04]). Coronary artery segments in patients with no baseline risk factors had a progression rate of 0.6% and incidence rate of 0.36 (95% CI, 0.34-0.39), increasing to 8.1% and 4.01 (95% CI, 3.89-4.14) per 1000 segment-years, respectively, in patients with ≥4 risk factors. The prognostic impact of risk factors on stenosis progression was greatest in younger patients and women. Conclusions Coronary atherosclerosis progressed slowly but more frequently in the left coronary artery in men and in the presence of traditional risk factors. Coronary artery segments in patients without risk factors had little or no risk of stenosis progression, and the relative impact of risk factors appears to be of greater importance in younger patients and women. These findings help in the understanding the long-term course of coronary atherosclerosis.

Pretreatment with heparin in patients with ST-segment elevation myocardial infarction: a report from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR).

BACKGROUND: Unfractionated heparin (UFH) is frequently administered before percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI). AIMS: The aim of the study was to investigate if pretreatment with UFH prior to arrival at the catheterisation laboratory affects coronary artery occlusion, mortality, and in-hospital major bleeding in patients with STEMI undergoing PCI. METHODS: Patients with a first STEMI event undergoing PCI between 2008 and 2016 were extracted from the Swedish Coronary Angiography and Angioplasty Registry. Risk ratios for UFH pretreatment versus no pretreatment regarding coronary artery occlusion at presentation in the catheterisation laboratory, 30-day mortality, and bleeding were obtained using adjusted Poisson regression models with robust standard errors. Analyses of propensity score (PS)-matched groups were performed to obtain absolute risk differences. RESULTS: In all, 41,631 patients were included, 16,026 (38%) with and 25,605 (62%) without UFH pretreatment. Adjusted risk ratios were 0.89 (95% confidence interval [CI]: 0.87 to 0.90) for coronary artery occlusion, 0.87 (0.77 to 0.99) for mortality, and 1.01 (0.86 to 1.18) for bleeding. In the PS-matched analyses, the absolute risk differences were -0.087 (-0.074 to -0.099) for coronary artery occlusion, -0.011 (-0.017 to -0.0041) for mortality, and 0 (-0.0052 to 0.0052) for bleeding. CONCLUSIONS: Pretreatment with UFH was associated with a reduction in coronary artery occlusion among patients with STEMI, with a number needed to treat (NNT) of 12, without increasing the risk of major in-hospital bleeding. Regarding mortality, a reduction was found with UFH pretreatment, with an NNT of 94, but this effect was not robust over all sensitivity analyses and residual confounding cannot be excluded.

Trends in Clinical Practice and Outcomes After Percutaneous Coronary Intervention of Unprotected Left Main Coronary Artery.

Background The use of percutaneous coronary intervention (PCI) to treat unprotected left main coronary artery disease has expanded rapidly in the past decade. We aimed to describe nationwide trends in clinical practice and outcomes after PCI for left main coronary artery disease. Methods and Results Patients (n=4085) enrolled in the SCAAR (Swedish Coronary Angiography and Angioplasty Registry) as undergoing PCI for left main coronary artery disease from 2005 to 2017 were included. A count regression model was used to analyze time-related differences in procedural characteristics. The 3-year major adverse cardiovascular and cerebrovascular event rate defined as death, myocardial infarction, stroke, and repeat revascularization was calculated with the Kaplan-Meier estimator and Cox proportional hazard model. The number of annual PCI procedures grew from 121 in 2005 to 589 in 2017 (389%). The increase was greater for men (479%) and individuals with diabetes (500%). Periprocedural complications occurred in 7.9%, decreasing from 10% to 6% during the study period. A major adverse cardiovascular and cerebrovascular event occurred in 35.7% of patients, falling from 45.6% to 23.9% (hazard ratio, 0.56; 95% CI, 0.41-0.78; P=0.001). Radial artery access rose from 21.5% to 74.2% and intracoronary diagnostic procedures from 14.0% to 53.3%. Use of bare-metal stents and first-generation drug-eluting stents fell from 19.0% and 71.9%, respectively, to 0, with use of new-generation drug-eluting stents increasing to 95.2%. Conclusions Recent changes in clinical practice relating to PCI for left main coronary artery disease are characterized by a 4-fold rise in procedures conducted, increased use of evidence-based adjunctive treatment strategies, intracoronary diagnostics, newer stents, and more favorable outcomes.

Adding historical high-sensitivity troponin T results to rule out acute myocardial infarction.

AIMS: The clinical usefulness of historical concentrations of high-sensitivity cardiac troponin T (hs-cTnT) is unknown. This study investigated the ability to rule out myocardial infarction (MI) with the use of historical hs-cTnT concentrations among patients with chest pain in the emergency department (ED). METHODS AND RESULTS: The derivation cohort consisted of patients presenting with chest pain to nine different EDs (n = 60 071), where we included those with ≥1 hs-cTnT analysed at the index visit and ≥1 hs-cTnT results prior to the visit. We developed an algorithm to rule out MI within 30 days with a pre-specified target negative predictive value (NPV) of ≥99.5%. The performance was then validated in a separate cohort of ED chest pain patients (n = 10 994). A historical hs-cTnT < 12 ng/L and a < 3 ng/L absolute change between the historical and the index visit hs-cTnT had the best performance and ruled out 24 862 (41%) patients in the derivation cohort. In the validation cohort, these criteria identified 4764 (43%) low-risk patients in whom 18 (0.4%) MIs within 30 days occurred, and had an NPV for MI of 99.6% (99.4-99.8), a sensitivity of 96.9% (95.2-.2), and an LR- of 0.11 (0.07-0.14). CONCLUSION: Combining a historical hs-cTnT with a single new hs-cTnT may safely rule out MI and thereby reduce the need for serial hs-cTnT measurements in ED patients with chest pain.

Safety of early hospital discharge following admission with ST-elevation myocardial infarction treated with percutaneous coronary intervention: a nationwide cohort study.

BACKGROUND: The Second Primary Angioplasty in Myocardial Infarction (PAMI-II) risk score is recommended by guidelines to identify low-risk patients with ST-elevation myocardial infarction (STEMI) for an early discharge strategy. AIMS: We aimed to assess the safety of early discharge (≤2 days) for low-risk STEMI patients treated with primary percutaneous coronary intervention (PCI). METHODS: Using nationwide data from the SWEDEHEART registry, we identified patients with STEMI treated with primary PCI during the period 2009-2017, of whom 8,092 (26.4%) were identified as low risk with the PAMI-II score. Low-risk patients were stratified according to their length of hospital stay (≤2 days vs >2 days). The primary endpoint was major adverse cardiovascular events (MACE, including death, reinfarction treated with PCI, stroke or heart failure hospitalisation) at one year, assessed using a Cox proportional hazards model with propensity score as well as an inverse probability weighting propensity score of average treatment effect to adjust for confounders. RESULTS: A total of 1,449 (17.9%) patients were discharged ≤2 days from admission. After adjustment, the one-year MACE rate was not higher for patients discharged at >2 days from admission than for patients discharged ≤2 days (4.3% vs 3.2%; adjusted HR 1.31, 95% confidence interval [CI]: 0.92-1.87, p=0.14), and no difference was observed regarding any of the individual components of the main outcome. Results were consistent across all subgroups with no difference in MACE between early and late discharge patients. CONCLUSIONS: Nationwide observational data suggest that early discharge of low-risk patients with STEMI treated with PCI is not associated with an increase in one-year MACE.

Development and validation of an artificial neural network algorithm to predict mortality and admission to hospital for heart failure after myocardial infarction: a nationwide population-based study.

BACKGROUND: Patients have an estimated mortality of 15-20% within the first year following myocardial infarction and one in four patients who survive myocardial infarction will develop heart failure, severely reducing quality of life and increasing the risk of long-term mortality. We aimed to establish the accuracy of an artificial neural network (ANN) algorithm in predicting 1-year mortality and admission to hospital for heart failure after myocardial infarction. METHODS: In this nationwide population-based study, we used data for all patients admitted to hospital for myocardial infarction and discharged alive from a coronary care unit in Sweden (n=139 288) between Jan 1, 2008, and April 1, 2017, from the Swedish Web system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies (SWEDEHEART) nationwide registry; these patients were randomly divided into training (80%) and testing (20%) datasets. We developed an ANN using 21 variables (including age, sex, medical history, previous medications, in-hospital characteristics, and discharge medications) associated with the outcomes of interest with a back-propagation algorithm in the training dataset and tested it in the testing dataset. The ANN algorithm was then validated in patients with incident myocardial infarction enrolled in the Western Denmark Heart Registry (external validation cohort) between Jan 1, 2008, and Dec 31, 2016. The predictive ability of the model was evaluated using area under the receiver operating characteristic curve (AUROC) and Youden's index was established as a means of identifying an empirical dichotomous cutoff, allowing further evaluation of model performance. FINDINGS: 139 288 patients who were admitted to hospital for myocardial infarction in the SWEDEHEART registry were randomly divided into a training dataset of 111 558 (80%) patients and a testing dataset of 27 730 (20%) patients. 30 971 patients with myocardial infarction who were enrolled in the Western Denmark Heart Registry were included in the external validation cohort. A first event, either all-cause mortality or admission to hospital for heart failure 1 year after myocardial infarction, occurred in 32 308 (23·2%) patients in the testing and training cohorts only. For 1-year all-cause mortality, the ANN had an AUROC of 0·85 (95% CI 0·84-0·85) in the testing dataset and 0·84 (0·83-0·84) in the external validation cohort. The AUROC for admission to hospital for heart failure within 1 year was 0·82 (0·81-0·82) in the testing dataset and 0·78 (0·77-0·79) in the external validation dataset. With an empirical cutoff the ANN algorithm correctly classified 73·6% of patients with regard to all-cause mortality and 61·5% of patients with regard to admission to hospital for heart failure in the external validation cohort, ruling out adverse outcomes with 97·1-98·7% probability in the external validation cohort. INTERPRETATION: Identifying patients at a high risk of developing heart failure or death after myocardial infarction could result in tailored therapies and monitoring by the allocation of resources to those at greatest risk. FUNDING: The Swedish Heart and Lung Foundation, Swedish Scientific Research Council, Swedish Foundation for Strategic Research, Knut and Alice Wallenberg Foundation, ALF Agreement on Medical Education and Research, Skane University Hospital, The Bundy Academy, the Märta Winkler Foundation, the Anna-Lisa and Sven-Eric Lundgren Foundation for Medical Research.

Validation of the 4-Item PRECISE-DAPT Score: A SWEDEHEART Study.

Background The Predicting Bleeding Complications in Patients Undergoing Stent Implantation and Subsequent Dual Antiplatelet Therapy (PRECISE-DAPT) score has been shown to predict out-of-hospital major bleeding after myocardial infarction treated with percutaneous coronary intervention and dual antiplatelet therapy (DAPT). However, large validation studies have been scarce and the discriminative ability for patients with a preexisting bleeding risk factor (elderly, underweight, women, anemia, kidney dysfunction, or cancer) in a real-world setting is unknown. Methods and Results Patients undergoing percutaneous coronary intervention for myocardial infarction between 2008 and 2017 were included from the SWEDEHEART (Swedish Web System for Enhancement of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies) registry (n=66 295). The predictive value of the PRECISE-DAPT score for rehospitalization with major bleeding during dual antiplatelet therapy was evaluated using receiver operating characteristic analyses. A high PRECISE-DAPT score (≥25; n=13 894) was associated with increased risk of major bleeding (3.9% versus 1.8%; hazard ratio [HR], 2.2; 95% CI, 2.0-2.5; P<0.001) compared with a non-high score (<25; n=52 401). The score demonstrated a c-statistic of 0.64 (95% CI, 0.63-0.66). The discriminative ability of the score to further stratify bleeding risk in patients with preexisting bleeding risk factors was poor, especially in patients who are elderly (c-statistic=0.57; 95% CI, 0.55-0.60) or underweight (c-statistic=0.56; 95% CI, 0.51-0.61), for whom a non-high PRECISE-DAPT score was associated with similar bleeding risk as a high PRECISE-DAPT score in the general myocardial infarction population. Conclusions In this nationwide population-based study, the PRECISE-DAPT score performed moderately in the general myocardial infarction population and poorly in patients with preexisting bleeding risk factors, where its usefulness seems limited.

Clinical Impact of Intraprocedural Stent Thrombosis During Percutaneous Coronary Intervention in Patients Treated With Potent P2Y12 inhibitors - a VALIDATE-SWEDEHEART Substudy.

Background The clinical importance of intraprocedural stent thrombosis (IPST) during percutaneous coronary intervention in the contemporary era of potent oral P2Y12 inhibitors is not established. The aim of this study was to assess IPST and its association with clinical outcome in patients with myocardial infarction undergoing percutaneous coronary intervention with contemporary antithromboticmedications. Methods and Results The VALIDATE-SWEDEHEART study (Bivalirudin Versus Heparin in ST-Segment and Non-ST-Segment Elevation Myocardial Infarction in Patients on Modern Antiplatelet Therapy in the Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies Registry Trial) included 6006 patients with myocardial infarction, treated with potent P2Y12 inhibitors during percutaneous coronary intervention. IPST, defined as a new or worsening thrombus related to a stent deployed during the procedure, was reported by the interventional cardiologist in 55 patients (0.9%) and was significantly associated with ST-segment elevation myocardial infarction presentation, longer stents, bailout glycoprotein IIb/IIIa inhibitors, and final Thrombolysis in Myocardial Infarction flow <3. The primary composite end point included cardiovascular death, myocardial infarction, out-of-laboratory definite stent thrombosis and target vessel revascularization within 30 days. Secondary end points were major bleeding and the individual components of the primary composite end point. Patients with versus without IPST had significantly higher rates of the primary composite end point (20.0% versus 4.4%), including higher rates of cardiovascular death, target vessel revascularization, and definite stent thrombosis, but not myocardial infarction or major bleeding. By multivariable analysis, IPST was independently associated with the primary composite end point (hazard ratio, 3.82; 95% CI, 2.05-7.12; P<0.001). Conclusions IPST is a rare but dangerous complication during percutaneous coronary intervention, independently associated with poor prognosis, even in the current era of potent antiplatelet agents. Future treatment studies are needed to reduce the rate of IPST and to improve the poor outcome among these patients. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02311231.

Christmas holiday triggers of myocardial infarction.

Objectives: Christmas holidays have been associated with the highest incidence of myocardial infarction (MI). We wanted to assess possible triggers of MI during Christmas. Design: A nationwide, retrospective postal survey with case-control design. All individuals suffering an MI during the Christmas holidays 2018 and 2019 in Sweden were identified through the SWEDEHEART registry and a control group matched in age and gender with chronic coronary syndrome who did not seek medical attention during Christmas were asked for participation. Subjects completed a questionnaire asking them to rate 27 potential MI-triggers as having occurred more or less than usual. Results: A total of 189 patients suffering an MI on Christmas Eve, Christmas Day, or Boxing Day, and 157 patients in the control group responded to the questionnaire, representing response rates of 66% and 62%, respectively. Patients with MI on Christmas experienced more stress (37% vs. 21%, p = .002), depression (21% vs. 11%, p = .024), and worry (26% vs. 10%, p < .001) compared to the control group. The food and sweets consumption was increased in both groups, but to a greater extent in the control group (33% vs. 50%, p = .002 and 32% vs. 43%, p = .031). There were no increases in quarrels, anger, economic worries, or reduced compliance with medication. Conclusions: Patients suffering MI on Christmas holiday experienced higher levels of stress and emotional distress compared to patients with chronic coronary syndrome, possibly contributing to the phenomenon of holiday heart attack. Understanding what factors increase the number of MI on Christmas may help reduce the excess number of MIs and cardiovascular burden.

Prevalence of Subclinical Coronary Artery Atherosclerosis in the General Population.

BACKGROUND: Early detection of coronary atherosclerosis using coronary computed tomography angiography (CCTA), in addition to coronary artery calcification (CAC) scoring, may help inform prevention strategies. We used CCTA to determine the prevalence, severity, and characteristics of coronary atherosclerosis and its association with CAC scores in a general population. METHODS: We recruited 30 154 randomly invited individuals age 50 to 64 years to SCAPIS (the Swedish Cardiopulmonary Bioimage Study). The study includes individuals without known coronary heart disease (ie, no previous myocardial infarctions or cardiac procedures) and with high-quality results from CCTA and CAC imaging performed using dedicated dual-source CT scanners. Noncontrast images were scored for CAC. CCTA images were visually read and scored for coronary atherosclerosis per segment (defined as no atherosclerosis, 1% to 49% stenosis, or ≥50% stenosis). External validity of prevalence estimates was evaluated using inverse probability for participation weighting and Swedish register data. RESULTS: In total, 25 182 individuals without known coronary heart disease were included (50.6% women). Any CCTA-detected atherosclerosis was found in 42.1%; any significant stenosis (≥50%) in 5.2%; left main, proximal left anterior descending artery, or 3-vessel disease in 1.9%; and any noncalcified plaques in 8.3% of this population. Onset of atherosclerosis was delayed on average by 10 years in women. Atherosclerosis was more prevalent in older individuals and predominantly found in the proximal left anterior descending artery. Prevalence of CCTA-detected atherosclerosis increased with increasing CAC scores. Among those with a CAC score >400, all had atherosclerosis and 45.7% had significant stenosis. In those with 0 CAC, 5.5% had atherosclerosis and 0.4% had significant stenosis. In participants with 0 CAC and intermediate 10-year risk of atherosclerotic cardiovascular disease according to the pooled cohort equation, 9.2% had CCTA-verified atherosclerosis. Prevalence estimates had excellent external validity and changed marginally when adjusted to the age-matched Swedish background population. CONCLUSIONS: Using CCTA in a large, random sample of the general population without established disease, we showed that silent coronary atherosclerosis is common in this population. High CAC scores convey a significant probability of substantial stenosis, and 0 CAC does not exclude atherosclerosis, particularly in those at higher baseline risk.

Using proximity extension proteomics assay to identify biomarkers associated with infarct size and ejection fraction after ST-elevation myocardial infarction.

Plasma concentrations of many cardiovascular and inflammatory proteins are altered after ST-elevation myocardial infarction (STEMI) and may provide prognostic information. We conducted a large-scale proteomic analysis in patients with STEMI, correlating protein levels to infarct size and left ventricular ejection fraction (LVEF) determined with cardiac magnetic resonance imaging. We analysed 131 cardiovascular and inflammatory proteins using a multiplex proximity extension assay and blood samples obtained at baseline, 6, 24, and 96 h from the randomised clinical trial CHILL-MI. Cardiac magnetic resonance imaging data at 4 ± 2 days and 6 months were available as per trial protocol. Using a linear regression model with bootstrap resampling and false discovery rate adjustment we identified five proteins (ST2, interleukin-6, pentraxin-3, interleukin-10, renin, and myoglobin) with elevated values corresponding to larger infarct size or worse LVEF and four proteins (TNF-related apoptosis-inducing ligand, TNF-related activation induced cytokine, interleukin-16, and cystatin B) with values inversely related to LVEF and infarct size, concluding that among 131 circulating inflammatory and cardiovascular proteins in the acute and sub-acute phase of STEMI, nine showed a relationship with infarct size and LVEF post-STEMI, with IL-6 and ST2 exhibiting the strongest association.

Incidence and outcome of myocardial infarction treated with percutaneous coronary intervention during COVID-19 pandemic.

OBJECTIVE: Most reports on the declining incidence of myocardial infarction (MI) during the COVID-19 have either been anecdotal, survey results or geographically limited to areas with lockdowns. We examined the incidence of MI during the COVID-19 pandemic in Sweden, which has remained an open society with a different public health approach fighting COVID-19. METHODS: We assessed the incidence rate (IR) as well as the incidence rate ratios (IRRs) of all MI referred for coronary angiography in Sweden using the nationwide Swedish Coronary Angiography and Angioplasty Registry (SCAAR), during the COVID-19 pandemic in Sweden (1 March 2020-7 May 2020) in relation to the same days 2015-2019. RESULTS: A total of 2443 MIs were referred for coronary angiography during the COVID-19 pandemic resulting in an IR 36 MIs/day (204 MIs/100 000 per year) compared with 15 213 MIs during the reference period with an IR of 45 MIs/day (254 MIs/100 000 per year) resulting in IRR of 0.80, 95% CI (0.74 to 0.86), p<0.001. Results were consistent in all investigated patient subgroups, indicating no change in patient category seeking cardiac care. Kaplan-Meier event rates for 7-day case fatality were 439 (2.3%) compared with 37 (2.9%) (HR: 0.81, 95% CI (0.58 to 1.13), p=0.21). Time to percutaneous coronary intervention (PCI) was shorter during the pandemic and PCI was equally performed, indicating no change in quality of care during the pandemic. CONCLUSION: The COVID-19 pandemic has significantly reduced the incidence of MI referred for invasive treatment strategy. No differences in overall short-term case fatality or quality of care indicators were observed.

Usefulness of High Sensitivity Troponin T to Predict Long-Term Left Ventricular Dysfunction After ST-Elevation Myocardial Infarction.

Guidelines recommend the use of transthoracic echocardiography (TTE) and clinical scores to risk stratify patients after ST-elevation myocardial infarction (STEMI). High sensitivity troponin T (hs-cTnT) is predictive of outcome after STEMI but the predictive value of hs-cTnT relative to other risk assessment tools has not been established. We aimed to compare the predictive value of hs-cTnT to other risk assessment tools in patients with STEMI. A subset of 578 patients with STEMI were included in this post-hoc study from the Third DANish Study of Optimal Acute Treatment of Patients with ST-segment Elevation Myocardial Infarction trial. Patients underwent cardiac magnetic resonance imaging (CMR) during index hospitalization as well as TTE at 1 year after their STEMI. The predictive value of hs-cTnT was compared with CKMB, infarct size (IS)/left ventricular ejection fraction (LVEF) assessed with CMR, LVEF assessed at discharge with TTE and the Global Registry of Acute Coronary Events (GRACE) and Thrombolysis in Myocardial Infarction (TIMI) risk-scores. The primary outcome was LV systolic dysfunction defined as LVEF ≤40% after 1 year on TTE. The area under the receiver operating characteristic curve analyses showed no significant difference between hs-cTnT and early CMR-assessed IS or LVEF in predicting subsequent LVEF ≤40%. Area under the curve for hs-cTnT was 0.82, 0.85 for IS (p = 0.22), and 0.87 for LVEF (p = 0.23). For predischarge TTE-assessed LVEF, the value was 0.85 (p = 0.45), 0.63 for creatine kinase-MB (p <0.001), 0.61 for the GRACE score (p <0.001), and 0.70 for the TIMI score (p = 0.02). A peak hs-cTnT value <3,500 ng/L ruled out LVEF ≤40% with probability of 98%. In conclusion, in patients presenting with STEMI undergoing PCI, hs-cTnT level strongly predicted long-term LV dysfunction and could be used as a clinical risk stratification tool to identify patients at high risk of progressing to LV dysfunction due to its general availability and high-predictive accuracy.

Association of acute myocardial infarction with influenza: A nationwide observational study.

INTRODUCTION: Influenza may precipitate cardiovascular disease, but influenza typically peaks in winter, coinciding with other triggers of myocardial infarction (MI) such as low air temperature, high wind velocity, low atmospheric pressure, and short sunshine duration. OBJECTIVE: We aimed to determine the relationship of week-to-week variation in influenza cases and acute MI, controlling for meteorological factors in a nationwide population. METHODS: Weekly laboratory-confirmed influenza case reports were obtained from the Public Health Agency of Sweden from 2009 to 2016 and merged with the nationwide SWEDEHEART MI registry. Weekly incidence of MI was studied with regard to number of influenza cases stratified into tertiles of 0-16, 17-164, and >164 cases/week. Incidence rate ratios (IRR) were calculated using a count regression model for each category and compared to a non-influenza period as reference, controlling for air temperature, atmospheric pressure, wind velocity, and sunshine duration. RESULTS: A total of 133562 MI events was reported to the registry during the study period. Weeks with influenza cases were associated with higher incidence of MI than those without in unadjusted analysis for overall MI, ST-elevation MI and non ST-elevation MI independently. During the influenza season, weeks with 0-16 reported cases/week were not associated with MI incidence after adjusting for weather parameters, adjusted IRR for MI was 1.03 (95% CI 1.00-1.06, P = 0.09). However, weeks with more cases reported were associated with MI incidence: 17-163 reported cases/week, adjusted IRR = 1.05 (95% CI 1.02-1.08, P = 0.003); and for ≥164 cases/week, the IRR = 1.06 (95% CI 1.02-1.09, P = 0.002). Results were consistent across a large range of subgroups. CONCLUSIONS: In this nationwide observational study, we found an association of incidence of MI with incidence of influenza cases beyond what could be explained by meteorological factors.

Bivalirudin Versus Heparin Monotherapy in Elderly Patients With Myocardial Infarction: A Prespecified Subgroup Analysis of the VALIDATE-SWEDEHEART Trial.

BACKGROUND: Elderly patients with acute myocardial infarction undergoing percutaneous coronary intervention are at increased risk of both ischemic and bleeding complications. The optimal anticoagulation strategy in these patients is uncertain. Therefore, we compared bivalirudin to heparin monotherapy in a contemporary cohort of such patients. METHODS: A prespecified subgroup analysis of elderly patients with myocardial infarction (≥75 years) from the VALIDATE-SWEDEHEART trial (Bivalirudin Versus Heparin in ST-Segment and Non-ST-Segment Elevation Myocardial Infarction in Patients on Modern Antiplatelet Therapy in the Swedish Web System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies Registry Trial) was performed. In the trial, patients were randomized to either bivalirudin or heparin monotherapy during percutaneous coronary intervention, with mandatory potent P2Y12 inhibition, routine radial artery access, and only bail-out glycoprotein IIb/IIIa inhibition. Kaplan-Meier event rates were assessed for the primary end point, consisting of a composite of all-cause death, myocardial reinfarction, or major bleeding, within 180 days. RESULTS: The elderly (n=1592) had more than twice the risk of all events compared with younger patients (n=4406). Baseline and periprocedural characteristics were equal between bivalirudin (n=799) and heparin (n=793) treated patients ≥75 years. No differences were found in the elderly between bivalirudin and heparin monotherapy regarding the primary end point (180-day all-cause death, myocardial reinfarction, or major bleeding), the individual components of the primary end point, definite stent thrombosis, or stroke. CONCLUSIONS: In this prespecified subgroup analysis of the VALIDATE-SWEDEHEART trial, elderly patients with myocardial infarction had a highly increased risk of all events. However, no difference in outcomes could be observed with an anticoagulation strategy with either bivalirudin or heparin as monotherapy in this patient group.

Circadian onset and prognosis of myocardial infarction with non-obstructive coronary arteries (MINOCA).

BACKGROUND: Many acute cardiovascular events such as myocardial infarction (MI) follow circadian rhythms. Myocardial infarction with non-obstructive coronary arteries (MINOCA) is a newly noticed entity with limited data on onset pattern and its impact on prognosis. MATERIAL AND METHODS: In this observational study of Swedish MINOCA patients registered in the SWEDEHEART registry between 2003-2013 and followed until December 2013 we identified 9,092 unique patients with MINOCA out of 199,163 MI admissions in total. Incidence rate ratios (IRR) were calculated for whole hours, parts of the day, weekdays, months, seasons and major holidays. RESULTS: The mean age was 65.5 years, 62.0% were women and 16.6% presented with STEMI. The risk for MINOCA proved to be most common in the morning (IRR = 1.70, 95% CI [1.63-1.84]) with a peak at 08.00 AM (IRR = 2.25, 95% CI [1.96-2.59]) and on Mondays (IRR = 1.28, 95% CI [1.18-1.38]). No altered risk was detected during the different seasons, the Christmas and New Year holidays or the Swedish Midsummer festivities. There was no association between time of onset of MINOCA and short- or long-term prognosis. CONCLUSION: The onset of MINOCA shows a circadian and circaseptan variation with increased risk at early mornings and Mondays, similar to previous studies on all MI, suggesting stress related triggering. However, during holidays were traditional MI increase, we did not see any increase for MINOCA. No association was detected between time of onset and prognosis, indicating that the underlying pathological mechanisms of MINOCA and the quality of care are similar at different times of onset but triggering mechanism may be more active early mornings and Mondays.

Editor's Choice- Heparin pre-treatment in patients with ST-segment elevation myocardial infarction and the risk of intracoronary thrombus and total vessel occlusion. Insights from the TASTE trial.

BACKGROUND:: Pre-treatment with unfractionated heparin is common in ST-segment elevation myocardial infarction (STEMI) protocols, but the effect on intracoronary thrombus burden is unknown. We studied the effect of heparin pre-treatment on intracoronary thrombus burden and Thrombolysis in Myocardial Infarction (TIMI) flow prior to percutaneous coronary intervention in patients with STEMI. METHODS:: The Thrombus Aspiration in ST-Elevation Myocardial Infarction in Scandinavia (TASTE) trial angiographically assessed intracoronary thrombus burden and TIMI flow, prior to percutaneous coronary intervention, in patients with STEMI. In this observational sub-study, patients pre-treated with heparin were compared with patients not pre-treated with heparin. Primary end points were a visible intracoronary thrombus and total vessel occlusion prior to percutaneous coronary intervention. Secondary end points were in-hospital bleeding, in-hospital stroke and 30-day all-cause mortality. RESULTS:: Heparin pre-treatment was administered in 2898 out of 7144 patients (41.0%). Patients pre-treated with heparin less often presented with an intracoronary thrombus (61.3% vs. 66.0%, p<0.001) and total vessel occlusion (62.9% vs. 71.6%, p<0.001). After adjustments, heparin pre-treatment was independently associated with a reduced risk of intracoronary thrombus (odds ratio (OR) 0.73, 95% confidence interval (CI)=0.65-0.83) and total vessel occlusion (OR 0.64, 95% CI=0.56-0.73), prior to percutaneous coronary intervention. There were no significant differences in secondary end points of in-hospital bleeding (OR 0.84, 95% CI=0.55-1.27), in-hospital stroke (OR 1.17, 95% CI=0.48-2.82) or 30-day all-cause mortality (hazard ratio 0.88, 95% CI=0.60-1.30). CONCLUSIONS:: Heparin pre-treatment was independently associated with a lower risk of intracoronary thrombus and total vessel occlusion before percutaneous coronary intervention in patients with STEMI, without evident safety concerns, in this large multi-centre observational study.