Importance of hospital and clinical factors for early mortality in Takotsubo syndrome: Insights from the Swedish Coronary Angiography and Angioplasty Registry.

BACKGROUND: Takotsubo syndrome (TTS) is an acute heart failure syndrome with symptoms similar to acute myocardial infarction. TTS is often triggered by acute emotional or physical stress and is a significant cause of morbidity and mortality. Predictors of mortality in patients with TS are not well understood, and there is a need to identify high-risk patients and tailor treatment accordingly. This study aimed to assess the importance of various clinical factors in predicting 30-day mortality in TTS patients using a machine learning algorithm. METHODS: We analyzed data from the nationwide Swedish Coronary Angiography and Angioplasty Registry (SCAAR) for all patients with TTS in Sweden between 2015 and 2022. Gradient boosting was used to assess the relative importance of variables in predicting 30-day mortality in TTS patients. RESULTS: Of 3,180 patients hospitalized with TTS, 76.0% were women. The median age was 71.0 years (interquartile range 62-77). The crude all-cause mortality rate was 3.2% at 30 days. Machine learning algorithms by gradient boosting identified treating hospitals as the most important predictor of 30-day mortality. This factor was followed in significance by the clinical indication for angiography, creatinine level, Killip class, and age. Other less important factors included weight, height, and certain medical conditions such as hyperlipidemia and smoking status. CONCLUSIONS: Using machine learning with gradient boosting, we analyzed all Swedish patients diagnosed with TTS over seven years and found that the treating hospital was the most significant predictor of 30-day mortality.

Dual antithrombotic treatment in chronic coronary syndrome: European Society of Cardiology criteria vs. CHADS-P2A2RC score.

AIMS: According to the 2019 European Society of Cardiology (ESC) guidelines on chronic coronary syndromes (CCS), adding a P2Y12 inhibitor or rivaroxaban to aspirin should be considered in high-risk patients. We estimated the proportion of patients eligible for treatment with the ESC criteria and examined if a recently validated risk score (CHADS-P2A2RC) could improve risk prediction. METHODS AND RESULTS: We included 61 338 CCS patients undergoing first-time coronary angiography in Western Denmark (2003-16) and classified them according to the ESC criteria and the CHADS-P2A2RC score. The ESC criteria identified 33.9% as high risk, 53.3% as moderate risk, and 12.8% as low risk. The CHADS-P2A2RC score identified 24.9% as high risk (≥4 points), 48.1% as moderate risk (2-3 points), and 27.0% as low risk (≤1 points). Major adverse cardiovascular events per 100 person-years were 4.8 [95% confidence interval (CI) 4.6-5.0] in patients considered high risk with both schemes, 2.1 (95% CI 2.0-2.2) in patients considered high risk with the ESC but low-to-moderate risk with the CHADS-P2A2RC criteria, 3.8 (95% CI 3.6-4.1) in patients considered low-to-moderate risk with the ESC but high risk with the CHADS-P2A2RC criteria, and 1.5 (95% CI 1.5-1.6) in patients considered low-to-moderate risk with both schemes. The CHADS-P2A2RC score enabled correct downward risk reclassification of 5161 patients (8%) without events, yielding an improved specificity of 9.7%, a loss of sensitivity of 4.4%, and an overall net reclassification index of 0.053. CONCLUSION: Based on the 2019 ESC guidelines, dual antithrombotic treatment should be considered in one-third of CCS patients. The CHADS-P2A2RC score improved risk classification and may particularly identify low-risk patients with limited benefit from treatment.

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.

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.

Cangrelor in combination with ticagrelor provides consistent and potent P2Y12-inhibition during and after primary percutaneous coronary intervention in real-world patients with ST-segment-elevation myocardial infarction.

Patients pretreated with ticagrelor with less than 1 hour from percutaneous coronary intervention (PCI) or receiving ticagrelor in cath lab were prospectively included and received cangrelor. Cangrelor was infused for 2 hours and platelet function was assessed as P2Y12 reactivity units (PRU) with the VerifyNow P2Y12 function assay before start of infusion, 15 min after the start of infusion, and 30 min after the end of infusion. A total of n = 32 patients with an average age of 68 (±13) years with n = 22 (69%) males were included. The level of P2Y12 inhibition before cangrelor infusion was started was 249 PRU (IQR 221-271). After 15 min of cangrelor infusion the P2Y12 reactivity was markedly decreased to 71 PRU (IQR 52-104, p < 0.001). At 30 min after end of infusion PRU remained within the therapeutic range, 89 PRU (IQR 50-178; p < 0.001 for comparison with preinfusion) with only n = 4 (12.5%) patients with PRU >225. Results were consistent between patients receiving ticagrelor prehospital or in the cath lab and no statistical differences in PRU were noted between the two groups in any of the three measurements. In conclusion, cangrelor in combination with ticagrelor results in consistent and strong P2Y12 inhibition during and after infusion and cangrelor may bridge the gap until oral P2Y12 inhibitors achieve effect in real-world STEMI patients undergoing primary PCI.

SGLT2 inhibitors for patients with type 2 diabetes mellitus after myocardial infarction: a nationwide observation registry study from SWEDEHEART.

Background: Sodium-glucose co-transporter 2 (SGLT2) inhibitors have been shown to reduce rates of heart failure hospitalisations and cardiovascular death in patients with type 2 diabetes and prior cardiovascular disease. We hypothesised that SGLT2 inhibitors could provide cardiovascular benefits in the post-myocardial infarction setting. We aimed to investigate cardiovascular outcomes of SGLT2 inhibitor therapy in patients with type 2 diabetes mellitus after myocardial infarction in a Swedish nationwide registry. Methods: We included all patients with type 2 diabetes surviving a type 1 acute myocardial infarction from January 1, 2018 to December 31, 2021. Patients were included if they were discharged with an estimated glomerular filtration rate (eGFR) > 30 mL/min/1.73 m2 in the nationwide Swedish Web-system for Enhancement and Development of Evidence-based care in Heart disease Evaluated According to Recommended Therapies (SWEDEHEART) registry. We identified all patients discharged with or without an SGLT2 inhibitor prescription 120 days before or within three days after discharge from the cardiac care unit. The primary outcome measure was a composite of death and first hospitalisation for heart failure after one year analysed using an adjusted Cox regression. Findings: A total of 11,271 patients were included. Of these, 2498 (22.2%) received SGLT2 inhibitor treatment. Patients who were prescribed SGLT2 inhibitors were younger, more often presented with a STEMI and had worse left ventricular ejection fraction at index hospitalisation. SGLT2 inhibitor use was associated with lower rates of the composite outcome (hazard ratio (HR) of 0.70 (95% confidence interval (CI) 0.59-0.82). Interpretation: Treatment with SGLT2 inhibitors after myocardial infarction in patients with type 2 diabetes was associated with a lower rate of cardiovascular events. Funding: This work was supported by Hjärt-Lungfonden, Vetenskapsrådet, Knut and Alice Wallenberg Foundation, ALF, the Bundy Academy, and Skåne University Hospital funds.

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.

Myocardial infarction in a population-based cohort of patients with biopsy-confirmed giant cell arteritis in southern Sweden.

OBJECTIVES: To determine the incidence rate (IR) of myocardial infarction (MI), relative risk of MI, and impact of incident MI on mortality in individuals with biopsy-confirmed giant cell arteritis (GCA). METHODS: MIs in individuals diagnosed with GCA 1998-2016 in Skåne, Sweden were identified by searching the SWEDEHEART register, a record of all patients receiving care for MI in a coronary care unit (CCU). The regional diagnosis database, with subsequent case review, identified GCA patients receiving care for MI outside of a CCU. A cohort of 10 reference subjects for each GCA case, matched for age, sex and area of residence, was used to calculate the incidence rate ratio (IRR) of MI in GCA to that in the general population. RESULTS: The GCA cohort comprised 1134 individuals. During 7958 person-years of follow-up, 102 were diagnosed with incident MI, yielding an IR of 12.8 per 1000 person-years (95% CI 10.3 to 15.3). The IR was highest in the 30 days following GCA diagnosis and declined thereafter. The IRR of MI in GCA to that of the background population was 1.29 (95% CI 1.05 to 1.59). Mortality was higher in GCA patients who experienced incident MI than in those without MI (HR 2.8; 95% CI 2.2 to 3.6). CONCLUSIONS: The highest incidence of MI occurs within the 30 days following diagnosis of GCA. Individuals with GCA have a moderately increased risk of MI compared with a reference population. Incident MI has a major impact on mortality in GCA.

Percutaneous coronary intervention plus medical therapy versus medical therapy alone in chronic coronary syndrome: a propensity score-matched analysis from the Swedish Coronary Angiography and Angioplasty Registry.

BACKGROUND: Percutaneous coronary intervention (PCI) is frequently used for patients with chronic coronary syndrome (CCS). However, the role of PCI beyond symptom relief in CCS remains controversial. The objective of this study was to determine whether PCI is associated with better outcomes, compared with medical therapy (MT) alone. METHODS: We conducted a retrospective cohort study. Using the Swedish Coronary Angiography and Angioplasty Registry, we included all patients with CCS undergoing coronary angiography in Sweden between 2010 and 2020. Two groups were formed based on treatment strategy: PCI+MT versus MT alone. One-to-one propensity score (PS) matching was used to address confounding. Outcome was assessed using matched win ratio analysis, a statistical method that ranks the components of the composite by clinical importance. The primary outcome was net adverse clinical event (NACE) within 5 years. In the win ratio analysis, the components of NACE were ranked as follows: (1) all-cause mortality, (2) myocardial infarction (MI), (3) bleeding and (4) urgent revascularisation. Secondary outcomes were the individual components of NACE, major adverse cardiovascular events (MACE) and cardiovascular mortality. RESULTS: After PS matching, two groups of 7220 patients each were formed. The hierarchical outcome analysis of NACE and MACE showed that PCI was associated with improved outcome (matched win ratio: 1.28 (95% CI 1.20 to 1.36, p<0.001) and matched win ratio: 1.38 (95% CI 1.29 to 1.48, p<0.001), respectively). The use of PCI was associated with higher win ratio of MI (matched win ratio: 1.15, 95% CI 1.04 to 1.28, p=0.008), urgent revascularisation (matched win ratio: 1.85, 95% CI 1.69 to 2.03, p<0.001) and cardiovascular mortality (matched win ratio: 1.15, 95% CI 1.00 to 1.34, p=0.044). No difference in win ratio was observed for all-cause mortality or bleeding. CONCLUSIONS: In this study, which sought to evaluate the outcomes of patients with CCS using a hierarchical approach, patients selected for revascularisation with PCI experienced better outcome compared with MT alone.

Abbreviated Versus Standard Dual Antiplatelet Therapy Times After Percutaneous Coronary Intervention in Patients With High Bleeding Risk With Acute Coronary Syndrome: Insights From the SWEDEHEART Registry.

BACKGROUND: Dual antiplatelet therapy (DAPT) reduces ischemic events but increases bleeding risk, especially in patients with high bleeding risk (HBR). This study aimed to compare outcomes of abbreviated versus standard DAPT strategies in patients with HBR with acute coronary syndrome undergoing percutaneous coronary intervention. METHODS AND RESULTS: Patients from the SWEDEHEART (Swedish Web-system for Enhancement and Development of Evidence-Based Bare in Heart Disease Evaluated According to Recommended Therapies) registry with at least 1 HBR criterion who underwent percutaneous coronary intervention for acute coronary syndrome were identified and included. Patients were divided into 2 groups based on their planned DAPT time at discharge: 12-month DAPT or an abbreviated DAPT strategy and matched according to their prescribed P2Y12 inhibitor at discharge. The primary outcome assessed was time to net adverse clinical events at 1 year, which encompassed cardiac death, myocardial infarction, ischemic stroke, or clinically significant bleeding. Time to major adverse cardiovascular events and the individual components of net adverse clinical events were considered secondary end points. A total of 4583 patients were included in each group. The most frequently met HBR criteria was age older than 75 years (65.6%) and Predicting Bleeding Complications in Patients Undergoing Stent Implantation and Subsequent Dual Antiplatelet Therapy score ≥25 (44.6%) in the standard DAPT group and oral anticoagulant therapy (79.6%) and age 75 years and older (55.2%) in the abbreviated DAPT group. There was no statistically significant difference in net adverse clinical events (12.9% versus 13.1%; hazard ratio [HR], 0.99 [95% CI, 0.88-1.11], P=0.83), major adverse cardiovascular events (8.6% versus 7.9%; HR, 1.08 [95% CI, 0.94-1.25]), or their components between groups. The results were consistent among all of the investigated subgroups. CONCLUSIONS: In patients with HBR undergoing percutaneous coronary intervention due to acute coronary syndrome, abbreviated DAPT was associated with comparable rates of net adverse clinical events and major adverse cardiovascular events to a DAPT duration of 12 months.

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.

Comparison between ticagrelor and clopidogrel in myocardial infarction patients with high bleeding risk.

AIMS: Ticagrelor is associated with a lower risk of ischemic events than clopidogrel. However, it is uncertain whether the benefits of more intensive anti-ischemic therapy outweigh the risks of major bleeding in patients who have a high bleeding risk (HBR). Therefore, this study compared ticagrelor and clopidogrel in myocardial infarction (MI) patients with HBR. METHODS AND RESULTS: This study included all patients enrolled in the SWEDEHEART registry who were discharged with dual antiplatelet therapy using ticagrelor or clopidogrel following MI between 2010 and 2017. High bleeding risk was defined as a PRECISE-DAPT score ≥25. Information on ischemic events, major bleeding, and mortality was obtained from national registries, with 365 days of follow-up. Additional outcomes include major adverse cardiovascular events (MACE), a composite of MI, stroke and all-cause mortality, and net adverse clinical events (NACE), a composite of MACE and bleeding. This study included 25 042 HBR patients, of whom 11 848 were treated with ticagrelor. Ticagrelor was associated with a lower risk of MI, stroke, and MACE, but a higher risk of bleeding compared to clopidogrel. There were no significant differences in mortality and NACE. Additionally, when examining the relationship between antiplatelet therapy and bleeding risk in 69 040 MI patients, we found no statistically significant interactions between the PRECISE-DAPT score and treatment effect. CONCLUSIONS: We observed no difference in NACE when comparing ticagrelor and clopidogrel in HBR patients. Moreover, we found no statistically significant interactions between bleeding risk and the comparative effectiveness of clopidogrel and ticagrelor in a larger population of MI patients.

Intracoronary Imaging of Proximal Coronary Artery Lesions - A Nationwide Lesion-Level Analysis From SCAAR.

Background: Current evidence suggests that use of intracoronary imaging during percutaneous coronary intervention (PCI) of the left main coronary artery (LMCA) reduces mortality. However, there is a scarcity of data on the overall role of intracoronary imaging, particularly in other non-LMCA proximal coronary artery lesions. We aimed to investigate the association of use of intracoronary imaging on outcome in proximal lesions treated with PCI. Methods: The Swedish Coronary Angiography and Angioplasty Registry was used to identify all proximal coronary artery lesions treated with stent implantation between June 11, 2013, and January 16, 2021. Proximal coronary artery lesions (LMCA, proximal left anterior descending artery, left circumflex artery, and right coronary artery) assessed by intracoronary imaging before and/or after stent implantation were matched to control lesions treated based on angiography alone using propensity score matching. The primary end point was target lesion revascularization with PCI, and secondary end points included all-cause mortality and definite stent thrombosis within 3 years. Results: Among the 3623 matched pairs, intracoronary imaging was associated with significantly lower risk of target lesion revascularization, 3.7% vs 4.7%; hazard ratio (HR), 0.77; 95% CI, 0.61-0.97; P = .025, and all-cause mortality, 9.1% vs 12.8%; HR, 0.70; 95% CI, 0.61-0.81; P < .001, with no difference in definite stent thrombosis. Conclusions: The use of intracoronary imaging in proximal coronary artery lesions is associated with lower rates of repeat revascularization and better survival. The results appear to be primarily driven by improved outcome of LMCA lesions. These results reinforce the role of intracoronary imaging in assessing and treating proximal coronary lesions.

Long-term Safety of Revascularization Deferral Based on Instantaneous Wave-Free Ratio or Fractional Flow Reserve.

Background: Deferral of coronary revascularization is safe whether guided by instantaneous wave-free ratio (iFR) or by fractional flow reserve (FFR). We aimed to assess long-term outcomes in patients deferred from revascularization based on iFR or FFR in a large real-world population. Methods: From 2013 through 2017, 201,933 coronary angiographies were registered in the Swedish Web-System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies (SWEDEHEART). We included all patients (n = 11,324) with at least 1 coronary lesion deferred from PCI during an index procedure using iFR (>0.89; n = 1998) or FFR (>0.80; n = 9326). The primary outcome was major adverse cardiac events (MACE) defined as the composite of all-cause death, nonfatal myocardial infarction, or unplanned revascularization. A multivariable-adjusted Cox proportional hazards model was used, with analysis for interaction of prespecified subgroups. Results: Patients presented with stable angina pectoris (iFR 46.9% vs FFR 48.6%), unstable angina or non-ST-elevation myocardial infarction (iFR 37.7% vs FFR 33.1%), ST-elevation myocardial infarction (iFR 1.9% vs FFR 1.6%), and other indications (iFR 12.5% vs FFR 15.7%). The median follow-up was 2 years for both iFR and FFR groups. At the conclusion of the study, the cumulative MACE risks were 26.7 for the iFR group and 25.9% for FFR group. In the adjusted analysis, no difference was found between the 2 groups (adjusted hazard ratio: iFR vs FFR, 0.947; 95% CI, 0.84-1.08; P = 39). Consistent with the overall findings, the prespecified subgroups showed no interaction with the FFR/iFR results. Conclusions: Deferral of revascularization showed similar long-term safety whether based on iFR or on FFR.

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.

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.

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.

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.

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.

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.