Events In ST-segment Elevation Myocardial Infarction Research Articles

Paramedic Ability in Interpreting Electrocardiogram with ST-segment Elevation Myocardial Infarction (STEMI) in Saudi Arabia.

ObjectiveTo evaluate paramedic ability in recognizing 12-lead Electrocardiogram (ECG) with ST-segment Elevation myocardial infarction (STEMI) in Saudi Arabia.MethodsThis is a quantitative exploratory cross-sectional study using an electronic survey of paramedics was conducted between June and September 2021. The survey included demographics, educational and clinical experiences, and multiple 12-lead ECG strip questions to assess participants’ ability to recognize STEMI. We reported the overall sensitivity, specificity, and correct proportions with 95% Confidence Intervals (CI).ResultsEighty-four paramedics completed the survey, and 65% of them were between 24 and 29 years old, with a median, of three years of field experience. Overall sensitivity and specificity were 58.39% (95% CI, 50.4% to 66.1%) and 29.01% (95% CI, 25.15% to 33.1%), respectively. In total, 67.1% correctly identified inferior STEMI, whereas only 50% correctly identified lateral STEMI. Both STEMIs were correctly identified by 41%, and the majority misinterpreted STEMI mimics (ECG rhythms with similar ECG morphology to STEMI). The proportion who correctly recognized left bundle branch block was 14.8%, pericarditis was 10.9%, and ventricular pacing was 1.4%. However, almost third of participants correctly identified right bundle branch block (32.9%) and left ventricle hypertrophy (30.7%). Overall, there was no correlation between the correct ECG interpretation of STEMIs and educational and clinical experiences.ConclusionParamedics were able to identify STEMI events in prehospital settings with moderate sensitivity and low specificity with limited ability to differentiate between STEMI and STEMI mimics. Therefore, additional training in ECG interpretation could improve their clinical decision-making, and to ensure that proper care and treatment is provided. Further research on a large, representative sample of paramedics across the country could provide more definitive evidence to establish a greater degree of accuracy in detecting STEMI in prehospital settings.

Short-term exposure to traffic-related air pollution and STEMI events: Insights into STEMI onset and related cardiac impairment

AimsEvidence on the impacts of traffic-related air pollution (TRAP) on ST-segment elevation myocardial infarction (STEMI) events is limited. We aimed to assess the acute effects of TRAP exposure on the clinical onset of STEMI and related cardiac impairments. Methods and resultsWe recruited patients who were admitted for STEMI and underwent primary percutaneous coronary intervention at Peking University Third Hospital between 2014 and 2020. Indicators relevant to cardiac impairments were measured. Concomitantly, hourly concentrations of traffic pollutants were monitored throughout the study period, including fine particulate matter, black carbon (BC), particles in size ranges of 5–560 nm, oxides of nitrogen (NOX), nitrogen dioxide, and carbon monoxide. The mean (SD) age of participants was 62.4 (12.5) years. Daily average (range) concentrations of ambient BC and NOX were 3.9 (0.1–25.0) μg/m3 and 90.8 (16.6–371.7) μg/m3. Significant increases in STEMI risks of 5.9% (95% CI: 0.1, 12.0) to 21.9% (95% CI: 6.0, 40.2) were associated with interquartile range increases in exposure to TRAP within a few hours. These changes were accompanied by significant elevations in cardiac troponin T levels of 6.9% (95% CI: 0.2, 14.1) to 41.7% (95% CI: 21.2, 65.6), as well as reductions in left ventricular ejection fraction of 1.5% (95% CI: 0.1, 2.9) to 3.7% (95% CI: 0.8, 6.4). Furthermore, the associations were attenuated in participants living in areas with higher residential greenness levels. ConclusionsOur findings extend current understanding that short-term exposure to higher levels of traffic pollution was associated with increased STEMI risks and exacerbated cardiac impairments, and provide evidence on traffic pollution control priority for protecting vulnerable populations who are at greater risks of cardiovascular events.

Factors associated with prehospital delay in patients with ST-segment elevation myocardial infarction.

Longer ischemia time is known to be related to adverse outcomes in patients with acute ST-segment elevation myocardial infarction (STEMI). Delay in time from symptom onset to emergency department (ED) has been studied less. The aim of this study was to define the clinical, transportation and residential factors associated with longer pre-hospital delay in STEMI events. Total 308 successive patients presenting to Poriya Medical Center with STEMI between Feb 2015 and Dec 2017 were retrospectively identified. The final cohort included 266 patients after excluding inpatient STEMI, files missing time of pain onset and patients in cardiac arrest. Clinical and transport data were retrieved from the cardiology department database. Our primary clinical outcome was 1-year all-cause mortality. Univariable and multivariable logistic regression analyses were performed to define factors associated with prehospital delay. In the total cohort, the patients' mean age was 61 ± 11 years old, 81% were male, and patients lived 21 ± 12 km from our medical center. On multivariable logistic regression analysis, a stop at the community clinic and diabetes were associated with increased risk of a delay. Longer delays were associated with reduced ejection fraction at discharge, higher rates of readmissions and higher all-cause 1-year mortality. The strongest determinant of prehospital delay in STEMI events was seeking first medical care at a community clinic, which was associated with the worst outcomes. This highlights the importance of education of both patients and primary clinic staff regarding the identification and prioritization of STEMI patients and immediate evacuation by emergency medical service.

Short-Term Effects of Ambient Air Pollution on ST-Elevation Myocardial Infarction Events: Are There Potentially Susceptible Groups?

Background: Air pollution exposure is associated with greater risk for cardiovascular events. This study aims to examine the effects of increased exposure to short-term air pollutants on ST-segment elevation myocardial infarction (STEMI) and determine the susceptible groups. Methods: Data on particulate matter PM2.5 and PM10 and other air pollutants, measured at each of the 11 air-quality monitoring stations in Kaohsiung City, were collected between 2011 and 2016. The medical records of non-trauma adult (>17 years) patients who had visited the emergency department (ED) with a typical electrocardiogram change of STEMI were extracted. A time-stratified and case-crossover study design was used to examine the relationship between air pollutants and daily ED visits for STEMI. Results: An interquartile range increment in PM2.5 on lag 0 was associated with an increment of 25.5% (95% confidence interval, 2.6%–53.4%) in the risk of STEMI ED visits. Men and persons with ≥3 risk factors (male sex, age, hypertension, diabetes, current smoker, dyslipidemia, history of myocardial infarction, and high body mass index) for myocardial infarction (MI) were more sensitive to the hazardous effects of PM2.5 (interaction: p = 0.039 and p = 0.018, respectively). The associations between PM10, NO2, and O3 and STEMI did not achieve statistical significance. Conclusion: PM2.5 may play an important role in STEMI events on the day of exposure in Kaohsiung. Men and persons with ≥3 risk factors of MI are more susceptible to the adverse effects of PM2.5 on STEMI.

Role of Soluble ST2 Levels and Beta-Blockers Dosage on Cardiovascular Events of Patients with Unselected ST-Segment Elevation Myocardial Infarction.

Background:Serum soluble ST2 (sST2) levels are elevated early after acute myocardial infarction and are related to adverse left ventricular (LV) remodeling and cardiovascular outcomes in ST-segment elevation myocardial infarction (STEMI). Beta-blockers (BB) have been shown to improve LV remodeling and survival. However, the relationship between sST2, final therapeutic BB dose, and cardiovascular outcomes in STEMI patients remains unknown.Methods:A total of 186 STEMI patients were enrolled at the Wuhan Asia Heart Hospital between January 2015 and June 2015. All patients received standard treatment and were followed up for 1 year. Serum sST2 was measured at baseline. Patients were divided into four groups according to their baseline sST2 values (high >56 ng/ml vs. low ≤56 ng/ml) and final therapeutic BB dose (high ≥47.5 mg/d vs. low <47.5 mg/d). Cox regression analyses were performed to determine whether sST2 and BB were independent risk factors for cardiovascular events in STEMI.Results:Baseline sST2 levels were positively correlated with heart rate (r = 0.327, P = 0.002), Killip class (r = 0.408, P = 0.000), lg N-terminal prohormone B-type natriuretic peptide (r = 0.467, P = 0.000), lg troponin I (r = 0.331, P = 0.000), and lg C-reactive protein (r = 0.307, P = 0.000) and negatively correlated to systolic blood pressure (r = −0.243, P = 0.009) and LV ejection fraction (r = −0.402, P = 0.000). Patients with higher baseline sST2 concentrations who were not titrated to high-dose BB therapy (P < 0.0001) had worse outcomes. Baseline high sST2 (hazard ratio [HR]: 2.653; 95% confidence interval [CI]: 1.201–8.929; P = 0.041) and final low BB dosage (HR: 1.904; 95% CI, 1.084–3.053; P = 0.035) were independent predictors of cardiovascular events in STEMI.Conclusions:High baseline sST2 levels and final low BB dosage predicted cardiovascular events in STEMI. Hence, sST2 may be a useful biomarker in cardiac pathophysiology.

Prognostic Value of New-Generation Troponins in ST-Segment-Elevation Myocardial Infarction in the Modern Era: The RUTI-STEMI Study.

BackgroundIn ST‐segment–elevation myocardial infarction (STEMI), troponins are not needed for diagnosis: symptoms and ECG data are sufficient to activate percutaneous coronary intervention. This study explored the prognostic value of new‐generation troponins in a real‐life cohort contemporarily treated for STEMI.Methods and ResultsWe studied 1260 consecutive patients with primary STEMI treated with percutaneous coronary intervention between February 22, 2011, and August 31, 2015. We collected data on clinical characteristics and major adverse cardiovascular and cerebrovascular events (MACCEs) at 30 days and 1 year. Peak high‐sensitivity troponin T and sensitive‐contemporary troponin I levels were recorded. MACCEs occurred in 75 patients (6.1%) by day 30 and in 124 patients (10.8%) between day 31 and 1 year. A short‐term (0–30 days) multivariable Cox regression analysis revealed that age, Killip‐Kimball class, and left ventricular ejection fraction were independent predictors of MACCEs. In adjusted analysis, peak high‐sensitivity troponin T and sensitive‐contemporary troponin I were not significant (hazard ratio, 1.23 [95% confidence interval, 0.98–1.54] [P=0.071]; and hazard ratio, 1.15 [95% confidence interval, 0.93–1.43] [P=0.200], respectively). A long‐term (31 days–1 year) multivariable Cox regression analysis revealed that age, female sex, diabetes mellitus, prior coronary artery disease, Killip‐Kimball class, and left ventricular ejection fraction were statistically significantly associated with MACCEs. However, peak high‐sensitivity troponin T and peak sensitive‐contemporary troponin I were not significantly associated with MACCEs (hazard ratio, 1.03 [95% confidence interval, 0.88–1.20] [P=0.715]; and hazard ratio, 0.99 [95% confidence interval, 0.85–1.15] [P=0.856], respectively).ConclusionsIn the modern era, new‐generation troponins do not provide significant prognostic information for predicting clinical events in STEMI. We should reconsider the value of serial troponin measurements for risk stratification in STEMI.

Assessment of coronary care management and hospital mortality from ST-segment elevation myocardial infarction in the Kazakhstan population: Data from 2012 to 2015

ObjectiveThe aim of this study was to assess and evaluate factors related to coronary care management and hospital mortality in patients with ST-segment elevation myocardial infarction (STEMI) hospitalized in the Kazakhstan County and city hospitals in which percutaneous coronary intervention (PCI) was performed during the period of 2012–2015. Materials and methodsA total of 22,176 adult patients (18> years) with acute STEMI were hospitalized from January 2012 to December 2015. All the investigated STEMI patients underwent PCI. ResultsThe mean age of STEMI patients was 61.52±11.48 years, 72.2% of the patients were male and 75.2% living in the rural regions. The mean time from hospitalization to PCI was 2104.41±5060.68min (median 95.0 and IQR 1034.5). The mean and median of time from hospitalization to PCI tended to decrease from 2747.7±5793.9min and 155.0min in 2012 to 1874.7±4759.2min and 73.5min in 2015. Among all STEMI events the percentage of patients from hospitalization to PCI within 0–59min was up to 39.0% during all study period. From 2012 to 2015, the percentage of STEMI patients with short time (0–59min) of hospitalization to PCI tended to increase in average by 11.4% per year (P=0.09). Among all STEMI patients hospital mortality from 2012 to 2015 did not change significantly and ranged from 9.0% in 2012 to 8.6% in 2015. By multiple logistic regression analysis, study years (2012), gender (female), age (60> years), time from hospitalization to PCI (60>min) and number of bed-days were statistically significant factors associated with patients’ hospital mortality from STEMI with PCI. ConclusionsThe present study demonstrated that hospitalization delay in the treatment of STEMI patients in Kazakhstan population was without significant changes, meanwhile the number of patients perfused within 1h from hospitalization to PCI tended to increase during 2012–2015. The higher hospital mortality was associated with study year, female gender, older age, longer-time from hospitalization to PCI and shorter hospitalization.

Abstract 4910: Integrated Approach By Using Coronary Flow Velocity Reserve And Coronary Flow Velocity Patterns In Predicting Long-term Adverse Cardiac Events In Acute Myocardial Infarction

Background: The microvascular function was known to be an useful predictor of left ventricular functional changes and clinical outcomes in ST-segment elevation myocardial infarction (STEMI). We evaluated the usefulness of integrated approach by using coronary flow velocity reserve (CFR) and diastolic deceleration time (DDT) in the prediction of long-term major adverse cardiac events in STEMI. Methods and Results: Using an intracoronary Doppler wire, CFR, DDT and hyperemic microvascular resistance index (MVRI) were evaluated in 202 patients with first STEMI received reperfusion therapy within 24 hours after onset of symptoms. Major adverse cardiac events were the composite of cardiac death, recurrent myocardial infarction, congestive heart failure and stroke during an average follow-up period of 60 ± 39 months. Follow-up echocardiography was performed at 12 ± 9 months. CFR, DDT and MVRI had significant correlations with left ventricular regional wall motion score index at follow-up echocardiography (r =−0.441, p&lt;0.001; r = 0.413, p&lt;0.001; r =−0.485, p&lt;0.001, respectively). Using receiver-operating characteristics analysis, CFR ≤1.3 (sensitivity: 51%, specificity: 78%), DDT ≤577 ms (sensitivity: 72%, specificity: 62%) and MVRI &gt;2.7 (sensitivity: 68%, specificity: 67%) were the best cutoff values in the prediction of occurring the adverse cardiac events. In patients with CFR ≤1.3, DDT ≤577 ms, cardiac events were occurred in 18 patients (40.0 %) of 45 patients, whereas cardiac events were occurred in 12 patients (20.3%) of 59 patients with CFR &gt;1.3 and DDT ≤577 ms or CFR ≤1.3 and DDT &gt;577 ms (p= 0.048), 9 patients (9.1%) of 99 patients with CFR&gt;1.3 and DDT &gt;577 ms (p&lt;0.001). Ejection fraction at admission (p=0.009), MVRI (p =0.002) and DDT (p=0.023) were independent predictors in the prediction of long-term adverse cardiac outcomes during follow-up. Conclusions: Integrated approach by using CFR and DDT was useful in the prediction of long-term adverse cardiac events. MVRI and DDT were strong independent predictors of long-term adverse cardiac events in STEMI patients.

The challenge of ST-segment elevation myocardial infarction

Acute coronary syndromes (ACS) represent a spectrum of ischaemic myocardial events that share a similar pathophysiology. ST-segment elevation myocardial infarction (STEMI), the most severe form of ACS short of sudden cardiac death, is a significant public health problem with an estimated 500,000 STEMI events every year in the United States. The mortality and morbidity associated with STEMI is significant. Early reperfusion therapy is the most important aspect of the treatment of STEMI. There are two main methods of reperfusion therapy: percutaneous coronary intervention (PCI) and fibrinolytic therapy, with PCI being the preferred method. In addition to standard reperfusion therapy, antithrombotics (unfractionated heparin and low molecular weight heparins) and antiplatelet agents (aspirin, clopidogrel and glycoprotein IIb/IIIa inhibitors) are critical adjuncts, effective in the treatment of acute STEMI. The survival of patients with STEMI depends on rapid diagnosis and optimal early treatment. Guidelines for the management of patients with STEMI recommend PCI within 90 min of presentation and that fibrinolytics are administered within 30 min. However, only a fraction of patients undergo reperfusion within the recommended time. Improvements in protocols for identifying STEMI cases are therefore required to allow reperfusion therapy to be initiated sooner. Secondary prevention is another important aspect of STEMI management, and patients should be encouraged to adopt strategies that reduce the risk of subsequent ischaemic events.

Potential generation of geographical inequities by the introduction of primary percutaneous coronary intervention for the management of ST segment elevation myocardial infarction

BackgroundPrimary Percutaneous Coronary Intervention (PCI) is more efficacious than thrombolysis in the management of acute myocardial infarction, but, because of the requirement for prompt treatment, there are practical challenges in developing such services. We examined the proportion of patients with ST segment Elevation Myocardial Infarction (STEMI) who could receive timely treatment from a primary Percutaneous Coronary Intervention (PCI) service assuming different geographical locations of potential treatment centres in three English counties.Methods and resultsInformation on the residential location of patients with new STEMI hospitalisations recorded in Hospital Episodes Statistics was analysed and the proportion of episodes of STEMI within 60' and 45' travel time isochrones from potential primary PCI centres in three English counties was calculated. There were on average 1,815 new STEMI hospitalisations per year occurring in the studied population. Introduction of a primary PCI service in one, two or three potential treatment centres would have covered respectively 28%, 73% and 90% of such episodes within 60 minutes travel time, and 17%, 51% and 69% within 45 minutes travel time.ConclusionIn the study context, a primary PCI service in an existing tertiary centre would only cover a minority of STEMI events and would generate geographical inequities. A two-centre model would improve coverage and equity considerably, but may be associated with practical, clinical quality and financial challenges.

Simple Principles of Clinical Trials Remain Powerful

IN THIS ISSUE OF JAMA, 2 ARTICLES FROM THE CLINICAL Trial of Reviparin and Metabolic Modulation in Acute Myocardial Infarction Treatment Evaluation (CREATE) greatly enhance the knowledge base for the treatment of acute ST-segment elevation myocardial infarction (STEMI). Yet, as with all good clinical trials, this study raises new questions and perspectives that deserve further consideration. The factorial design of the CREATE trial proves 2 points: (1) low-molecular-weight heparin reduces mortality and ischemic events in STEMI and (2) the age-old argument about glucose, insulin, and potassium (GIK) therapy can be put to rest—this treatment does not work in STEMI. The CREATE trial is powerful and definitive on both counts. However, the conduct and results of the trial stimulate thoughts about several questions. Do the Principles of Pragmatic Clinical Trials Still Hold in This Era of “Personalized Medicine”? Despite ongoing efforts to develop more targeted approaches to therapeutics using biomarkers and genomics, the majority of therapies for complex diseases act through mechanisms that are not specifically targeted. Accordingly, a trial of adequate size to show modest but important effects on true clinical outcomes must remain the standard for the evidence on which therapies are based. In fact, it is easy to postulate many mechanistic reasons why either of the therapies tested in CREATE would or would not “work,” but the definitive proof requires an accounting of the risks and benefits using the “big 4” measures: length of life, quality of life, discrete negative events, and costs. The CREATE investigators used a technique that is all too often avoided: a factorial design. In essence, this approach allows 2 questions to be simultaneously answered for little more than the effort of 1. The most common reason for eschewing factorial designs is the fear that in a regulatory setting the adverse effects of one drug (or device) will be attributed to the other being tested. The timidity of sponsors and investigators to embrace factorial designs must be overcome if researchers are to answer the multitude of critical questions about old and new therapies, especially the interactions among them. Given the increasing evidence that the drug and device research and development system is not producing the evidence that is needed to guide practice, regulators would be well served to encourage factorialdesign studies. Even more important, the CREATE trial eliminated useless, redundant approaches to clinical trial management, permitting a clear answer to 2 important questions for the global community of patients with myocardial infarction. Data forms were brief, redundant monitoring visits were not done, and adverse event reporting was limited to critical issues. By making the trial less burdensome on the investigators, the CREATE investigators encouraged and accomplished broad participation without need for external funding. Today’s overly complex “regulatory trials” tend to lead to dataintensive studies with inadequate numbers of patients and end points that do not measure length or quality of life. More trials like CREATE are needed, with fewer of these “regulatory” trials. What Does This Trial Show About GIK Infusion? This “generic” therapy has survived decades of clinical practice without a definitive test of its safety and effectiveness. The conceptual basis for its use is sound, and its rationale has been delineated in a variety of publications cited by the CREATE investigators. Unfortunately, regardless of its scientific rationale and the positive results of small studies, this definitive trial, combined with a previous overview that showed only a modest potential benefit, answers the question beyond reasonable doubt: there is no benefit of GIK therapy. Societal resources would be better spent on evaluating other approaches in clinical trials and using other therapies in practice. What Does This Trial Show About Reviparin? Antithrombotic therapy has become a mainstay of treatment of acute coronary syndromes (ACS), but the accrual of definitive evidence has been hampered by the fact that unfractionated heparin (UFH) became standard before the era of definitive clinical outcome trials. Thus, the CREATE investigators are technically correct in their attack on UFH in the discussion section of their article. However, directly com-