Predicting Acute Cardiovascular Complications in COVID-19: Insights from a Specialized Cardiac Referral Department.

BACKGROUND COVID-19 increases the risk of acute cardiovascular diseases (CVDs), including acute coronary syndrome (ACS), acute pulmonary embolism (APE), and acute myocarditis (AMyo). The actual impact of CVDs on mortality of patients with COVID-19 remains unknown. This study aimed to determine whether CVDs influence the course of COVID-19 pneumonia and if they can be easily detected by using common tests and examinations. MATERIAL AND METHODS Data of 249 consecutive patients with COVID-19 hospitalized in a dedicated cardiology department were analyzed. On admission, clinical status, biomarkers, computed tomography, and bedside echocardiography were performed. RESULTS D-dimer level predicted APE (AUC=0.850 95% CI [0.765; 0.935], P<0.001) with sensitivity of 69.4% and specificity of 96.2% for a level of 4968.0 ng/mL, and NT-proBNP predicted AMyo (AUC=0.692 95% CI [0.502; 0.883], P=0.004) and showed sensitivity of 54.5%, with specificity of 86.5% for the cut-off point of 8970 pg/mL. Troponin T levels were not useful for diagnostic differentiation between CVDs. An extent of lung involvement predicted mortality (OR=1.03 95% CI [1.01;1.04] for 1% increase, P<0.001). After adjusting for lung involvement, ACS increased mortality, compared with COVID-19 pneumonia only (OR=5.27 95% CI [1.76; 16.38] P=0.003), while APE and AMyo did not affect risk for death. CONCLUSIONS D-dimer and NT-proBNP, but not troponin T, are useful in differentiating CVDs in patients with COVID-19. ACS with COVID-19 increased in-hospital mortality independently from extent of lung involvement, while coexisting APE or AMyo did not.

Effects of the stress hyperglycemia ratio on long-term mortality in patients with triple-vessel disease and acute coronary syndrome.

AIMS: Risk assessment for triple-vessel disease (TVD) remain challenging. Stress hyperglycemia represents the regulation of glucose metabolism in response to stress, and stress hyperglycemia ratio (SHR) is recently found to reflect true acute hyperglycemic status. This study aimed to evaluate the prognostic value of SHR and its role in risk stratification in TVD patients with acute coronary syndrome (ACS). METHODS: A total of 3812 TVD patients with ACS with available baseline SHR measurement were enrolled from two independent centers. The endpoint was cardiovascular mortality. Cox regression was used to evaluate the association between SHR and cardiovascular mortality. The SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) II (SSII) was used as the reference model in the model improvement analysis. RESULTS: During a median follow-up of 5.1 years, 219 (5.8%) TVD patients with ACS suffered cardiovascular mortality. TVD patients with ACS with high SHR had an increased risk of cardiovascular mortality after robust adjustment for confounding (high vs. median SHR: adjusted hazard ratio 1.809, 95% confidence interval 1.160-2.822, P = 0.009), which was fitted as a J-shaped pattern. The prognostic value of the SHR was found exclusively among patients with diabetes instead of those without diabetes. Moreover, addition of SHR improved the reclassification abilities of the SSII model for predicting cardiovascular mortality in TVD patients with ACS. CONCLUSIONS: The high level of SHR is associated with the long-term risk of cardiovascular mortality in TVD patients with ACS, and is confirmed to have incremental prediction value beyond standard SSII. Assessment of SHR may help to improve the risk stratification strategy in TVD patients who are under acute stress.

[Diagnosis of acute coronary syndrome]. / Diagnose des akuten Koronarsyndroms.

Acute coronary syndrome is one of the most important differential diagnostic considerations in emergency medicine. It describes the constellation of newly occurring clinical symptoms, often accompanied by typical 12-lead ECG changes and the release of cardiac troponins. The spectrum includes unstable angina pectoris, non-ST-segment elevation myocardial infarction (NSTEMI), and ST-segment elevation myocardial infarction (STEMI). It is important to consistently carry out the diagnostic steps that are crucial for further therapeutic procedures to avoid delaying life-saving invasive coronary diagnostics, without losing sight of the diverse, sometimes time-critical differential diagnoses. Anamnesis and clinical examination form the basis of the further procedure. Further developments of biomarker assays with personalized limit values, new imaging modalities with ever higher resolution and faster imaging methods as well as advances in automated ECG analysis with integration of all findings through artificial intelligence will continue to offer many optimization options in the future diagnosis of acute coronary syndrome.

[Treatment of Acute Coronary Syndromes]. / Therapie des akuten Koronarsyndroms.

Despite significant advances in the detection and rapid management of acute coronary syndromes (ACS), it continues to lead the cause of death statistics and they continuously represent the leading cause of death and living with disabilities, globally. Since ACS combine a spectrum of different diagnoses, a high degree of variability in possible clinical presentation and relevant gender differences, Individualised treatment is not always easy and is constantly changing due to novel evidence from research studies. Therefore, the aim of this article is therefore to explain relevant treatment options and to present the current state of science in the context of clinical patient treatment.

The effect of coronary stent policies on the risk of percutaneous coronary intervention among acute coronary syndrome patients in Shanghai: Real-world evidence.

OBJECTIVE: This study aimed to analyze the effect of coronary stent policies implemented in Shanghai on the risk of percutaneous coronary intervention (PCI) in acute coronary syndrome (ACS) inpatients based on real-world data. METHODS: Two retrospective cohorts of inpatients with a first diagnosis of ACS who had undergone PCI for the first time in the previous year in Shanghai hospitals were examined (one for the postpolicy period and the other for the prepolicy period). χ2 tests were used to compare categorical variables between the two cohorts. Single- and multivariate Cox proportional hazards models were used to compare the risk of major adverse cardiovascular events (MACEs) between the two cohorts. RESULTS: A total of 31,760 ACS patients were included in this study. The proportion of ACS inpatients who had at least one bid-winning stent and 3 or more coronary stents implanted for first-time PCI in the postpolicy cohort was higher than that in the prepolicy cohort (86.52% vs. 55.67% and 6.27% vs. 4.39%, respectively; all p values < 0.0001). The single- and multivariate Cox proportional hazards models revealed that the unadjusted and adjusted hazard ratios for MACEs at 1 year after PCI for the postpolicy cohort relative to the prepolicy cohort were 0.869 (P<0.0001) and 0.814 (P = 0.0007), respectively. CONCLUSIONS: The implementation of coronary stent policies changed coronary stent utilization but had no significant adverse effects on the risk of PCI among ACS patients in Shanghai in the short term. However, the reasons for changes in the number of coronary stents implanted should be analyzed and addressed in the future.

Prediabetes and major adverse cardiac events after acute coronary syndrome: An overestimated concept.

BACKGROUND: Unlike diabetes, the effect of prediabetes on outcomes in patients with acute coronary syndrome (ACS) who underwent percutaneous coronary intervention (PCI) is not much investigated. We investigated the association between fasting glycemic status and major adverse cardiovascular and cerebrovascular events (MACCE) in patients with ACS undergoing PCI and had mid to long-term follow-up after coronary stenting. METHODS: Registry-based retrospective cohort study included ACS patients who underwent PCI at the Tehran Heart Center from 2015 to 2021 with a median follow-up of 378 days. Patients were allocated into normoglycemic, prediabetic, and diabetic groups. The primary and secondary outcomes were MACCE and its components, respectively. Unadjusted and adjusted Cox models were used to evaluate the association between glycemic status and outcomes. RESULTS: Among 13 682 patients, 3151 (23%) were prediabetic, and 5834 (42.6%) were diabetic. MACCE risk was significantly higher for diabetic versus normoglycemic (adjusted hazard ratio [aHR]: 1.22, 95% confidence interval [CI]: 1.06-1.41), but nonsignificantly higher for prediabetic versus normoglycemic (aHR: 0.95, 95% CI: 0.78-1.10). All-cause mortality risk was significantly higher in diabetic versus normoglycemic (aHR: 1.42, 95% CI: 1.08-1.86), but nonsignificantly higher for prediabetic versus normoglycemic (aHR: 1.15, 95% CI: 0.84-1.59). Among other components of MACCE, only coronary artery bypass grafting was significantly higher in diabetic patients, and not prediabetic, compared with normoglycemic. CONCLUSIONS: Prediabetic ACS patients undergoing PCI, unlike diabetics, are not at increased risk of MACCE and all-cause mortality. While prediabetic patients could be regarded as having the same risk as nondiabetics, careful consideration to provide more intensive pre- and post-PCI care in diabetic patients is mandatory.

Characteristics of Patients With Acute Coronary Syndrome and Normal Electrocardiogram.

Background: Patients with acute coronary syndrome (ACS) and normal electrocardiogram (ECG) may have an increased risk of late diagnosis and complications of the disease. Objective: To study the demographic, angiographic and echocardiographic characteristics of patients hospitalized for ACS in whom the ECG was normal on admission to the hospital. Methods: This retrospective study included patients who were hospitalized for ACS without ST-elevation between 2015 and 2023 and who had coronary artery disease (CAD) confirmed by coronary angiography. By further inspection of the electronic databases, patients with ACS who had a normal ECG on admission were filtered out and analyzed separately. Results: Of the total 3137 patients with suspected ACS without ST-elevation, 129 patients (4.1%) were diagnosed as having ACS with a normal ECG. In three patients a non-atherosclerotic cause for the ACS was found. A significantly higher proportion of patients had single-vessel (54.3%) compared to two-vessel (29.5%) and three-vessel (14%) CAD. In addition to a normal ECG, 5.7% of patients with single-vessel CAD and 3.5% of patients with multi-vessel CAD had normal troponin levels and normal regional LV systolic function on echocardiography. Conclusion: Less than 5% of hospitalized patients with ACS without ST-elevation had a normal ECG on admission. The majority of these patients have single-vessel CAD. In about 5% of patients with single-vessel CAD, neither elevated troponin levels nor LV asynergy are detected.

Acute coronary syndrome patterns in the Young: risk factor profile and in-hospital outcomes in a tertiary referral hospital in Kenya.

INTRODUCTION: Acute coronary syndrome (ACS) accounts for coronary artery disease (CAD) -related morbidity and mortality. There has been growing concern about the rising incidence of ACS among young individuals globally both in developed and developing countries, including Sub-Saharan Africa. This group's phenotypic characteristics; risk factors and clinical outcomes are not well described. contextual and regional studies are necessary to understand the magnitude of ACS among young Individuals and help highlight challenges and opportunities for improved ACS outcomes in the region. The study aimed to describe the demographic and clinical characteristics of young individuals hospitalized with ACS and report on in-hospital outcomes. METHODOLOGY: This single-center retrospective study was conducted at the Aga Khan University Hospital, Nairobi. Medical records of all young individuals hospitalized with ACS from 30th June 2020 to 1st May 2023 were reviewed. We defined young individuals as 50 years or below. Categorical variables were reported as frequencies and proportions, and compared with Pearson chi- square or Fisher's exact tests. Continuous variables were reported as means or medians and compared with independent t-tests or Mann-Whitney U tests. P- value < 0.05 was considered statistically significant. RESULTS: Among 506 patients hospitalized with ACS, (n = 138,27.2%) were aged 50 years and below. The study population was male (n = 107, 79.9%) and African(n = 82,61.2%) predominant with a median age of 46.5 years (IQR 41.0-50.0). Hypertension (n = 101,75.4%) was noted in most study participants. More than half of the cohort were smokers (n = 69,51.5%) having a family history of premature ASCVD(n = 70,52.2%) and were on lipid-lowering therapy(n = 68,50.7%) prior to presentation. ST-segment-elevation myocardial infarction (STEMI) was the most common clinical manifestation of ACS (n = 77, 57.5%). Of the significant coronary artery disease (n = 75,56.0%), the majority of the individuals had single vessel disease (n = 60, 80%) with a predilection of left anterior deciding artery(n = 47,62.6%). The Main cause of ACS was atherosclerosis (n = 41,54.6%). The mean left ventricular ejection fraction was 46.0 (± 12.4). The in-hospital mortality was (n = 2, 1.5%). CONCLUSION: This study highlights that young individuals contribute to a relatively large proportion of patients presenting with ACS at our center. The most common presentation was STEMI. The principal cause was atherosclerosis. The findings of this study highlight the importance of developing systems of care that enable the early detection of CAD. Traditional cardiovascular risk factors were prevalent and modifiable, thus targets of intervention.

Superoxide dismutases: marker in predicting reduced left ventricular ejection fraction in patients with type 2 diabetes and acute coronary syndrome.

AIM: To examine the prognostic value of superoxide dismutase (SOD) activity for monitoring reduced left ventricular ejection fraction(LVEF)in the patients with type 2 diabetes and acute coronary syndrome (ACS). METHODS: The population of this cross-sectional study included 2377 inpatients with type 2 diabetes who had an ACS admitted to the Shandong Provincial Hospital Affiliated to Shandong First Medical University from January 2016 to January 2021. RESULTS: Diabetic patients with ACS were divided into 2 subgroups based on LVEF. The mean SOD activity was significantly lower in patients with an LVEF ≤ 45% than in those with an LVEF > 45% (149.1 (146.4, 151.9) versus 161.9 (160.8, 163.0)). Using ROC statistic, a cut-off value of 148.8 U/ml indicated an LVEF ≤ 45% with a sensitivity of 51.6% and a specificity of 73.7%. SODs activity were found to be correlated with the levels of NT-proBNP, hs-cTnT, the inflammatory marker CRP and fibrinogen. Despite taking the lowest quartile as a reference (OR 0.368, 95% CI 0.493-0.825, P = 0.001) or examining 1 normalized unit increase (OR 0.651, 95% CI 0.482-0.880, P = 0.005), SOD activity was found to be a stronger predictor of reduced LVEF than CRP and fibrinogen, independent of confounding factors. CONCLUSIONS: Our cross-sectional study suggests that SOD activity might be a valuable and easily accessible tool for assessing and monitoring reduced LVEF in the diabetic patients with ACS.

Retrospective review of non-ST segment elevation acute coronary syndrome presenting to the emergency department of a major tertiary center in Saudi Arabia.

BACKGROUND: Acute coronary syndrome (ACS) comprises a spectrum of diseases ranging from unstable angina (UA), non-ST elevation myocardial infarction (non-STEMI) and ST elevation myocardial infarction (STEMI). Treatment of ACS without STEMI (NSTEMI-ACS) can vary, depending on the severity of presentation and multiple other factors. OBJECTIVE: Analyze the NSTEMI-ACS patients in our institution. DESIGN: Retrospective observational. SETTING: A tertiary care institution with accredited chest pain center. PATIENTS AND METHODS: The travel time from ED booking to the final disposition for patients presenting with chest pain was retrieved over a period of 6 months. The duration of each phase of management was measured with a view to identify the factors that influence their management and time from the ED to their final destination. The data was analyzed using descriptive statistics. MAIN OUTCOME MEASURES: Travel time from ED to final destination. SAMPLE SIZE: 300 patients. RESULTS: The majority of patients were males (64%) between 61 and 80 years of age (45%). The median disposition time (from ED booking to admission order by the cardiology team) was 5 hours and 19 minutes. Cardiology admissions took 10 hours and 20 minutes from ED booking to the inpatient bed. UA was diagnosed in 153 (51%) patients and non-STEMI in 52 (17%). Coronary catheterization was required in 79 (26%) patients, 24 (8%) had coronary artery bypass grafting (CABG) and 8 (3%) had both catheterization and CABG. CONCLUSION: The time from ED booking to final destination for NSTEMI-ACS patients is delayed due to multiple factors, which caused significant delays in overall management. Additional interventional steps can help improve the travel times, diagnosis, management and disposition of these patients. LIMITATIONS: Single center study done in a tertiary care center so the results from this study may not be extrapolated to other centers.

Safe and promising outcomes of in-hospital preoperative rehabilitation for coronary artery bypass grafting after an acute coronary syndrome.

OBJECTIVE: In patients with stable hemodynamic status after an acute coronary syndrome (ACS), coronary artery bypass grafting (CABG) after preoperative investigations can provide outcomes comparable to those of emergency surgery. However, no established guidelines exist regarding the preparation period before surgery. We report the results of the use of an inpatient cardiac rehabilitation program followed by CABG after an ACS to improve post-operative outcomes and prognosis after discharge. METHODS: From 2005 to 2017, 471 patients underwent either isolated or combined CABG at our institution, and of those, the 393 who received isolated CABG were included in the analysis. Twenty-seven patients (6.9%) were admitted with ACS and underwent preoperative rehabilitation before undergoing CABG, with a subsequent review of surgical morbidity and mortality rates. Propensity score matching yielded a cohort of 26 patients who underwent preoperative rehabilitation (group A) and 26 controls (group B). Preoperative characteristics were similar between groups. RESULTS: The completion rate of the rehabilitation program was 96.3%. All programs were conducted with inpatients, with an average length of stay of 23 ± 12 days. All patients completed in-bed exercises, and 85% completed out-of-bed exercises. The 30-day postoperative mortality was 0% in both groups A and B, and the rate of postoperative major adverse cardiac or cerebrovascular events at 12 months did not differ significantly between groups (7.7% vs 3.9%, respectively; p = 1.0). The duration of mechanical ventilation (1.3 ± 0.3 vs 1.5 ± 0.3 days, respectively; p = 0.633), length of intensive care unit stay (4.4 ± 2.1 vs 4.8 ± 2.3 days, respectively; p = 0.584) and length of hospital stay (25 ± 13 vs 22 ± 9 days, respectively; p = 0.378) did not differ significantly between groups. CONCLUSIONS: No complications of preoperative rehabilitation were observed, suggesting that it is an acceptable option for patients who experience ACS and undergo CABG. These results are promising in offering more robust designs of future trials.

Troponin efficacy in the diagnosis of acute coronary syndrome in patients with chronic renal failure.

There is no consensus on whether cardiac troponins with high reliability values should be different diagnostic criteria for acute myocardial infarction in patients with and without renal dysfunction. Although it is often emphasized that the etiology of elevated troponin levels in chronic kidney disease (CKD) remains unclear, elevated cardiac troponin (cTnT) levels have been associated with increased subclinical cardiac damage in these patient groups. In this study, we investigated the value of cTnT value in diagnosing acute coronary syndrome in CKD patients with high clinical suspicion of acute coronary syndrome and without acute ST segment elevation on electrocardiogram. The aim was to prevent cardiac ischemia from being overlooked in CKD patients. Coronary angiography revealed vessel occlusion in 192 patients, and the mortality rate after treatment decisions was 6.7%. The first measured troponin results showed a significant difference in patients who did not survive, indicating the prognostic value of troponin levels. Troponin values were compared with cardiovascular pathologies obtained by angiography, and elevated troponin levels strongly correlated with pathologic angiography results. The conclusion highlighted that despite prognostic uncertainties, biomarkers used for acute myocardial infarction diagnosis in patients with renal insufficiency are reliable in those with renal dysfunction. Elevated cTnT levels in CKD patients are considered a clear marker of cardiac ischemia, emphasizing the need for careful consideration of troponin values in this population.

Early SGLT2 inhibitor use is associated with improved left atrial strain following acute coronary syndrome.

AIM: Left atrial (LA) strain, a novel marker of LA function, reliably predicts diastolic dysfunction. SGLT2 inhibitors improve heart failure outcomes, but limited data exists regarding their use in the immediate aftermath of acute coronary syndrome (ACS). We studied the effect of empagliflozin on LA strain in patients with type 2 diabetes (T2D) and ACS. METHODS: Patients with ACS and T2D were identified and empagliflozin was initiated in eligible patients prior to discharge. Patients not initiated on empagliflozin were analysed as a comparator group. A blinded investigator assessed LA strain using baseline and 3-6 month follow-up echocardiograms. RESULTS: Forty-four participants (n = 22 each group) were included. Baseline characteristics and LA strain were similar in the two groups. LA reservoir, conduit and contractile strain increased in empagliflozin group (28.0 ± 8.4% to 34.6 ± 12.2% p < 0.001, 14.5 ± 5.4% to 16.7 ± 7.0% p = 0.034, 13.5 ± 5.2% to 17.9 ± 7.2% p = 0.005, respectively) but remained unchanged in comparison group (29.2 ± 6.7% to 28.8 ± 7.0%, 12.8 ± 4.2% to 13.3 ± 4.7%, 16.7 ± 5.3% to 15.5 ± 4.5%, respectively, p = NS). The difference in change between groups was significant for LA reservoir (p = 0.003) and contractile strain (p = 0.005). CONCLUSION: In patients with ACS and T2D, addition of empagliflozin to standard ACS therapy prior to discharge is associated with improved LA function.

Temporal trends in admission for cardiac rehabilitation after an acute coronary syndrome in France from 2009 to 2021: Persistent sex, age and social disparities.

BACKGROUND: Cardiac rehabilitation after an acute coronary syndrome is recommended to decrease patient morbidity and mortality and to improve quality of life. AIMS: To describe time trends in the rates of patients undergoing cardiac rehabilitation after an acute coronary syndrome in France from 2009 to 2021, and to identify possible disparities. METHODS: All patients hospitalized for acute coronary syndrome in France between January 2009 and June 2021 were identified from the national health insurance database. Cardiac rehabilitation attendance was identified within 6 months of acute coronary syndrome hospital discharge. Age-standardized cardiac rehabilitation rates were computed and stratified for sex and acute coronary syndrome subtypes (ST-segment elevation and non-ST-segment elevation). Patient characteristics and outcomes were described and compared. Factors independently associated with cardiac rehabilitation attendance were identified. RESULTS: In 2019, among 134,846 patients with an acute coronary syndrome, 22.3% underwent cardiac rehabilitation within 6 months of acute coronary syndrome hospital discharge. The mean age of patients receiving cardiac rehabilitation was 62 years. The median delay between acute coronary syndrome hospitalization and cardiac rehabilitation was 32 days, with about 60% receiving outpatient cardiac rehabilitation. Factors significantly associated with higher cardiac rehabilitation rates were male sex, younger age (35-64 years), least socially disadvantaged group, ST-segment elevation, percutaneous coronary intervention and coronary artery bypass graft. Between 2009 and 2019, cardiac rehabilitation rates increased by 40% from 15.9% to 22.3%. Despite greater upward trends in women, their cardiac rehabilitation rate was significantly lower than that for men (14.8% vs. 25.8%). In 2020, cardiac rehabilitation attendance dropped because of the coronavirus disease 2019 pandemic. CONCLUSIONS: Despite the health benefits of cardiac rehabilitation, current cardiac rehabilitation attendance after acute coronary syndrome remains insufficient in France, particularly among the elderly, women and socially disadvantaged people.

Diagnostic and prognostic performance of the neutrophil-to-lymphocyte ratio in acute coronary syndromes: A meta-analysis of 90 studies including 45 990 patients.

BACKGROUND: Cardiovascular disease is a leading cause of mortality worldwide and is likely to rise. Acute coronary syndrome (ACS) is consequent on inflammation. As a common and cost-effective inflammatory biomarker, the neutrophil-to-lymphocyte ratio (NLR) may be beneficial in cardiovascular medicine. AIMS: This meta-analysis examines the diagnostic and prognostic performance of the NLR in ACS. METHODS: We systematically searched PubMed Central, Medline, Scopus, EMBASE, Cochrane Central Register of Controlled Trials, and Clinicaltrial.gov databases. The search spanned from databases inception to January 10, 2024. The findings were aggregated into normalized mean differences with 95% confidence intervals. RESULTS: Ninety articles, with 45 990 participants, were included. Pooled analysis of the NLR varied and was higher in ST-segment elevation myocardial infarction (STEMI) vs. non-ST-segment elevation myocardial infarction patients (4.94 ± 3.24 vs. 3.24 ± 2.74), acute myocardial infarction vs. unstable angina (4.47 ± 3.43 vs. 2.97 ± 1.58), ACS vs. stable angina (SA) (5.45 ± 4.28 vs. 2.46 ± 2.15), and ACS vs. controls (5.31 ± 4.01 vs. 2.46 ± 2.45). The NLR also was associated with ACS mortality, with survivors having lower results (3.67 ± 2.72 vs. 5.56 ± 3.93). Subanalysis showed that differences in the NLR were observed in STEMI survivors (4.28 ± 3.24 vs. 6.79 ± 3.98). Of ACS patients with major cardiovascular events (MACE) vs. without MACE, the NLR was 6.29 ± 4.89 vs. 3.82 ± 4.12. In STEMI patients, the NLR differed between those with and without MACE (6.99 ± 5.27 vs. 4.99 ± 4.12). CONCLUSIONS: The NLR is an effective tool for differentiating between different types of ACS. A high NLR is associated with ACS and increased MACE at 30 days. The NLR also appears to be a good predictor of MACE risk, at least in STEMI patients.

Validation of the ACC Expert Consensus Decision Pathway for Patients With Chest Pain.

BACKGROUND: The American College of Cardiology (ACC) recently published an Expert Consensus Decision Pathway for chest pain. OBJECTIVES: The purpose of this study was to validate the ACC Pathway in a multisite U.S. METHODS: An observational cohort study of adults with possible acute coronary syndrome was conducted. Patients were accrued from 5 U.S. Emergency Departments (November 1, 2020, to July 31, 2022). ECGs and 0- and 2-hour high-sensitivity troponin (Beckman Coulter) measures were used to stratify patients according to the ACC Pathway. The primary safety outcome was 30-day all-cause death or myocardial infarction (MI). Efficacy was defined as the proportion stratified to the rule-out zone. Negative predictive value for 30-day death or MI was assessed among the whole cohort and in a subgroup of patients with coronary artery disease (CAD) (prior MI, revascularization, or ≥70% coronary stenosis). RESULTS: ACC Pathway assessments were complete in 14,395 patients, of whom 51.7% (7,437 of 14,395) were women with a median age of 56 years (Q1-Q3: 44-68 years). Known CAD was present in 23.5% (3,386 of 14,395) and 30-day death or MI occurred in 8.1% (1,168 of 14,395). The ACC Pathway had an efficacy of 48.1% (95% CI: 47.3%-49.0%). Among patients in the rule-out zone, 0.3% (22 of 6,930) had death or MI at 30 days, yielding a negative predictive value of 99.7% (95% CI: 99.5%-99.8%). In patients with known CAD, 20.0% (676 of 3,386) were classified to the rule-out zone, of whom 1.5% (10 of 676) had death or MI. CONCLUSIONS: The ACC expert consensus decision pathway was safe and efficacious. However, it may not be safe for use among patients with known CAD.