Myocardial infarction (MI) has the characteristics of high mortality rate, strong suddenness and invisibility. There are problems such as the delayed diagnosis, misdiagnosis and missed diagnosis in clinical practice. Electrocardiogram (ECG) examination is the simplest and fastest way to diagnose MI. The research on MI intelligent auxiliary diagnosis based on ECG is of great significance. On the basis of the pathophysiological mechanism of MI and characteristic changes in ECG, feature point extraction and morphology recognition of ECG, along with intelligent auxiliary diagnosis method of MI based on machine learning and deep learning are all summarized. The models, datasets, the number of ECG, the number of leads, input modes, evaluation methods and effects of different methods are compared. Finally, future research directions and development trends are pointed out, including data enhancement of MI, feature points and dynamic features extraction of ECG, the generalization and clinical interpretability of models, which are expected to provide references for researchers in related fields of MI intelligent auxiliary diagnosis.
Humans ; Electrocardiography ; Myocardial Infarction/diagnosis* ; Recognition, Psychology

OBJECTIVE: To investigate the value of T2 mapping in the assessment of myocardial changes and prognosis in patients with acute ST segment elevation myocardial infarction (STEMI). METHODS: A retrospective study was conducted. A total of 30 patients with acute STEMI admitted to Tianjin First Central Hospital from January 2021 to March 2022 were enrolled as the experimental group. At the same time, 30 age- and sex-matched healthy volunteers and outpatients with non-specific chest pain with no abnormalities in cardiac magnetic resonance (CMR) examination were selected as the control group. CMR was performed within 2 weeks after the diagnosis of STEMI, as the initial reference. A plain CMR review was performed 6 months later (chronic myocardial infarction, CMI). Plain scanning includes film sequence (CINE), T2 weighted short tau inversion recovery (T2-STIR), native-T1 mapping, and T2 mapping. Enhanced scanning includes first-pass perfusion, late gadolinium enhancement (LGE), and post-contrast T1 mapping. Quantitative myocardial parameters were compared between the two groups, before and after STEMI myocardial infarction. The receiver operator characteristic curve (ROC curve) was used to evaluate the diagnostic efficacy of native-T1 before myocardial contrast enhancement and T2 values in differentiating STEMI and CMI after 6 months. RESULTS: There were no statistically significant differences in age, gender, heart rate and body mass index (BMI) between the two groups, which were comparable. The native-T1 value, T2 value and extracellular volume (ECV) were significantly higher than those in the control group [native-T1 value (ms): 1 434.5±165.3 vs. 1 237.0±102.5, T2 value (ms): 48.3±15.6 vs. 21.8±13.1, ECV: (39.6±13.8)% vs. (22.8±5.0)%, all P < 0.05]. In the experimental group, 12 patients were re-examined by plain CMR scan 6 months later. After 6 months, the high signal intensity on T2-STIR was still visible, but the range was smaller than that in the acute phase, and the native-T1 and T2 values were significantly lower than those in the acute phase [native-T1 value (ms): 1 271.0±26.9 vs. 1 434.5±165.3, T2 value (ms): 34.2±11.2 vs. 48.3±15.6, both P < 0.05]. ROC curve analysis showed that the area under the ROC curve (AUC) of native-T1 and T2 values in differentiating acute STEMI from CMI was 0.71 and 0.80, respectively. When native-T1 cut-off value was 1 316.0 ms, the specificity was 100% and the sensitivity was 53.3%; when T2 cut-off value was 46.7 ms, the specificity was 100% and the sensitivity was 73.8%. CONCLUSIONS The T2 mapping is a non-invasive method for the diagnosis of myocardial changes in patients with acute STEMI myocardial infarction, and can be used to to evaluate the clinical prognosis of patients.
Humans ; ST Elevation Myocardial Infarction/diagnosis* ; Contrast Media ; Prognosis ; Retrospective Studies ; Magnetic Resonance Imaging, Cine/methods* ; Gadolinium ; Myocardium/pathology* ; Myocardial Infarction ; Predictive Value of Tests

OBJECTIVE: To evaluate the accuracy of cardiac troponin (cTn) levels in the diagnosis of acute myocardial infarction (AMI) in patients with chronic kidney disease (CKD) and explore a potential strategy for improving the diagnostic accuracy. METHODS: We retrospectively analyzed the data from patients with high-risk chest pain admitted in Zhujiang Hospital from January, 2018 to December, 2020, including 126 patients with and 272 patients without CKD, and 122 patients diagnosed to have AMI and 276 patients without AMI. The baseline clinical data of the patients and blood test results within 12 h after admission were collected. RESULTS: In patients without AMI, cTnT level was significantly higher in those with co-morbid CKD than in those without CKD (P < 0.001), and showed a moderate negative correlation with eGFR (r_s=- 0.501, P < 0.001), while cTnI level did not differ significantly between the two groups (P=0.72). In patients with CKD, the optimal cutoff level was 0.177 μg/L for cTnT and 0.415 ng/mL for cTnI for diagnosis of AMI, for which cTnI had a higher specificity than cTnT. The diagnostic model combining both cTnT and cTnI levels [P=e^Y/(1+ e^Y), Y=6.928 (cTnT)-0.5 (cTnI)-1.491] had a higher AUC value than cTn level alone. CONCLUSION In CKD patients, the cutoff level of cTn is increased for diagnosing AMI, and cTnI has a higher diagnostic specificity than cTnT. The combination of cTnT and cTnI levels may further improve diagnostic efficacy for AMI.
Humans ; Retrospective Studies ; Myocardial Infarction/diagnosis* ; Comorbidity ; Troponin T ; Troponin I ; Renal Insufficiency, Chronic/diagnosis* ; Biomarkers

OBJECTIVE: We aimed to assess the feasibility and superiority of machine learning (ML) methods to predict the risk of Major Adverse Cardiovascular Events (MACEs) in chest pain patients with NSTE-ACS. METHODS: Enrolled chest pain patients were from two centers, Beijing Anzhen Emergency Chest Pain Center Beijing Bo'ai Hospital, China Rehabilitation Research Center. Five classifiers were used to develop ML models. Accuracy, Precision, Recall, F-Measure and AUC were used to assess the model performance and prediction effect compared with HEART risk scoring system. Ultimately, ML model constructed by Naïve Bayes was employed to predict the occurrence of MACEs. RESULTS: According to learning metrics, ML models constructed by different classifiers were superior over HEART (History, ECG, Age, Risk factors, & Troponin) scoring system when predicting acute myocardial infarction (AMI) and all-cause death. However, according to ROC curves and AUC, ML model constructed by different classifiers performed better than HEART scoring system only in prediction for AMI. Among the five ML algorithms, Linear support vector machine (SVC), Naïve Bayes and Logistic regression classifiers stood out with all Accuracy, Precision, Recall and F-Measure from 0.8 to 1.0 for predicting any event, AMI, revascularization and all-cause death ( vs. HEART ≤ 0.78), with AUC from 0.88 to 0.98 for predicting any event, AMI and revascularization ( vs. HEART ≤ 0.85). ML model developed by Naïve Bayes predicted that suspected acute coronary syndrome (ACS), abnormal electrocardiogram (ECG), elevated hs-cTn I, sex and smoking were risk factors of MACEs. CONCLUSION Compared with HEART risk scoring system, the superiority of ML method was demonstrated when employing Linear SVC classifier, Naïve Bayes and Logistic. ML method could be a promising method to predict MACEs in chest pain patients with NSTE-ACS.
Humans ; Acute Coronary Syndrome/epidemiology* ; Bayes Theorem ; Feasibility Studies ; Risk Assessment/methods* ; Chest Pain/etiology* ; Myocardial Infarction/diagnosis*

Objective: To explore associations between lipoprotein-associated phospholipase A2 (Lp-PLA2) and the risk of cardiovascular events in a Chinese population, with a long-term follow-up. Methods: A random sample of 2,031 participants (73.6% males, mean age = 60.4 years) was derived from the Asymptomatic Polyvascular Abnormalities Community study (APAC) from 2010 to 2011. Serum Lp-PLA2 levels were determined by enzyme-linked immunosorbent assay (ELISA). The composite endpoint was a combination of first-ever stroke, myocardial infarction (MI) or all-cause death. Lp-PLA2 associations with outcomes were assessed using Cox models. Results: The median Lp-PLA2 level was 141.0 ng/mL. Over a median follow-up of 9.1 years, we identified 389 events (19.2%), including 137 stroke incidents, 43 MIs, and 244 all-cause deaths. Using multivariate Cox regression, when compared with the lowest Lp-PLA2 quartile, the hazard ratios with 95% confidence intervals for developing composite endpoints, stroke, major adverse cardiovascular events, and all-cause death were 1.77 (1.24-2.54), 1.92 (1.03-3.60), 1.69 (1.003-2.84), and 1.94 (1.18-3.18) in the highest quartile, respectively. Composite endpoints in 145 (28.6%) patients occurred in the highest quartile where Lp-PLA2 (159.0 ng/mL) was much lower than the American Association of Clinical Endocrinologists recommended cut-off point, 200 ng/mL. Conclusion Higher Lp-PLA2 levels were associated with an increased risk of cardiovascular event/death in a middle-aged Chinese population. The Lp-PLA2 cut-off point may be lower in the Chinese population when predicting cardiovascular events.
1-Alkyl-2-acetylglycerophosphocholine Esterase/blood* ; Asians ; Cardiovascular Diseases/diagnosis* ; China/epidemiology* ; Female ; Humans ; Longitudinal Studies ; Male ; Middle Aged ; Mortality ; Myocardial Infarction/blood* ; Predictive Value of Tests ; Risk Factors ; Stroke/blood*

The postmortem diagnosis of acute myocardial infarction (AMI), especially the postmortem diagnosis of early AMI that died immediately after onset or within 1 hour, has always been a difficulty in forensic identification. This article reviews the forensic application of diagnosis and analysis methods for AMI postmortem diagnosis including autopsy imaging, histomorphology, immunohisto-chemistry, biochemical marker and molecular biology diagnosis, and explores the feasible scheme of early postmortem diagnosis in AMI.
Autopsy ; Biomarkers ; Forensic Medicine ; Forensic Pathology/methods* ; Humans ; Myocardial Infarction/diagnosis* ; Postmortem Changes

OBJECTIVE: To assess the value of wearable 12-lead electrocardiogram (ECG) devices in pre-hospital diagnosis of acute ST segment elevation myocardial infarction (STEMI). METHODS: This analysis was conducted among 441 patients selected from the''National ECG Network'', who used wearable 12-lead ECG device with critical situation warning of ST change between January 2019, and August, 2021.The general characteristics, response time and complaints of the patients with STEMI were analyzed.The accuracy of pre-hospital diagnosis of STEMI was compared between clinician's interpretation of ECGs and AI diagnosis by the wearable ECG device. RESULTS: In 89 of the patients, a pre-hospital diagnosis of STEMI was made by physicians based on ECGs from the wearable devices, and 58 of them sought medical attention after online warning, with a referral rate of 65.17%.The average time for diagnostic assessment of the ECGs was 153.02 s, and the average time for confirmation of the diagnosis was 178.06 s.The sensitivity for pre-hospital diagnosis of STEMI by clinician's interpretation of the ECGs and by AI diagnosis was 100% and 88.37%, respectively, with a specificity of 95.40% and 79.31%, respectively.The pre-hospital diagnosis by clinicians and AI diagnosis of STEMI both showed a high consistency with the subsequent definite clinical diagnosis of STEMI. CONCLUSION Wearable 12-lead ECG devices can accurately record ECG characteristics of STEMI patients outside the hospital and allow immediate data uploading for an early diagnosis.The diagnoses of STEMI made based on AI technology are highly consistent with those by clinicians, demonstrating excellent clinical performance of the wearable ECG devices.
Humans ; ST Elevation Myocardial Infarction/diagnosis* ; Electrocardiography ; Arrhythmias, Cardiac ; Wearable Electronic Devices ; Hospitals

The de Winter electrocardiogram pattern is an acute ST-segment elevation myocardial infarction equivalent, however this specific electrocardiogram change is easily ignored by clinicians. The de Winter electrocardiogram pattern in patients with acute chest pain mostly indicates sub-complete or complete occlusion of the left anterior descending or the diagonal branch. Patients with acute chest pain and such electrocardiographic finding should undergo emergency coronary angiography immediately to determine the coronary condition, and reperfusion therapy should be performed as soon as possible to reduce the incidence of adverse cardiovascular events.
Anterior Wall Myocardial Infarction ; Cognition ; Coronary Angiography ; Electrocardiography ; Humans ; ST Elevation Myocardial Infarction/diagnosis*

OBJECTIVES: To explore the electrocardiogram manifestations and clinical characteristics of patients with the de Winter electrocardiogram pattern. METHODS: This retrospective study was performed on acute coronary syndrome (ACS), patients with culprit lesion in left anterior descending branch (LAD), who admitted to Yongchuan Hospital of Chongqing Medical University from August 2017 to October 2018. Patients were categorized into those with or without the de Winter electrocardiogram pattern. The characteristics of de Winter electrocardiogram were analyzed by the clinical data of the patients. RESULTS: Among 230 patients with left anterior descending branch lesion, 14 (6%) had the de Winter electrocardiogram pattern. Compared with the control group, patients with de Winter electrocardiogram pattern were younger [(53.86±10.26) years old vs (67.20± 11.60) years old CONCLUSIONS The de Winter electrocardiogram pattern syndrome in patients with acute chest pain mostly indicates that the left anterior descending or the diagonal branch is subtotal or completely occluded, which is a special ST-segment elevation myocardial infarction equivalent and should attract the clinicians' extensive attention.
Acute Coronary Syndrome/diagnosis* ; Adult ; Aged ; Coronary Angiography ; Electrocardiography ; Humans ; Middle Aged ; Retrospective Studies ; ST Elevation Myocardial Infarction

Objective To summarize cases of acute myocardial infarction (AMI) after tranexamic acid (TXA) administration. Methods Electronic databases were searched to identify all case reports presenting AMI after use of TXA. Two authors independently extracted data of patients' manifestation, examinations, medical history, treatment and outcome. Results Our search yielded seven case reports including seven patients. Among the seven reports, two were from USA, and the other five were from India, Turkey, UK, Italy and France, respectively. Of the seven patients aged between 28- and 77-year-old who developed AMI after TXA, five patients were female and two were male. TXA was prescribed for four patients to reduce surgical bleeding, for two patients to treat menorrhagia and for one patient to manage hemoptysis. The diagnosis of AMI was made based upon patients' symptoms, ECG, myocardium-specific enzymes, and confirmed by coronary angiography. Coronary stents were placed in four patients, for whom anti-platelet and anti-coagulation drugs were prescribed. No death or major cardiovascular events were reported during hospitalization and follow-up. Conclusion These case reports suggested a possible association of TXA administration and an increased risk of AMI, even in patients with relatively low thrombotic risk.
Adult ; Aged ; Blood Loss, Surgical/prevention & control* ; Female ; Humans ; Male ; Middle Aged ; Myocardial Infarction/diagnosis* ; Risk Factors ; Tranexamic Acid/therapeutic use*