ObjectiveTo improve and assess the method of establishing myocardial infarction model in New Zealand rabbits. MethodsA total of 60 New Zealand rabbits were randomly divided into two groups:the left anterior descending coronary artery was ligated in a LAD group (n=30); the left circumflex coronary artery was ligated in a LC group (n=30). Electrocardiogram (ECG), ultrasound cardiogram (UCG), hemodynamics and histology procedures were performed to detect the changes of cardiac structure and function after myocardial infarction induced by LAD and LC ligation. ResultsSuccess rate of the LC group was significantly higher than that in the LAD group (P < 0.01), but the survival rate in the LC group was slightly lower than the LAD group (P < 0.05); ECG within 24 h and 1 week after surgery showed that the average values of ST segment elevation in the LC group were significantly higher than that in the LAD group (P < 0.05); UCG and hemodynamics results showed cardiac function in the LAD group did not decrease significantly (P > 0.05). In contrast, cardiac function in the LC group were significantly decreased (P < 0.05). Histopathologic analysis showed that the area of myocardial infarction in the LC group was significantly larger than that in the LAD group (P < 0.01). ConclusionThe myocardial infarction induced by the left circumflex coronary artery ligation is more consistent than that induced by the left anterior descending coronary artery ligation, suggesting that the former is a more appropriate experimental model for evaluations.
Objective To report a reliable left heart failure model in sheep using selected ligation of the diagonal branch. Methods Four male sheep were used. After a left anterior thoracotomy in sheep, the diagonal branch of coronary artery was ligated at a point approximately 40% of the distance from the apex to the base of the heart. Hemodynamic and echocardiography measurements were done preligation, 30 minutes and 7 days after the coronary artery of diagonal branch ligation. The electrocardiograms were obtained as needed, and cardiac function was also evaluated. The sheep were killed for postmortem examination of their hearts. Results Four sheep survived the experimental procedures. Comparing with before surgery, systemic arterial blood pressure and cardiac output were decreased, pulmonaryartery systolic pressure, pulmonary capillary wedge pressure and central venous pressure were increased at 30 min and 7 days after selected ligation of the coronary artery of diagonal branch; left ventricular end-diastolic dimension and left ventricular end-systolic dimension were increased; left ventricular ejection fraction and left ventricular fractional shortening were also decreased (Plt;0.05). Conclusion A reliable ovine model of left ventricular failure using selected ligation of the diagonal branch of the coronary artery can be achieved. This animal model is comparable to the clinical correlation.
Objective To investigate the incidence and risk factors of non-alcoholic fatty liver disease (NAFLD) in patients with myocardial infarction. Methods A total of 634 patients with myocardial infarction from Beijing Anzhen Hospital were asked to take liver and gallbladder ultrasonography during hospitalization, and then divided into the NAFLD and non-NAFLD groups. The incidence and risk factors of the two groups were then analyzed. Results The incidence of NAFLD was 52.2% (331/634). Both body mass index (BMI) and serum alanine aminotransferase of the NAFLD group were higher than those of non-NAFLD group, with significant difference (Plt;0.05). The incidence of NAFLD was positively increased following the severity of coronary diseases (χ2=7.275, P=0.03). The result of multivariable logistic regression analysis showed BMI, multi-vessel lesions of coronary disease, and left main coronary artery lesion were the independent risk factors of NAFLD. Conclusion The myocardial infarction patients who are particularly complicated by overweight, multi-vessel lesions and left main coronary artery lesion have a higher incidence of NAFLD.
Objective To investigate the effect of bone marrow mesenchymal stem cell (MSCs) transp1antation combined with transmyocardial drilling revascularization (TMDR) and degradable stent on myocardium revascu1arization after acute myocardial infarction(AMI), and to provide the experimental evidence for surgical treatment of myocardial infarction. Methods After established models of AMI, the 24 pigs were divided into four groups with random number table, 6 pigs each group. Control group: only established models of AMI; MSCs group: AMI immediately followed by MSCs implantation; TMDR combined with stent group: AMI followed by TMDR and absorbable basic fibroblast growth factor (bFGF) stent implantation; MSCs combined with TMDR and stent group: AMI followed by TMDR and absorbable bFGF stent implantation, and then MSCs implantation. Three months after operation, the infarcted areas and vessel density in infarcted zone were detected by histopathology method. Results Three months after operation, the histopathological examination showed that infarcted areas in MSCs group, TMDR combined with stent group, and MSCs combined with TMDR and stent group were decreased as compared with control group （27.9%±3.1% vs. 48.9%±2.7%，P=0.000；20.3%±1.7% vs. 48.9%±2.7%，P=0.000；12.5%±1.9% vs. 48.9%±2.7%，P=0.000）; and vessel density was further increased （8.4±1.2/HP vs.4.5±14/HP，P=CM(1583mm] 0.001；11.5±2.6/HP vs.4.5±1.4/HP，P=0.001;15.6±1.4/HP vs.4.5±1.4/HP，P=0.000）. Conclusion [CM)]MSCs transplantation combined with TMDR and absorbable bFGF stents implantation could significantly reduce the infarction areas, increase the vessel density. This method may enhance the efficacy of MSCs transplantation in acute cardiac infarction model, which provide a new ideas for the surgical treatment of myocardial infarction.
Objective To report an acute ischemic left ventricular heart failure model of safe, simple, relatively steady, and reproducible in sheep. Methods Fourteen female sheep with a body weight of 36.80±3.43kg were used in this study. Heart failure model was induced by partial occluding the middle left circumflex coronary artery （LCX） combined with pacemaker-induced tachycardia. Hemodynamic measurement was done before and after heart failure, myocardial examination was observed. Results Heart failure model was induced successfully in 10 sheep. Cardiac output dropped from 3.74±0.48L/min to 2.02±0. 51L/min （P〈0. 01）, mean arterial pressure decreased from 116. 10± 14.15 mmHg（1kPa = 7.5mmHg） to 68. 10± 14. 72mmHg （P〈0.01）, central venous pressure rose from 7. 10±2.18mmHg to 10. 70± 3.50 mmHg （P〈0.05）, right ventricular end-diastolic pressure increased from 6.10±3.57mmHg to 9.90±4.41mmHg（P〈0.05）, left atrial pressure increased from 8.10±2.13 mmHg to 12.00± 4.57mmHg （P〈0. 01 ）, and left ventricular end-diastolic pressure increased from 8. 50± 4. 17mmHg to 13.10± 10. 64mmHg（P〉 0. 05）. The myocardial ultrastructure injuries was marked. Conclusions Acute ischemic left ventricular heart failure could be induced by partial occlusion of the middle LCX combined with pacemaker-induced taehyeardia in sheep. This model is simple, easy to manipulate, relatively steady, and reproducible . It may be used for assessing cardiac assist devices.
ObjectiveTo investigate the surgical methods and efficacy of myocardial infarction combined with ventricular septal perforation.MethodsThe clinical data of 60 patients with myocardial infarction combined with ventricular septal perforation admitted to the Department of Cardiac Surgery, Beijing Anzhen Hospital, Capital Medical University, from 2009 to 2018 were retrospectively analyzed. There were 39 males and 21 females, aged 63.3±8.3 years.ResultsAmong the 60 patients, 43 (71.7%) patients were perforated in the apex, 11 (18.3%) in the posterior septum and 6 (10.0%) in the anterior septum. There were 24 (40.0%) patients of single coronary artery disease. Fourteen (23.3%) patients received intra-aortic balloon counterpulsation before surgery. The waiting time from ventricular septal perforation to surgery was 48.3 (3-217) d. All patients underwent ventricular septal perforation repair, among whom 53 (88.3%) patients received ventricular aneurysm closure or resection, and 49 (81.7%) patients received coronary artery bypass graft with an average of 2 distal anastomoses during the same period. Perioperative complications in the hospital included 8 (13.3%) deaths, 8 (13.3%) heart failure, 5 (8.3%) ventricular fibrillation, 3 (5.0%) pericardial tamponade, and 11 (18.3%) secondary thoracotomy and 11 (18.3%) residual shunt. Except for 8 patients who died in the hospital, the other 52 cured and discharged patients were followed up. The median follow-up time was 4.9 years. The 2-year and 5-year survival rate of the patients was 95.8%, and the 8-year survival rate was 89.0%. Major adverse cardiovascular events incidence was 19.2%, including 3 (5.8%) deaths, 5 (9.6%) heart failure, 2 (3.8%) myocardial infarction, and 4 (7.7%) cerebrovascular events.ConclusionFor patients with ventricular septal perforation after myocardial infarction, surgery is an effective treatment method. Although the perioperative mortality rate is high, satisfactory long-term results can be achieved by carefully choosing the operation timing and methods.
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.
Objective To summarize the experiences of surgical treatment for post infarction ventricular aneurysm and mi tral regurgitation， thus to improve surgical curative effect and survival rates . Clinical data of 37 patients with myocardial infarction complicated with ven tricular aneurysm and severer than moderate mitral regurgitation were retrospectively an alyzed between December 2000 and June 2007, all 37 patients underwent coron ary artery bypass grafting and reconstruction of left ventricular after aneurysm resection, mitral valve repair or replacement. Results Three patients died during hospital stay after surgery,mortality rate was 81%, of th em two died in renal failure, one died in brain complications.Thirty patients we re followed up, followup rate was 88.2%(30/34), with 4 patients missed. Follow up time ranged from 1 month to 6 years after surgery, 2 patients died in foll o wup period, of them one died in anticoagulant treatment failure complicated w ith the large cerebral infarction, one died of lung infection and heart failure. The inner diameter of le ft atrium and enddiastolic left ventricle reduced obviously than those before operation （30.1±3.5mm vs.39.3±3.7mm, P=0.004;48.4±4.3mm vs.61.2±5.1mm, P=0.003）by color doppler echocardiography examination at 6th month a fter su rgery.There was no obvious change in size of untouched ventricular aneurysm(diam eterlt;5cm). No regurgitation or slight regurgitation were observed in 12 patient s, mild regurgitation was observed in 2 patients and moderate in 1 patients. Conclusion According to different types of post infarctio n ventricular aneurysm and mitral regurgitation, constitution o f different surgical treatment programs, can result in favorable early and long-term curative effect. There’s marked improvement in most patients’cardiac f unction and survival rate.
Electrocardiogram (ECG) signal is an important basis for the diagnosis of arrhythmia and myocardial infarction. In order to further improve the classification effect of arrhythmia and myocardial infarction, an ECG classification algorithm based on Convolutional vision Transformer (CvT) and multimodal image fusion was proposed. Through Gramian summation angular field (GASF), Gramian difference angular field (GADF) and recurrence plot (RP), the one-dimensional ECG signal was converted into three different modes of two-dimensional images, and fused into a multimodal fusion image containing more features. The CvT-13 model could take into account local and global information when processing the fused image, thus effectively improving the classification performance. On the MIT-BIH arrhythmia dataset and the PTB myocardial infarction dataset, the algorithm achieved a combined accuracy of 99.9% for the classification of five arrhythmias and 99.8% for the classification of myocardial infarction. The experiments show that the high-precision computer-assisted intelligent classification method is superior and can effectively improve the diagnostic efficiency of arrhythmia as well as myocardial infarction and other cardiac diseases.
Objective To evaluate the cardiac protection function of high thoracic epidural anesthesia (HTEA) for patients with acute coronary syndrome or heart failure. Methods A literature search was conducted with computerized database on PubMed, EBSCO, Springer, Ovid, and CNKI from 1990 to May 2010. Further searches for articles were conducted by checking all references describing cardiac protection studies with HTEA. All included articles were assessed and data were extracted according to the standard of Cochrane review. The homogeneous studies were pooled using RevMan 4.2.10 software. Results A total of 28 articles involving 1 041 patients were included. The results of meta-analyses showed that, a) cardiac function: HTEA could significantly improve ejection fraction of left ventricle (WMD= –?10.28, 95%CI –?14.14 to –?6.43) and cardiac output (WMD= –?1.26, 95%CI –?1.63 to –?0.89), contract left ventricular diastolic dimension (WMD= 5.02, 95%CI 3.72 to 6.32), increase E peak (WMD= –?17.50, 95%CI –?29.40 to –?5.59) and decrease A peak (WMD= 27.36, 95%CI 24.46 to 30.26); b) ischemic degree for patients with heart failure: the change of NST-T (WMD= 1.45, 95%CI 1.12 to 1.78) and ∑ST-T (WMD= 1.02, 95%CI 0.78 to 1.26) got significantly decreased after HTEA; c) ischemic degree for patients with acute coronary syndrome: HTEA could obviously lessen the times (WMD= 4.24, 95%CI 0.48 to 8.00) and duration (WMD= 23.29, 95%CI 4.66 to 42.11) of myocardial ischemia, decrease the times of heart attack (WMD= 3.44, 95%CI 0.92 to 5.97), and decrease the change of NST-T (WMD= 1.10, 95%CI 0.84 to 1.36) and ∑ST-T (WMD= 1.33, 95%CI 1.01 to 1.65); d) hemodynamic change for patients with acute coronary syndrome: HTEA could obviously decrease heart beat (WMD= 8.44, 95%CI 3.81 to 13.07) and systolic arterial pressure (WMD= 2.07, 95%CI 0.81 to 3.34), but not decrease the diastolic blood pressure (WMD= 2.06, 95%CI –?0.52 to 4.64) so as to avoid influencing the infusion of coronary artery; and e) influence on Q-T interval dispersion: HTEA could significantly decrease Q-Td (WMD= 9.51, 95%CI 4.74 to 14.27), Q-Tcd (WMD= 11.82, 95%CI 5.55 to 18.09), and J-Td (WMD= 9.04, 95%CI 2.30 to 15.79). Conclusions High thoracic epidural anesthesia can obviously improve the systolic and diastolic function of left ventricle, decrease the heart beat and stabilize hemodynamic change, lessen the times and duration for myocardial ischemia, reserve the ST segment change, contract Q-T interval dispersion, which has to be further proved with more high quality studies.