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This study aimed to examine the functional role of microRNA-20 (miR-20) and its potential target,Kir6.1,in ischemic myocardiocytes.The expression of miR-20 was detected by real-time PCR.Myocardiocytes were stained with terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) reagent for apoptosis evaluation.Western blotting was used to detect the Kit6.1 protein in ischemic myocardiocytes transfected with miR-20 mimics or inhibitors.Luciferase reporter gene assay was performed to confirm the targeting effect of miR-20 on KCNJ8.The results showed that miR-20 was remarkably down-regulated,while the KATP subunit Kir6.1 was significantly up-regulated,during myocardial ischemia.The miR-20 overexpression promoted the apoptosis of ischemic myocardiocytes,but showed no such effect on normal cells.Under ischemic condition,myocardiocytes transfected with miR-20 mimics expressed less Kir6.1.On the contrary,inhibiting miR-20 increased the expression of Kir6.1 in the cells.Co-transfection of miR-20 mimics with the KCNJ8 3’-UTR plasmid into HEK293 cells consistently produced less luciferase activity than transfection of the plasmid alone.It was concluded that miR-20 may regulate myocardiac ischemia by targeting KATP subunit Kir6.1 to accelerate the cell apoptosis.Therefore miR-20 may serve as a therapeutic target for myocardial ischemic disease.
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Objective To evaluate the effects of preventive cardiac pacing on acute inferior wall myocardiac infarction ( AIMI ) . Methods A total of 52 patients were given preventive cardiac pacing before Percutaneous coronary intervention (PCI) (group T),while another 68 patients were not (group N).Heart rate and average blood pressure level before reperfusion, average blood pressure level after reperfusion,TIMI flow grade before and after reperfusion,the incidence of malignant ventricular arrhythmia after reperfusion and adverse cardiovascular events during hospitalization were compared in two groups. Results There were no significant differences in heart rate before reperfusion , average blood pressure levels before and after reperfusion , and the TIMI flow grade before and after reperfusion between two groups. The malignant ventricular arrhythmia after reperfusion in group T was significantly higher than that in group N while heart failure and nonfatal myocardial infarction were no significantly different between them. Mortality rate and mortality rate of cardiovascular disease in group T were higher than those in group N, but there were no significant differences between them. Conclusions The temporary cardiac pacing has no additional preventive effect on hemodynamic , but increases the occurrence of malignant ventricular arrhythmia , and the risk of death and cardiovascular events.
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We report a case of a 69-year-old man presenting with acute right chest pain radiating to the right shoulder. Physical examination revealed a right sided apex beat with a palpable liver on the left side. Reversed normalizing electrocardiogram are presented, allowing for correct diagnosis of an acute anterior myocardial infarction. Dextrocardia with situs inversus is an uncommon congenital condition, the patient also diagnosed hypertrophic cardiomyopathy by two dimensional echocardiography. Successful percutaneous coronary intervention was performed and the patient was discharged after uneventful recovery.
Subject(s)
Humans , Cardiomyopathy, Hypertrophic , Chest Pain , Dextrocardia , Echocardiography , Electrocardiography , Liver , Myocardial Infarction , Percutaneous Coronary Intervention , Physical Examination , Shoulder , Situs InversusABSTRACT
BACKGROUND: We determined the protective effects of a high dose of ulinastatin on myocardial and renal function in patients undergoing aortic valve replacement with cardiopulmonary bypass (CPB). METHODS: Sixty patients were assigned randomly to either the ulinastatin group (n = 30) or the control group (n = 30). In the ulinastatin group, ulinastatin (300,000 U) was given after the induction of anesthesia, ulinastatin (400,000 U) was added to the CPB pump prime, and then ulinastatin (300,000 U) was administered after weaning from CPB. In the control group, the same volume of saline was administered at the same time points. Creatine kinase-MB levels were assessed 1 day before surgery, and on the first and second postoperative day (POD 1 and 2). Serum creatinine and cystatin C levels were assessed 1 day before surgery, upon intensive care unit arrival, and on POD 1 and 2. The level of plasma neutrophil gelatinase-associated lipocalin was assessed before induction of anesthesia, upon ICU arrival, and on POD 1. RESULTS: No significant differences were observed in serum levels of creatine kinase-MB and biomarkers of renal injury between the two groups at any point during the study period. CONCLUSIONS: Ulinastatin showed no cardiac or renal protective effects after CPB in patients undergoing aortic valve replacement.
Subject(s)
Humans , Anesthesia , Aortic Valve , Biomarkers , Cardiac Surgical Procedures , Cardiopulmonary Bypass , Creatine , Creatinine , Cystatin C , Glycoproteins , Intensive Care Units , Lipocalins , Neutrophils , Plasma , WeaningABSTRACT
Objective To determine whether autologous skeletal myoblasts implantation improves the cardiac function after myocardial infarction and the possible mechanism. Methods Myocardial infarction was induced by ligation of the left anterior descending coronary artery in rabbits. At 2 weeks, 1. 34 × 107 to 1.75 × 107 autologous skeletal myoblasts were infused into the lesion via direct intramuscular injection. In the control group, the postinfarction hearts were infused with medium alone. Buxco invasive cardiac function testing and histopathological examination were utilized to evaluate the functional and structural changes in the myocardium 4 weeks later. Results Both maximum rising rate of the left intraventricular pressure [+dp/dtmax,( 1 217.77 +89.91 )mmHg/s vs. (897.83 ±70.04) mmHg/s] and maximum falling rate of the left intraventricular pressure [- dp/dtmax,( -1174.58 ± 91.5 ) mmHg/s vs. ( - 753.67 ± 69.66 ) mmHg/s] were improved in the myoblast transplanted group compared with medium infusion group. The positive desmin immunostaining skeletal myofibers in the myocardium were found throughout the infracted areas and the border zone. Conclusion Autologous skeletal myoblasts can establish muscle tissue when transplanted into postinfarction hearts, and this mucle can treat myocardiac infarction effectively.
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Objective To investigate the cause of high cardiovascular lethality in patients with diabetics mellitus. Methods Sections from autopsied coronary arteries and myocardium of dead patients with non-insulin-dependent diabetics mellitus and 12 dead control subjects were used for histomorphometric studies. Results The coronary atherosclerotic lesion in diabetics patients was not different in severity from those in controls. Nor was there difference in number of myofibers or diameters of myocardic fibers and capillaries.But the capillary density and the ratio of capillary number to myocardic fiber number in diabetics group were significeantly reduced compared with control group(P<0.0 l),and the capillary basement membrane in the former was significantly thicker than in the latter(P<0.01).Conclision The decrease in number of capillaries and the thickening of basement membrane enhance myocardiac vulnerability to further ischemia and hypoxia,which may undelie high lethality of myocardiopathy in diabetic patients.
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Objective To investigate the myocardial protective effect of adenosine preconditioning against ischemia-reperfusion injury in patients who were undergone valve replacement during cardiac pulmonary bypass.Methods 42 patients scheduling for valve replacement operation were divided randomly into two groups:experiment group(n=23) and control group(n=19).Adenosine preconditioning were performed in experiment group before cardiac pulmonary bypass.To estimate the plasma level of cardiotroponin I (cTnI),creatine kinase isoenzyme (CK-MB ),radialis arterial blood was drown at following time points respectively: before operation,30 minutes before and after aortic clamp,1 hour and 3 hours after aortic opened.Meanwhile the rate of heart spontaneous rebeating,defibrillation,arrhythmia and cardiac inotropic agents used and its duration were recorded.Results The elevated range of plasm cTnI and CK-MB in experiment group were obviously lower than that in control group.In experiment group,the rate of heart spontaneous rebeating were higher,but the frequency of defibrillation,arrhythmia and the cardiac inotropic agents used and its duration were lower than those of control group.Conclusion Adenosine preconditioning has notable clinical protective effects on myocardial ischemia-reperfusion injury in patients undergone valve replacement during cardiac pulmonary bypass.
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BACKGROUND: Desflurane and sevoflurane have been shown to induce pharmacologic preconditioning in experimental studies. The present study was aimed at comparing the myocardial protective effects of these two halogenated anesthetics in terms preconditioning induction. METHODS: Three groups of Sprague-Dawley rat hearts (n = 10 each) were perfused with oxygenated modified Kreb's solution using a Langendorff perfusion device. All groups underwent 30 minutes of global ischemia and 60 minutes of reperfusion after a stabilization period of 30 minutes. Before ischemia, hearts underwent a preconditioning period consisting of either no inhalation for 20 minutes (control group), or 15 minutes of either MAC desflurane or sevoflurane followed by 5 minutes of washout. Left ventricular end systolic pressure (LVESP), left ventricular end diastolic pressure (LVEDP), heart rate (HR) and maximal rate of change of ventricular pressure (dP/dt) were measured at after inhalation, before ischemia, and 5 minutes, 30 minutes and 60 minutes after reperfusion. Coronary sinus effluent also was measured. Infarct size was measured by triphenyl tetrazolium staining. RESULTS: LVESP and dP/dt were decreased in the control group, but remained unchanged in the desflurane and sevoflurane groups during the reperfusion period. LVEDP was increased in all groups, but the magnitude of the increase was smaller in the desflurane and sevoflurane groups than in the control group during the reperfusion period. HR was increased in the control group, but remained unchanged in the desflurane and sevoflurane groups during the reperfusion period. Coronary blood flow was decreased in all groups. Infarct size for the two anesthetics were smaller than in the control group. Differences in hemodynamics was observed between the desflurane and sevoflurane group at any time. CONCLUSIONS: Desflurane and sevoflurane had similar myocardial preconditioning effects in isolated rat heart.
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Animals , Rats , Anesthetics , Blood Pressure , Coronary Sinus , Heart Rate , Heart , Hemodynamics , Inhalation , Ischemia , Ischemic Preconditioning, Myocardial , Oxygen , Perfusion , Rats, Sprague-Dawley , Reperfusion Injury , Reperfusion , Ventricular PressureABSTRACT
PURPOSE: Minocycline appears to reduce the mortality rate of patients with myocardial infarction. Therefore, the cardioprotective effects of minocycline through reduction of apoptosis were studied in a rat myocardiac cell culture induced by hypoxia. METHODS: Cultured cells from the hearts of Sprague-Dawley rats were divided into two sets of groups: normoxia groups treated with 5% O2 and hypoxia groups treated with 1% O2. After several days of incubation, the control groups were not treated with minocycline, while the sample groups were treated with 1 mug/mL of minocycline. The damaged cells were observed under a microscope, while apoptosis was detected using a Tdt-mediated dUTP nick and labeling(TUNEL) assay control-stained with 4'-6'-diamidino-2-phenylindole-2HCl(DAPI). RESULTS: In normoxia, the control group showed a statistically significant difference from the sample group treated with 1 mug/mL of minocycline. In addition, in hypoxia, there was also a statistically significant difference between the two groups. When comparing the normoxia and hypoxia groups to each other, there was a statistically significant difference between the control groups and sample groups. CONCLUSION: Minocycline was found to be protective for heart in normoxia and in hypoxia in the model of rat myocardiac cell culture.
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Animals , Humans , Rats , Hypoxia , Apoptosis , Cell Culture Techniques , Cells, Cultured , Heart , Minocycline , Mortality , Myocardial Infarction , Rats, Sprague-DawleyABSTRACT
BACKGROUND: Hyperhomocysteinemia can be treated and is more preventable compared to the classical risk factors such as age, sex, smoking, obesity, diabetes mellitus, hypertension and hyperlipidemia. METHODS: Serum homocysteine levels were analyzed with fluorescence polarized immunoassay (IMx, Abbott Diagnostics) for 63 patients with acute myocadiac infarction (AMI) and 43 controls who did not have coronary arterial disease from 1997 to 1998. Medical records were reviewed to compare the classical risk factors between the two groups. RESULTS: The mean homocysteine level of AMI was 9.3 +/-5.3 micronmol/L, which is slightly lower than 9.8+/-5.8 micronmol/L in the control group (P>0.05). Other risk factors were not significantly different between the two groups with the exception of serum cholesterol level. CONCLUSIONS: It is concluded that hypercholesterolemia is an important risk factor for AMI, while serum homocysteine level is not, as far as this study goes. Well planned follow up studies are needed to establish the degree to which homocysteine is a risk factor for AMI.
Subject(s)
Humans , Cholesterol , Diabetes Mellitus , Fluorescence , Homocysteine , Hypercholesterolemia , Hyperhomocysteinemia , Hyperlipidemias , Hypertension , Immunoassay , Infarction , Medical Records , Obesity , Risk Factors , Smoke , SmokingABSTRACT
113 patients with myocardiac infarctus, admitted from Jan 2000 to November 2002, among them 51-i.e 45,1% patients (group 1) were benefited by classic method of treatment, 41 patients i.e 36,3% (group 2) by classic method combining fibrinolyse medicaments. It appears that in subject of group 2 hyprotension/fluctation, heart failure, pulmonary edema less developed than group 1. It appears that post-treatment dysrythmia in group 2 less and mildly developed than group 1. The difference of two groups on the rate of clinical arterial unclog was not considerable (33,3% - 34,1%) mainly because of heart failure. It appears that in group 2 the rate of death is lower and heart failure after infarctus was not commonly reported. This is a safe, simple and easy treament without adverse reaction
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Myocarditis , Therapeutics , Myocardial InfarctionABSTRACT
BACKGROUND: Chlamydia pneumoniae can cause chronic inflammation in the arterial wall. C. pneumoniae infection has been investigated as a new risk factor for acute myocardiac infarction (AMI), afatal outcome of coronary artery occlusion. METHODS: IgG and IgM for C. pneumoniae using micro-immunofluorescence were evaluated in 80 AMI patients and 46 controls without coronary arterial disease. RESULTS: Chronic infection, defined by equal or higher than 1: 32 titers of IgG of C. pneumoniae, was observed in 51.3% (41/80) in AMI and 17.4% (8/46) in controls (P<0.05). None of the subjects showed acute infection, defined by equal or higher than either 1: 16 of IgM or 1: 512 of IgG of C. pneumoniae. CONCLUSIONS: Chronic C. pneumoniae infection was significantly more common in AMI patients compared to the controls.
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Humans , Chlamydia , Chlamydophila pneumoniae , Coronary Vessels , Immunoglobulin G , Immunoglobulin M , Infarction , Inflammation , Pneumonia , Risk FactorsABSTRACT
Objective To investigate the effects of simvastatin on the abatement of the mRNA,protein expression of RhoA and the improvement of the cardiac remodeling and cardiac disfunction after the myocardiac infarction in rats.Methods Rats were divided into 3 groups: the control group,the myocardiac infarction group and Simvastatin intervened group.After 8 weeks,cardiac weight index and hemodynamics were observed,mRNA and protein expression of RhoA in cardiac muscles was measured. Results Compared with the control group,the cardiac weight index and the mRNA and protein expression were increased in rats with myocardiac infarction and the hemodynamics was worsened(P
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Objective To study the regularities of myocardiac cells with age increasing. Methods 30 male rats were used in the experiment and divided into three groups:infant group (20\|25 day), young group (3\|5 month) and old group (13\|15 month). Routine paraffine sections were made for PTAH staining and data of cell area, nuclear area, ratio of nucleus to cytoplasm, nuclear ellipticity were measured by image computer analyzer. Results With advancing age:1^Cell area and nuclear area became larger; the ratio of nucleus to cytoplasm was declined; nuclear ellipticity turned high. 2^The cell area of ventricular myocytes was bigger than that of atrial myocytes, the cell area of left atrial myocytes and left ventricular myocytes was bigger than that of right ones, and the cell area of interventricular septum was between that of right ventricular myocytes and left ones. 3^Myocardiac cells became thicker and longer; intercalated disc got distinct and complex.Conclusion The growth of nuclei seem to slower than that of myocardiac cells; the morphology of nucleus changes from round to ellipse; Round nucleus is one of important features of young cells; the cells in atrium is younger than that of ventricle.
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@#ObjectiveTo investigate application of exercise stress test after acute myocardial infarction(AMI). Methods32 patients with AMI performed exercise stress test adopted the Bruce protocol in 16 days-8weeks after onset, at the same time cardiac functional capacity was measured.ResultsThe stress test was positive in 17 cases, whose cardiac functional capacity was 1.5-7 METs,and it was negative in 15 cases, whose cardiac functional capacity is 4-12 METs.Conclusions①Second class amount limited exercise stress test is safe to adaptive AMI patients. ②Cardiac functional capacity measurement is benefit to instruct patient rehabilitation exercise. ③Exercise stress test is valuable to estimate prognosis of AMI.
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To study the effects of astragaloside Ⅳ, which was obtained from Astragalus membranaceus Bge., on myocardiac dynamics and cardiac function on normal and cardiac depressant rat. Methods Left ventricular pressure (LVP) and differential value of dp/dt were recorded by left ventricular catherization to observe the effect of 1 mg/kg iv astragaloside Ⅳ on normal and cardiac depressant rat induced by iv 0.75 mg/kg of Propanolol. Results Astragaloside Ⅳ decreased heart rate slightly, and showed inotropic activity by increasing dp/dtmax significantly, with improvement of cardiac diastolic function. It shortened the time constant (T) and caused no obvious change on the tension time index (TTI) in normal rat. These results suggested that astragaloside Ⅳ did not increase cardiac oxygen consumption while exerting its inotropic effect. Conclusion Astragaloside Ⅳ can improve both cardiac systolic and diastolic functions, and may be used as a candidate for the treatment of cardiac disfunction.
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Objective To investigate the clinical characteristics, TCM syndrome differen tiation and short_term prognosis of painless acute myocardiac infarction (AMI). Methods Restrospective analysis was carried out in 32 patients with painless AMI (Group A) and 30 cases of painful AMI in the same period served as Group B. Results In Group A, clinical manifestations were latent, infarct places mai nly located in the inferior wall, right ventricle and posterior wall of the hear t ( 65.6% ), and yang_Qi deficiency syndrome and Qi_yin defic iency syndrome occupied 65.6% of painless AMI. Blood stasis syn drome and phlegm syndrome occupied 70.0% of painful AMI. The co ncurrent incidence of diabetes mellitus was higher in Group A than Group B. So d id the mortality and the incidence of heart failure. Cardiogenic shock and heart failure were the main death causes of painless AMI. Conclusion The above r esults will supply evidence for the combined treatment of painless AMI.
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A 44 years old woman was admitted to Inha University hospital in semicomatose state. An electrocardiogram (ECG), taken in the emergency room, showed ST segment elevation in the precordial leads. She underwent a urgent echocardiography. It showed that there was akinesia of anteroseptal segment from the mid left ventricle to the apex and inferior segment from the mid left ventrile to the lower mid left ventricle. With the impression of acute myocardial infarction (AMI), she underwent a urgent coronary angiography. There was no significant luminal narrowing of the right or the left coronary arteries but the left ventriculography revealed akinesia of anterolateral and diaphragmatic segments of the left ventricle. Computerized tomography (CT) of the brain, taken shortly after coronary angiography, showed subarachnoid hemorrhage. The abnormal ECG and echocardiography findings, simulating acute myocardial infarction, were assumed to be caused by coronary vasospasm derived from subarachnoid hemorrhage accompanied by massive adrenergic discharge.
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Adult , Female , Humans , Brain , Coronary Angiography , Coronary Vasospasm , Coronary Vessels , Echocardiography , Electrocardiography , Emergency Service, Hospital , Heart Ventricles , Intracranial Hemorrhages , Myocardial Infarction , Phenobarbital , Subarachnoid HemorrhageABSTRACT
Object To study the effects of astragaloside Ⅳ, which was obtained from Astragalus membranaceus Bge., on myocardiac dynamics and cardiac function on normal and cardiac depressant rat Methods Left ventricular pressure (LVP) and differential value of dp/dt were recorded by left ventricular catherization to observe the effect of 1 mg/kg iv astragaloside Ⅳ on normal and cardiac depressant rat induced by iv 0 75 mg/kg of Propanolol Results Astragaloside Ⅳ decreased heart rate slightly, and showed inotropic activity by increasing dp/dt max significantly, with improvement of cardiac diastolic function It shortened the time constant (T) and caused no obvious change on the tension time index (TTI) in normal rat These results suggested that astragaloside Ⅳ did not increase cardiac oxygen consumption while exerting its inotropic effect Conclusion Astragaloside Ⅳ can improve both cardiac systolic and diastolic functions, and may be used as a candidate for the treatment of cardiac disfunction
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Objective:To investigate the protective effect of Intravenous Injection of Radix Astragali seu Hedysari on acute myocardiac infarction (AMI) in anesthetized dogs. Methods: Twenty health dogs were treated by ligating descending anterior of coronary with two-step method. The changes of electrocardiogram before and after ligation were recorded. After 4 hours myocardium were taken out and dyed with NBT to make sure of the extent of myocardiac infarction.Results: Intravenous Injection of Radix Astragali seu Hedysari could decrease the lethality of AMI, ameliorated ST changes on electrocardiogram induced by AMI, and reduced infarction area. Conclusions: Intravenous Injection of Radix Astragali seu Hedysari is effective in the treatment of AMI in anesthetized dogs.