Model of cardiac arrest in rats established by modified transcutaneous electrical stimulation on epicardium / 中华急诊医学杂志

Objective To establish the cardiac arrest (CA) model in rats by modified transcutaneous electrical stimulation on epicardium. Methods This study was performed in the Emergency Medicine laboratory in Union Hospital, Tongji Medical College, Huazhong University of Science and Technology. After 10 Sprague-Dawley male rats weighing 330-380 g were anesthetized, two acupuncture needles connected to the anode and cathode of a stimulator were transcutaneously inserted into the epicardium as electrodes. The puncture points were located quantitatively according to the anatomical structure of the rat chest. The electrical stimulation was maintained for 3 minutes to induce ventricular fibrillation(VF). Cardiopulmonary resuscitation (CPR) included chest compressions, intravenous adrenaline and defi brillation operated at 6 min after a period of nonintervention. Results CA was induced after the implement of the effective electrical stimulation in all ten rats in this experiment. The average current intensity to induce VF was (1.80 ± 0.59) mA, the average time to induce CA was (5.07 ± 2.37)s,the average time of the total electrical stimulation was(187.50 ± 12.75)s and the total time of CA was 6 min. At the end of the electrical stimulation, 9 rats presented VF and 1 rat showed pulseless electrical activity. The restoration of spontaneous circulation was achieved in all 10 rats. The average time of CPR was(190.90±68.60) s, the mean numbers of defi brillation were(1.20 ± 0.63) , and he average number of adrenaline application were (1.20 ± 0.42) times. Neither visible hemorrhage on epicardium nor gross pulmonary congestion was observed. Conclusions The modified transcutaneous electrical stimulation on epicardium to produce CA model in rats is an easily applicable and effective technique. This model may provide an alternative for experimental research of CPR.

Correlation of epicardium adipose tissue volume with blank period atrial fibrillation recurrence after first radiofrequency ablation / 中国医师进修杂志

Objective To study the correlation of epicardium adipose tissue (EAT) volume with bland period atrial fibrillation (AF) recurrence after first radiofrequency ablation (RA). Methods The clinical data of 85 patients with AF were retrospectively analyzed. The EAT volume was measured by CT scanning. The patients were followed up for 6-18 months after first RA. Among the patients, 27 cases were found to have bland period AF recurrence (observation group), and 58 cases were not found to have bland period AF recurrence (control group). The EAT volume of 2 groups was compared and analyzed. Results The total EAT volume and left atrial EAT volume in observation group were significantly higher than those in control group:(118.6 ± 29.2) cm3 vs. (94.3 ± 27.1) cm3 and (28.9 ± 9.0) cm3 vs. (22.7 ± 7.3) cm3, and there were statistical differences (P<0.05). The multivariate Logistic regression analysis result showed that total EAT volumes and left atrial EAT volumes were the independent risk factors for blank period AF recurrence (OR=1.053 and 1.128, 95%CI 1.010-1.079 and 1.032-1.224, P<0.05). The AF incidence of long-term recurrence in observation group was significantly higher than that in control group: 40.7% (11/27) vs. 15.5% (9/58), and there was statistical difference (χ2 = 6.031, P<0.05). Conclusions The AF is easier to recur during blank period after first RA in AF patients with a larger total EAT volume and a larger left atrial EAT volume.

The Association between Subclinical Hypothyroidism and Epicardial Adipose Tissue Thickness

BACKGROUND AND OBJECTIVES: Subclinical hypothyroidism (SH) is considered to be a potential risk factor for cardiovascular disease. Epicardial adipose tissue (EAT) thickness is also closely related to cardiovascular disorders. The aim of this study was to evaluate whether SH is associated with higher EAT thickness. SUBJECTS AND METHODS: Fifty-one consecutive patients with SH and 51 healthy control subjects were prospectively enrolled into this trial. Thyroid hormone levels, lipid parameters, body mass index, waist and neck circumference, and EAT thickness measured by echocardiography were recorded in all subjects. RESULTS: Mean EAT thickness was increased in the SH group compared to the control group (6.7+/-1.4 mm vs. 4.7+/-1.2 mm, p<0.001). EAT thickness was shown to be correlated with thyroid stimulating hormone level (r=0.303, p=0.002). Multivariate logistic regression analysis revealed that EAT thickness was independently associated with SH {odds ratio (OR): 3.87, 95% confidence interval (CI): 1.92-7.78, p<0.001; OR: 3.80, 95% CI: 2.18-6.62, p<0.001}. CONCLUSION: Epicardial adipose tissue thickness is increased in patients with SH compared to control subjects, and this increase in EAT thickness may be associated with the potential cardiovascular adverse effects of SH.

Clinical research on radiofrequency catheter ablation for treating epicardial accessory pathway / 重庆医学

Objective To investigate the efficacy and safety of radiofrequency catheter ablation for treating epicardial accessory pathway .Methods 8 patients with unsuccessful endocardial ablation of accessory pathway were mapped within coronary venous si-nus or middle cardiac vein and the radiofrequency catheter ablation was performed by the temperature control electrode .Results Ablation in 8 cases was successfully performed within coronary sinus or middle cardiac vein .There were no complications in all pa-tients .Conclusion Radiofrequency catheter ablation of epicardial accessory pathway within coronary sinus and middle cardiac vein is safe and effective .

Study on the relationship between echocardiographic epicardial fat thickness and the severity of coronary heart disease / 中国基层医药

Objective To investigate the correlation between epicardial fat thickness (EAT) and the risk factors of coronary artery disease (CAD) as well as the severity of coronary lesions with echocardiography,Methods According to the results of coronary angiography,80 patients underwent coronary angiography were divided into coronary heart disease group (CHD group,4 6 cases) and without coronary heart disease group (control group,34cases),and according to coronary artorrythe severity,CHD goup was divided into subgroups of single-vessel disease (24 cases) and multivessel disease subgroup(22 cases).Tho epioardial fat thickness on the free wall of the right ventricle was measured at end-systole from the para-sterna,long-axis vlews.The relationship between EAT and the risk factors of CAD (such as age,gender,hypercholesterolemia,hypertenston,diabetes,smoking,family CAD history) as well as the severity of coronary lesions were analyzed.Results EAT in multivessel disease CAD group [(8.85 ± 1.44)mm] was significantly higher than that in single vessel CAD group[(6.86 ± 1.09) mm] and control group [(4.58 ± 1.12) mm] (all P ＜ 0.01).EAT was significantly related with the risk factors of CAD.Although the risk factors of CAD such as age,blood glucose,blood pressure were adjusted,EAT was still independently associated with CAD (OR:5.394,95 ％ CI:1.700 ～ 17.1 12,P =0.004).Concluslon The level of EAT is significantly correlated with CAD and the severity of coronary lesions.

Clinical application of intraoperative epicardial echocardiography in cardiac valve surgery / 中华超声影像学杂志

Objective To evaluate the clinical value of epicardial echocardiographic examination in cardiac valve surgery.Methods Epicardial echocardiography were performed in 46 patients undergoing valvular plasty or valvular replacement surgery to estimate the function of valve and left ventricle and residual shunt during cardiac surgery.Results Twelve cases of 46(26.1％)showed abnormality during cardiac surgery.Two cases of 15 patients performed valvuloplasty were changed to valvular replacement because of remarkable regurgitation of native valves.There was 1 case of periprosthetic leakage,3 cases of left atrial appendage thrombus,1 case of patent foramen ovale and 5 cases of low ejection of left ventricle in all 31 cases of valvular replacement.Conclusions Epicardial echocardiograpyc examination is an effective examination in cardiac valve surgery with clearly image,simplicity operation and promptness.

Rat models of cardiac arrest induced by transcutaneous electrical stimulation on the epicardium / 中华急诊医学杂志

Objective To establish a new model of cardiac arrest (CA) in rats by transcutaneous electrical epicardium stimulation. Method Two acupuncture needles connected to the anode and cathode of a stimulator were transcutaneously inserted into the epicardium as electrodes. The stimulating current was steered to the epicardium and the stimulation was maintained for 3 minutes to induce CA. Cardiopulmonary resuscitation (CPR) was performed at 6 minutes after a period of nonintervention. Results The success rate of induction was 12/20 at the current intensity of 1 mA; and reached 20/20 when the current intensity was increased to 2 mA. The average time from the electrical stimulation to CA induction was (5. 10 ± 2. 81) seconds. When the electrical stimulation stopped, 18/20 rats had ventricular fibrillation and 2/20 rats had pulseless electrical activity. CPR was performed for averagely 207.4 ( ± 148.8) seconds. The restoration of spontaneous circulation was 20/20. The death rate within 4 hours after CA was 5/20, and the 72-hour survival rate was 10/20. There were only two cases of complications, a minor muscle contraction and a minor lung lobe injury. Conclusions The model of CA in rats induced by transcutaneous electrical epicardium stimulation is a stable model that requires low-intensity current and has fewer complications.

Relationship between the Echocardiographic Epicardial Adipose Tissue Thickness and Serum Adiponectin in Patients with Angina

BACKGROUND: It is still unknown whether increased cardiac adiposity is related to the risk factors of coronary artery disease (CAD). We measured epicaridal adopose tissue (EAT) and mediastinal adipose tissue (MAT) using echocardiography and examined their correlations with CAD and serum adiponectin. METHODS: One hundred fifty three patients who underwent elective coronary angiography for chest pain were measured cardiac adiposity by transthoracic echocardiography. The correlations of cardiac adipose tissue with the presence and severity of CAD and the serum adiponectin level were examined. RESULTS: EAT was thicker in patients with CAD (1.8+/-1.4 vs. 3.8+/-1.9 mm, p<0.001), but MAT was not different according to the presence of CAD (2.9+/-2.8 vs. 3.5+/-2.5 mm, p=0.121). EAT showed a significant positive correlation with age (r=0.225, p=0.005), homocystein (r=0.289, p=0.001), fasting glucose (r=0.167, p=0.042), and fibrinogen (r=0.218, p=0.009), and a significant negative correlation with serum adiponectin (r=-0.194, p=0.016). EAT thickness (OR 11.53, 95% CI; 3.61-36.84, p<0.001) and low serum adiponectin (OR 2.88, 95% CI; 1.02-8.15, p=0.046) were independent predictors of obstructive CAD. However, MAT thickness was not associated with CAD. CONCLUSION: EAT was associated with the severity and risk factors of CAD and correlated with serum adiponectin level. In contrast with EAT, MAT was not associated with CAD and adiponectin.

A Case of Constrictive Pericarditis Associated With Huge Epicardial Fat Volume

Massive deposits of fat around heart are seen in overweight persons and are associated with coronary artery disease. Investigators have focused on the clinical significance of epicardial fat with respect to metabolic effects such as insulin resistance and inflammation, but the mechanical effects, such as constriction, have been largely ignored. We present an unusual case of a 59-year-old woman with obesity and diabetes mellitus who had been undergoing peritoneal dialysis due to end-stage renal disease, and who developed constrictive pericarditis, possibly secondary to extensive epicardial fatty accumulation.

Echocardiographic Epicardial Fat Thickness on Short Term Prognosis in Patients with Acute Coronary Syndrome

BACKGROUND: Previously, the authors revealed that epicardial fat thickness was significantly correlated with the severity of coronary artery disease in patients with known coronary artery disease. We evaluated whether echocardiographic epicardial fat thickness was associated with short term prognosis in patients with acute coronary syndrome. METHODS: Two hundred and sixty five consecutive acute coronary syndrome (ACS) patients who underwent successful coronary stenting were studied. Epicardial fat thickness on the free wall of right ventricle was measured at end-diastole from the parasternal long-axis views of three cardiac cycles. 30 days follow-up was obtained in all patients and clinical outcomes were compared with epicardial fat thickness. RESULTS: Mean value of epicardial fat thickness was 5.36 mm (range 0.44 to 16.55 mm). Major adverse cardiac events (MACE) were developed in 19 patients (7.2%) during 30 days; 2 cases of cardiac death, 11 of non fatal Q wave myocardial infarction (QMI), 4 of revascularization and 2 of ischemic stroke. Incidence of occlusion by thrombi (4.5% vs. 21.2%, p=0.016), Gensini's score (44.52+/-31.06 vs. 61.00+/-30.68, p=0.027) and epicardial fat thickness (5.19+/-2.13 vs. 7.51+/-3.87 mm, p=0.018) were significantly higher in patients with MACE than those without MACE. Significant correlations were demonstrated between epicardial fat thickness and age (r=0.193, p=0.002), fibrinogen (r=0.145, p=0.022) and LDLcholesterol (r=0.136, p=0.027). Multivariate analysis showed that epicardial fat thickness (OR 1.479, 95% CI 1.183-1.848, p=0.001) was an independent predictor of 30 days MACE. CONCLUSION: Epicardial fat thickness was significantly correlated with short term prognosis in patients with ACS.

Protective effects of total glycosides of Pacony on acute myocardial ischemia in dogs / 吉林大学学报(医学版)

Objective To study the protective effects of total glycosides of Pacony(TGP) on acute myocardial infarction in dogs.Methods Thirty domestic dogs were randomly divided into 5 groups(6 in each group): model control group,positive control group(ISM),and TGP groups with doses of 2.0,4.0,and 8.0 mg?kg~(-1),respectively.The descending branch of left coronary artery was ligated to construct the model of myocardial infarction in the anesthetic thoraco-opened dogs.The effect of TGP on epicardium electrocardiogram(EECG),myocardial infarction size(MIS) and serum myocardial enzymes were observed.Results Compared with controls,the ischemia degree(∑-ST,P

The effect of running training on regional cardiac myosin isozyme composition in rats / 体力科学

We examined the effect of running training on regional cardiac myosin isozyme composition in rats. Male Sprague-Dawley strain rats (4 weeks old) were used, and divided into two groups: sedentary control (C) and trained (T) groups. The T group was trained by treadmill running (40 m/min, 1h/day, 5 days/week, for 12 weeks) . At 16 weeks old, their hearts were excised. The left ventricle was separated into the subendocardium (Endo) and subepicardium (Epi) by dissecting the ventricle at the mid-wall. The ventricular myosin isozymes were examined by electrophoresis on pyrophosphate gel under non-dissociating conditions. The results showed the following: 1) The relative heart weight of the T group was significantly higher than the C group. 2) Left ventricular myosin isozyme composition showed a region-specific distribution in the C rats, and the proportion of V3 myosin or β-myosin heavy chain in the Endo was significantly higher than that of the Epi. However, the training had no effect on the cardiac myosin isozyme in either portion. 3) The activity of citrate synthase did not show transmural gradient in the ventricle of C animals. Training had no effect on the activities of either portion. 4) The activity of lactate dehydrogenase (LDH) showed transmural gradient in the ventricle of C rats. Training-induced changes in the activity of LDH were found in both portions, therefore, training abolished the transmural gradient in the activity of LDH, suggesting a corresponding redistribution of the myocardial work load.<BR>These results indicate that running training might induce the redistribution of the myocardial work load, whereas the stimulation apparently has no effect on the regional distribution of cardiac myosin isozyme composition.

MORPHOGENESIS OF THE HEART AND THE FORMATION OF THE EPICARDIUM OF CHICKEN EMBRYO / 解剖学报

The morphogenesis of the heart and the formation of the epicardium were studied with SEM, TEM and light microscopy. The results are as follows:1. There are two stages in the development of chicken heart: First is the formation of cardiac loop. In certain places, the sulcus appears outside, and the cresta appears inside during this stage. The formation of the cardiac loop indicates the establishment of the anlagen of the heart; Second is the differentiation of the anlagen, including the septation of the heart and the shift of each part of the heart. The shift of the atrium and the conus results from the shift of the right and left ventriculum. 2. The epicardium is not differcntiatcd from the myocardium, but formed from the mesenchymal cells which proliferate in front of the sinus venosus. These cells migrate and cover the entire surface of the myocardium.