DNA methyltransferase 3A regulates the expressions of collagens during the activation of cardiac fibroblasts / 医学研究生学报

Objective The mechanisms of methylation acting on myocardial fibrosis are not yet clear at present. The aim of this study was to investigate the role of DNA methyltransferase 3A (DNMT3A) in regulating the expressions of collagens during the activation of cardiac fibroblasts.Methods Cardiac fibroblasts were obtained from 50 neonatal mice and divided into three groups: blank control, DNMT3A overexpression plasmid (mDNMT3A-pEGFP-C3) and small interference DNMT3A siRNA. The contents of collagens in the cell supernatant were detected by ELISA. The mRNA and protein expressions of type I collagen (Col Ⅰ), type Ⅲ collagen (Col Ⅲ) and DNMT3A in the cardiac fibroblasts were determined by real-time quantitative PCR and Western blot respectively and the proliferative activity of the cardiac fibroblasts measured by CCK8 assay.Results The contents of Col I and Col Ⅲ in the cell supernatant were significantly increased in the DNMT3A overexpression plasmid group but decreased in the DNMT3A siRNA group as compared with those in the blank control (P<0.05). The expressions of Col Ⅰ, Col Ⅲ and DNMT3A were remarkably higher in the DNMT3A overexpression plasmid group but lower in the DNMT3A siRNA group than in the blank control (P<0.05). The cell activity was markedly higher in the DNMT3A overexpression plasmid group than in the empty vector plasmid and control groups (2.087±0.317 vs 1.063±0.223 and 1.082±0.207, P<0.05) but lower in the DNMT3A siRNA group (0.463±0.087) than in the latter two (P<0.05).Conclusion DNMT3A can increase the proliferation and activation of cardiac fibroblasts, upregulate the expressions of collagens and thus promote myocardial fibrosis.

Preliminary results of combined carotid endarterectomy and off-pump coronary artery bypass grafting in patients with coexistent carotid and coronary artery diseases / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Coexistent carotid and coronary artery diseases are common and patients with them remain at a high risk for perioperative stroke or myocardial infarction after coronary bypass surgery. The aim of this study was to investigate the effect of combined carotid endarterectomy (CEA) and off-pump coronary artery bypass grafting (CABG) in patients with coexistent carotid and coronary artery diseases.</p><p><b>METHODS</b>Between January 2002 and December 2007, consecutive patients with coexistent carotid and coronary artery diseases underwent one-stage unilateral CEA and off-pump CABG in Heart Institute of Nanjing First Hospital Affiliated to Nanjing Medical University. Perioperative complications were assessed and follow-up was carried out.</p><p><b>RESULTS</b>A total of 51 cases of isolated off-pump CABG and unilateral CEA, including 34 right and 17 left, were performed. The mean blocked time of carotid artery in CEA was (25.5 +/- 7.0) minutes. The mean number of distal grafts per patient was 3.30 +/- 0.45. The mean ventilation time, intensive care unit stay, and postoperative hospital stay was (11.3 +/- 5.4) hours, (2.1 +/- 0.9) days, and (12.5 +/- 6.1) days respectively. None of the patients had stroke or myocardial infarct. There was one perioperative death due to acute cardiac failure, resulting in an operative mortality of 1.96%. Follow-up was completed for 47 patients (92.16%) with a mean follow-up of (39.5 +/- 12.5) months. None of the patients manifested stroke, new angina or newly developed cardiac infarct. No late death occurred.</p><p><b>CONCLUSION</b>Combined CEA and off-pump CABG is a safe and effective procedure in selected patients with coexistent carotid and coronary artery diseases.</p>

Is the use of cardiopulmonary bypass for isolated coronary artery bypass an independent predictor of mortality and morbidity in patients with severe left ventricular dysfunction? / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Patients presenting with severe left ventricular dysfunction (SLVD) undergoing conventional coronary artery bypass grafting (CCABG) are at an increased risk of perioperative mortality and morbidity. The aim of this study was to assess the risk factors responsible for mortality and morbidity among patients with SLVD by comparing CCABG and off-pump coronary artery bypass surgery (OPCAB).</p><p><b>METHODS</b>We retrospectively evaluated 186 consecutive patients with SLVD who underwent coronary artery bypass grafting (CABG), including 102 by CCABG and 84 by OPCAB. Registry database, medical notes, and charts were studied for preoperative and postoperative data of the patients. Different variables and risk factors (preoperative, intraoperative, and postoperative) were evaluated and compared. The morbidity and mortality outcomes were compared in the two groups. The follow-up results and quality of life were assessed after surgery.</p><p><b>RESULTS</b>The two groups had similar percentage of patients with preoperative high-risk profiles and no significant differences were found between groups in baseline variables such as age or comorbidities. There was a significant difference in the number of grafts used between the two groups. CCABG patients received (3.6 +/- 0.5) grafts per patient, while OPCAB patients had (2.7 +/- 0.6) grafts (P < 0.05). Completeness of revascularization was also significantly different between the two groups (CCABG 91.1% vs OPCAB 73.8%, P < 0.05). The hospital mortality was similar in the two groups (4.8% in OPCAB vs 5.9% in CCABG). The risk-adjusted mortality, according to the calculated propensity score, did not reach statistical significance in the two groups. In this study, OPCAB seemed to have a beneficial effect on reducing reoperation for bleeding, blood transfusion requirement, and the length of stay at ICU. But the incidence of perioperative myocardial infarction was more common in the off-pump group (P < 0.05). The degree of improvement in angina and quality of life did not differ significantly between the two groups.</p><p><b>CONCLUSIONS</b>Using cardiopulmonary bypass is not an independent predictor of mortality and morbidity in patients with SLVD. Isolated CABG can be safely performed in SLVD patients with acceptable postoperative morbidity and mortality in addition to encouraging home discharge rates and higher quality of life. Therefore, CCABG remains a viable option in selected patients with SLVD.</p>

Surgical treatment of obstructive hypertrophic cardiomyopathy with ventricular septal myectomy concomitant mitral valve replacement / 中华外科杂志

<p><b>OBJECTIVE</b>To summarize the experiences and results of ventricular septal myectomy concomitant mitral valve replacement (MVR) for obstructive hypertrophic cardiomyopathy (OHCM).</p><p><b>METHODS</b>From January 2000 to June 2007, 22 patients of OHCM with moderate or severe mitral regurgitation underwent concomitant ventricular septal myectomy concomitant MVR. There were 20 male and 2 female patients. The age ranged from 28 to 51 years old with a mean of (36 + or - 5) years old. The left ventricular out tract gradient pressure (LVOTGP) was 55 to 120 mm Hg (1 mm Hg = 0.133 kPa), with a mean of (88.0 + or - 15.8) mm Hg. The manifestation of pre-operative UCG, intra-operative transesophageal echocardiography (TEE) and post-operative UCG in 10 d, 6 months and 1 year were compared and analyzed.</p><p><b>RESULTS</b>One patient died in hospital due to serious ventricular arrhythmias. The intra-operative TEE showed that the phenomenon of systolic anterior motion (SAM) of mitral valve disappeared in all patients. Twenty-one cases were followed-up. The intra-operative TEE and post-operative UCG in every period of all 21 cases survived indicated that the mean LVOTGP and interventricular septal thickness (IVST) decreased obviously (P < 0.01).</p><p><b>CONCLUSION</b>Concomitant ventricular septal myectomy concomitant MVR is an effective and safe treatment for OHCM with moderate or severe mitral regurgitation, the short and mid-term outcome is excellent.</p>

Impact of preoperative clopidogrel in coronary artery bypass grafting / 中华外科杂志

<p><b>OBJECTIVE</b>To analyze and assess the impact of clopidogrel given preoperatively in coronary artery bypass grafting (CABG) surgery.</p><p><b>METHODS</b>From January 2005 to January 2007, 440 consecutive patients undergoing CABG surgery were divided into two groups: the clopidogrel group (with clopidogrel exposure in 5 days prior to surgery, n = 90) and the control group (without clopidogrel exposure > 5 days prior to surgery, n = 350). Patients undergoing emergency surgery because of failed percutaneous transluminal coronary angioplasty and cardiogenic shock, associated valvular surgery, redo-CABG were excluded. Patients who received aspirin and/or heparin treatment before surgery were included.</p><p><b>RESULTS</b>There was no significant difference in two groups regarding age, gender,diabetes mellitus and hypertension. Compared to the control group, patients in clopidogrel group had a higher prevalence of angina class III or IV (66.7% vs. 40.0%, P < 0.01), received more often revascularization within 48 h (41.1% vs. 14.3%, P = 0.02), and had received more frequently stenting (56.7% vs. 13.4%, P < 0.01). Chest tube drainage was significantly increased during the first 24 h following CABG in the clopidogrel group (800 ml vs. 350 ml, P < 0.01). Patients of the clopidogrel group also required more transfusion of packed red blood cells and fresh frozen plasma. Overall re-exploration rate because of bleeding was remarkably higher in the clopidogrel group (4.4% vs. 1.1%, P < 0.01).</p><p><b>CONCLUSIONS</b>Clopidogrel exposure in 5 days or less prior to CABG surgery significantly increases the risk of postoperative bleeding, the need for perioperative transfusion and the incidence of re-exploration. For the elective CABG patient, we suggest that the surgery should to be performed 5 days or more after clopidogrel exposure.</p>

Application of Adjustable Interatrial Fistulization in Operation of Congenital Heart Disease Accompany with Severe Pulmonary Arterial Hypertension / 实用儿科临床杂志

Objective To investigate the method and value of adjustable interatrial fistulization in the operation of congenital heart disease(CHD) accompany with severe pulmonary arterial hypertension(PH).Methods Twenty-seven patients(19 male,8 females) accompany with severe PH were entered the study,age ranged from 4 to 14 years old,weight from 13.7 to 42.0 kilogram.The enrolled diseases included 11 cases of atrial septal defect(ASD),10 cases of ventricular septal defect(VSD),4 cases of patent ductus arteriosus(PDA),and 2 cases of Ebstein syndrome accompany with severe tricuspid insufficiency.All patients were diagnosed as CHD accompany with severe PH(bidirectional shunt)which was the contraindications for routine operation before operation through chest X-ray,electrocardiography,ultrasonic cardiography,cardiac catheteri-zation and cardiac angiography.Results With adjustable interatrial fistulization and treatment to the abnormalities,14 fistulaes were closed immediately after operation,7 fistulaes were closed 2 days after operation,3 fistulaes were closed 3 days and 1 fistulae was closed 4 days after operation and accompanied with empyema discharged initiatively.One fistula was never closed,1 case died from low cardiac output symptom.The effective rate was 92.6%,closed to that of routine operations.Conclusion Adjustable interatrial fistulization is an easy procedure,and it can decrease the danger of PH post-operation effectively and provide operation opportunity for those patients with CHD approaching terminal stage.

Coronary endarterectomy and bypass grafting without cardiopulmonary bypass for patients with diffused coronary artery disease / 中华外科杂志

<p><b>OBJECTIVE</b>To review and summarize the early outcomes and clinical experience of coronary endarterectomy (CE) and bypass grafting without cardiopulmonary bypass for patients with diffused coronary artery disease.</p><p><b>METHODS</b>From May 2003 to May 2005, 53 patients with diffused coronary artery disease underwent CE and bypass grafting without cardiopulmonary bypass. There were 41 males and 12 females aged from 55 to 79 (mean 64 +/- 7) years old. 72% patients (38/53) were in Canadian Cardiac Society (CCS) angina class III and IV. 49% (26/53) had history of myocardial infarction. Coronary angiogram revealed that 3 cases had double vessels disease and, other 50 cases had triple vessels disease with 9 left main stem disease. The left ventricular ejection fraction (LVEF) ranged from 0.26 to 0.65 (0.52 +/- 0.17). Seventy endarterectomies were performed in 53 patients totally which included 38 in left anterior descending artery (LAD), 8 in circumflex artery and 24 in right coronary artery. Five cases received on-lay venous patch after CE in LAD and then grafted by internal mammary artery (IMA) on the patch. There were 53 left IMAs, 2 radial arteries, others were great saphenous veins, the mean number of grafts was 3.8 +/- 1.1 with index of completeness of revascularization (ICR) 1.03 +/- 0.07.</p><p><b>RESULTS</b>Intra-operative graft flow-meter was used to check the flow in the grafts before chest closure. There is no death in the group. Sixty-three (90%) out of 70 grafts after CE showed a satisfactory grafts flow intra-operatively. Two patients had peri-operative myocardial infarctions but neither had hemodynamic changes. All patients discharged uneventfully with mean hospital stay 9 days postoperatively. Forty-four patients had 6 to 29 months follow-up with no angina re-occurrence. Six patients had coronary angiogram 3 to 27 months postoperatively with all patent grafts to the CE coronaries.</p><p><b>CONCLUSION</b>CE and bypass grafting without cardiopulmonary bypass is technically feasible and can be performed safely in patients with diffused coronary artery disease with increased completeness of myocardial revascularization.</p>