It is widely believed that thrombus detachment from left atrial appendage (LAA) is closely related to cerebral embolism in patients with the increased risk of stroke in atrial fibrillation (AF) patients. About 30% AF is generated in LAA. Thus, LAA intervention may reduce the thromboembolism and AF recurrence in AF patients. Currently, more and more physicians are interested in LAA intervention for the treatment of AF. This review focuses on research progress of the LAA intervention in surgical treatment of AF.
Atrial fibrillation is one of the most common complications after coronary artery bypass grafting (CABG), with the occurrence rate of approximate 30%, which leads to hemodynamic instability, reduces survival rate, prolongs hospitalization, and increases patients' economic burden. Previous numerous studies have shown lots of preoperative, intra-operative and postoperative factors can predict the occurrence of new onset atrial fibrillation after CABG. If we can identify the specific patients at high risk for developing atrial fibrillation before operation, we may prevent atrial fibrillation more effectively, avoiding unnecessary prophylactic treatment and its risk. This review only focuses on research progress of preoperative predictors.
Tetralogy of Fallot is the most common cyanotic congenital heart disease. The pathological anatomy changes include ventricular septal defect, right ventricular outflow tract stenosis, aortic stradding and right ventricular hypertrophy. At present, the diagnostic criteria and treatment strategies of this disease are basically unified. However, there are controversies about the timing and method of surgical treatment. Based on the evidence-based information provided in the literature and the opinions of domestic experts of China, we formulate a consensus of Chinese experts to further standardize the surgical treatment of tetralogy of Fallot.
Abstract： Objective To study the effect of different numbers of bone marrow mesenchymal stem cells（MSCs） transplanted into rats with pulmonary arterial hypertension （PAH）induced by monocrotaline（MCT）and their influence on the expression of endothelin-1（ET-1）. Methods Forty healthy male Wistar rats（weight，from 180 to 250 g） were divided into four groups by random number table（n=10）：group A：Wistar rats were intraperitoneally injected with MCT 60 mg/ kg， and then injected with 1×106 MSCs via the external jugular vein；group B：Wistar rats were intraperitoneally injected with MCT 60 mg/kg，and then injected with 5×105 MSCs via the external jugular vein；MCT group：Wistar rats were intraperitoneally injected with MCT 60 mg/kg， and then injected with equal amount of PBS via the external jugular vein； control group：Wistar rats were intraperitoneally injected with equal amount of saline and then injected with equal amount of PBS via the external jugular vein. Four weeks after MSCs transplantation，right ventricular systolic pressure（RVSP） and ventricular weight ratio of right ventricle/ （left ventricle＋ventricular septum）were measured. Histomorphology of lung tissue was observed. Genetic expression of ET-1 in lungs and serum peptide of ET-1 were also measured. Results Four weeks after MSCs transplantation，both RVSP and ventricular weight ratio decreased significantly in rats of group Acompared with those of MCT group（RVSP：35.8±4.2 mm Hg vs. 47.2±10.1 mm Hg，P＜ 0.01； ventricular weight ratio：0.357±0.032 vs. 0.452±0.056，P＜0.01）， but these two parameters didn’t decrease significantly in rats of group B（P＞ 0.05）. By histopathological staining， the percentage of medial wall thickness of the pulmonary arterioles was significantly less in rats of group A than that of MCT group（19.7%±3.0% vs. 26.8%±3.6%， P＜ 0.01）. There was no statistical difference in the percentage of medial wall thickness of the pulmonary arterioles between group B and MCT group. Reverse transcriptase-polymerase chain reaction （RTase-PCR）results showed that ET-1messenger ribonucleic acid（mRNA）expression was highest in MCT group and MSCs transplantation significantly decreasedits expression in group A， while its expression was similar between group B and MCT group. The expression ofET-1 in plasma was also significantly decreased in group A than that in MCT group. Conclusion Intravenous MSCs transplantation can significantly inhibit MCT-induced PAH，and reduce both ET-1 mRNA expression in lung and ET-1 peptide level in plasma. It’s a better choice to transplant 1×106 MSCs to inhibit PAH in rats.
Abstract: Objective To explore the surgical procedures and cerebral protection and improve surgical results by summarizing the experiences of surgical treatment of 68 patients of De Bakey Ⅰ aortic dissection. Methods We retrospectively analyzed the clinical data of 68 patients (including 45 males and 23 females aged 29 to 72 years with an age of 44.5±17.2 years) with De Bakey Ⅰ aortic dissection who were treated in the General Hospital of Shenyang Command between May 2004 and April 2010. Acute aortic dissection (occurring within 2 weeks) was present in 57 patients and chronic aortic dissection in 11. The intimal tear was located in the ascending aorta in 45 patients, in the aortic arch in 12 and in the descending part of the aortic arch in 11. Thirtyfive patients underwent emergency operation and 33 underwent selected or limited operation. The operations were performed under hypothermic circulation arrest plus selective antegrade cerebral perfusion or right vena cave retrograde cerebral perfusion to protect the brain. Total arch replacement and stented elephant trunk were performed in 25 patients, Bentall operation with concomitant total arch replacement and stented elephant trunk in 16 patients, pure right semi aortic arch replacement and stented elephant trunk in 15 patients, total aortic arch replacement in 7 patients, right semi aortic arch replacement and stented elephant trunk in 3 patients, and Cabrol operation with concomitant aortic conduit with valve and total arch replacement and stented elephant trunk in 2 patients. Results Five patients (4 with acute aortic dissection and 1 with chronic aortic dissection) died with an operative mortality of 7.4%(5/68). The causes of death were anastomotic bleeding during surgery in 1 patient, postoperative low cardiac output syndrome and malignant arrhythmia in 2, acute renal failure in 1 and cerebral complications in 1. During perioperative period, psychotic symptoms occurred in 5 patients, pericardial effusion in 2 patients, hoarseness in 6 patients and poor wound healing in 1 patient. All of them were cured before dehospitalization. Sixty patients (95.2%, 60/63) were followed up for 2 months to 6 years with the other 3 patients lost. During the ollow-up, sudden death occurred to 1 patient with unknown reasons, and 1 patient had pericardial effusion and symptoms improved with relevant treatment. All the other patients followed up had a good quality of life with significant improvement of heart function. Fiftyfour patients had a heart function of New York Heart Association class Ⅰ and 5 had a function of class Ⅱ. Conclusion The surgical treatment for De Bakey Ⅰ aortic dissection should be active. The beneficial results can be obtained with best choice of operative procedures, methods of cerebral protection, and adequate treatment of complications of operation.
Objective To observe the morphology and growing status of mesenchymal stem cells(MSCs) of human bone marrow in vitro, in order to confirm that MSCs of human bone marrow are ideal seed cells and provide basic theory for further MSCs research. Methods The methods of density gradient centrifugation with lymphocyte separation medium for human and adherent filtration were used to isolate and purify MSCs of human bone marrow. We observed the cellular growth status and morphology of the primary MSCs and the surface antigens of second passage MSCs were tested. Results The primary culture cells fused into monolayer after 14-16 d. The passage cells kept the same morphological characteristics of primary culture cells. Ultrastructure of the second passage MSCs showed that the shape of nuclei was irregular, there were multiple nucleoli in some of the nuclei, and morphological differentiation of intracytoplasm organelles was immature. The growth curve of the first, fifth and tenth passage cells showed a logarithmic growth at day 3, a peak growth at day 5, and no clones occurred after tenth passage. Cloning efficiency of first passage, fifth passage and tenth passage was respectively 25.83%±2.93%, 14.67%±1.63% and 4.67%±0.52%. Test of MSCs phenotypic characteristics showed a high homogeneity among the cells and surface antigen profiles were positive for CD29, CD44 and negative for CD34, CD45. Conclusion The methods of density gradient centrifugation with lymphocyte separation medium for human and adherent filtration are simple, economic and efficient to isolate and purify MSCs from human bone marrow. With a high proliferating ability in vitro, MSCs from human bone marrow are ideal seed cells for tissue engineers.
Abstract： Objective To study the changes of the cyclic adenosine monophosphate (cAMP) and protein kinase A (PKA) expression of isolated rat hearts after diazoxide preconditioning (DPC), and to explore the possible mechanism of cAMP signaling pathway in myocardial protection by DPC. Methods Isolated working heart Langendorff perfusion models of 40 Wistar rats were set up and were divided randomly into four groups. For the ischemia reperfusion injury(I/R) group (n=10), 30 min of equilibrium perfusion was followed by a 60 min reperfusion of KrebsHenseleit (K-H) fluid. The DPC group (n=10) had a 10 min equilibrium perfusion and two cycles of 5 min of 100 μmol/L diazoxide perfusion followed by a 5 min diazoxidefree period before the 30 min ischemia and the 60 min reperfusion of K-H fluid. The blank control group (control group, n=10) and the Dimethyl Sulphoxide(DMSO) group (n=10) were perfused with the same treatment as in the DPC group except that diazoxide was replaced by natriichloridum and DMSO respectively. The activity of creatine kinase (CK) in coronary outflow, the activity of malonyldialdehyde (MDA) and superoxide dismutase (SOD) in myocardium were detected. And the scope of myocardial infarction and the concentrations of myocardial cAMP and PKA were also assessed. Results Compared with the I/R group, the level of MDA for the DPC group decreased significantly (8.28±2.04 nmol/mg vs. 15.52±2.18 nmol/mg, q=11.761,Plt;0.05), the level of SOD increased significantly (621.39±86.23 U/mg vs. 477.48±65.20 U/mg, q=5.598,Plt;0.05). After a 30 min reperfusion, compared with the I/R group, the content of CK decreased significantly (82.55±10.08 U/L vs. 101.64±19.24 U/L, q=5.598, Plt;0.05) and the infarct size reduced significantly (5.63%±9.23% vs.17.58%±5.76%, q=6.176,Plt;0.05) in the DPC group. The cAMP concentration in the DPC group was much higher than that in the I/R group (0.64±0.07 pmol/g vs. 0.34±0.05 pmol/g, q=14.738,Plt;0.05), and PKA concentration was also much higher than that in the I/R group ［17.13±1.57 pmol/(L·min·mg) vs. 12.85±2.01 pmol/(L·min·mg), Plt;0.05］. However, there were no significant differences between the I/R group, DMSO group and the control group in the above indexs (Pgt;0.05). Conclusion DPC significantly improves the releasing of cAMP and PKA, decreases oxygen free radicals, and relieves myocardial ischemia reperfusion injury. The cAMP signaling pathway may be involved in triggering the process of myocardial protection mechanisms of DPC.