Objective To review the current status and problems in developing cardiac biological pacemaker(CBP) by cell transplantation. Methods The l iterature over the past decade concerning CBP constructed through celltransplantation was reviewed and summarized. Results Experiments in vivo testified that the cell transplantation was feasible for CBP construction, and the transplantation of sinus atrial node cell and stem cell was still the predominant method for constructing CBP. However, such problems as difficult ampl ification of transferred cardio muscle cell, low success rate of CBP construction as well as unstable function of CBP make it lag behind the tremendous cl inical demands. The gene transfection technology might be one of the approaches to resolve these issues. Conclusion As one feasible method for CBP construction, the cell transplantation has a bright future in the cl inical appl ication and is worthy of further study.
ObjectiveTo investigate clinical outcomes and safety of minimally invasive left atrial myxoma (LAM) resection via right anterolateral minithoracotomy (ALMT). MethodsClinical data of 9 patients who underwent minimally invasive LAM resection via right ALMT in the Affiliated Hospital of Luzhou Medical College from January 2011 to October 2013 were retrospectively analyzed. There were 2 male and 7 female patients with their age of 37-62 (51±9) years. The operation was performed through a small (4-6 cm) right ALMT incision. Femoral artery and vein and superior vein were cannulated to establish cardiopulmonary bypass (CPB). Transthoracic clamp was used for ascending aortic clamping. Antegrade cold blood cardioplegia was infused for myocardial protection. LAM was resected through right atriotomy trans-septal approach. ResultsAll the operations were successfully performed without in-hospital death. Operation time was 210-310(260±33) minutes, aortic cross-clamping time was 23-50(37±9) minutes, CPB time was 60-87(71±9) minutes, postoperative mechanical ventilation time was 6-14(9.0±2.5) hours, and length of ICU stay was 17-26(20±3) hours. Postoperative mediastinum drainage was 100-650(376±190) ml. Mean length of right ALMT was 4.5-6.0 (5.3±0.6) cm. All the patients were followed up for 1 to 30 months,and echocardiography showed no LAM recurrence. ConclusionMinimally invasive LAM resection via right ALMT is safe and feasible with satisfactory clinical outcomes.
ObjectiveBy comparing the difference between different stenosed degree of aortic valve in flow field uniformity and turbulent shear stress (TSS), to explore the relation between flow field uniformity and different stenosed degree of aortic valve, and probe the clinical value for deciding the operation timing, and analyze the possible role of TSS in the progress of the disease.MethodsThe flow field uniformity values and TSS in parasternal long axis plane and apical five cavity plane on each point were measured and calculated by pulse wave Doppler echocardiography technique for 33 patients with different stenosed degree of aortic valve.ResultsThere were significant difference between the different stenosed degree of aortic valve in maximal velocity difference(ΔV max )and TSS( P lt;0.05, 0.01). The more severe the aortic stenosis was, the worse the flow field uniformity was, the lower the TSS was.ConclusionsThere are significant difference between the patients of different stenosed degree of aortic valve in flow field uniformity. Flow field uniformity has important value in classifying the degree of aortic stenosis and deciding the timing of operation. The more severe the aortic stenosis is ,the lower TSS is. It can be thought that low TSS distribution has important role in pathological process of constriction in cardiovascular system diseases.
【Abstract】 Objective To investigate the expression of connexin 40 (Cx40) and hyperpolarization-activated cycl icnucleotide-gated cation channel 4 (HCN4) in rat bone marrow mesenchymal stem cells (BMSCs) cocultured with the sinoatrialnode (SAN) tissues in vitro, so as to evaluate the possibil ity of BMSCs differentiation into SAN cells. Methods BMSCs wereisolated from Sprague Dawley rats (aged 4-6 weeks, male or female) by the adhesive method and cultured; BMSCs at the 3rdpassage were marked with carboxyfluorescein succinimidyl ester, and then were incubated on 6-well culture plate; cell climingsl ices were prepared at the same time. SAN tissue was taken and cut into 0.3 cm × 0.3 cm mass, and then placed into 4℃ PBSsolution. The SAN tissue mass was cocultured with marked BMSCs at the 3rd passage for 3 weeks as the experimental group, andBMSCs at 3rd passage were cultured alone for 1 week as the control group. At 1, 2, and 3 weeks after coculture, the mean integratedabsorbance (MIA) values of Cx40 and HCN4 were measured by Image pro plus 5.0 through the method of immunohistochemistry,and the mRNA expressions of Cx40 and HCN4 were identified by real-time fluorescent quantitative PCR. Results TheMIA values of Cx40 and HCN4 in the experimental group were higher than that in the control group, showing significantdifferences (P lt; 0.01). In the experimental group, the expressions of Cx40 and HCN4 increased gradually with time. The longerthe culture time was, the higher the expressions of Cx40 and HCN4 were, showing significant differences (P lt; 0.05). The mRNAexpressions of Cx40 and HCN4 in the experimental group were significantly higher than those in the control group (P lt; 0.01); inthe experimental group, the mRNA expressions of Cx40 and HCN4 increased gradually with time, showing significant differencesbetween different time points (P lt; 0.05). Conclusion The expressions of Cx40 and HCN4 increase obviously after coculturingBMSCs with SAN tissue, indicating that BMSCs could differentiate into SAN cells by coculturing with SAN tissue in vitro.
ObjectiveTo analyze clinical outcomes of mitral valvuloplasty (MVP) via right anterolateral minithoracotomy. MethodsClinical data of 23 patients with valvular heart disease who underwent minimally invasive MVP via right anterolateral minithoracotomy from January 2011 to February 2013 in the Department of Cardiothoracic Surgery in our hospital were retrospectively analyzed. There were 8 males and 15 females with mean age of 41±10 years. The procedure was performed through a small (4-6 cm) incision via right anterolateral minithoracotomy. Cardiopulmonary bypass (CPB) was established via femoral artery and vein cannulation. Transthoracic clamp was used for ascending aortic clamping. Cold blood cardioplegia was delivered after aortic cross-clamping. Left atrial drainage was established through right superior pulmonary vein. MVP was performed through the atrial septal approach,and tricuspid valvuloplasty was performed for tricuspid regurgitation if necessary. ResultsAll the operations were successfully performed without in-hospital death. Operation duration was 160-290 (229±37) minutes. Aortic cross-clamping time was 40-121 (67±19) minutes. CPB duration was 60-136 (87±21) minutes. Postoperative mechanical ventilation time was 6-47 (16±11) hours. The length of intensive care unit stay was 19-60 (30±12) hours. Postoperative chest drainage was 80-780 (320±184) ml. Postoperative color Doppler echocardiography showed that left ventricular ejection fraction was 49%-65% (56.0%±4.8%). There were 5 patients with trivial mitrial valve regurgitation and 6 patients with mild tricuspid valve regurgitation. Postoperative mean length of the right thoracic incision was 3.9-6.0 (5.3±0.7) cm. The patients were followed up for 1-24 months. The result of echocardiography showed no modern to severe valve regurgitation. ConclusionMinimally invasive MVP via right anterolateral minithoracotomy is safe and feasible with satisfactory cosmetic and clinical results.
Objective Through analyzing BKCa channel expression in atrial fibroblasts in patients with sinus rhythm and atrial fibrillation (AF), to explore the mechanism of myocardial fibrosis and provide new therapeutic strategies for the treatment and reversal of AF structure reconstruction. Methods We selected 10 patients of rheumatic heart valvular disease who underwent valve replacement surgery. They were 5 patients with sinus rhythm (a sinus rhythm group, 2 males and 3 females with an average age of 49.1±8.3 years) and 5 with AF (an AF group, 3 males and 2 females with an average age of 50.3±5.8 years). About 100 mg tissue was obtained from the right auricula dextra, and the atrial fibroblasts were cultured by tissue block adherence method, and the expression of BKCa channel genes and proteins in cultured fibroblasts was detected by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting methods. Results (1) The general data of 10 patients between the AF group and the sinus rhythm group were compared. There was no significant difference between the two groups in age (t=1.21, P=0.67) and sex (t=2.56, P=0.75). There was statistical difference in the left atrial diameter and the right atrium diameter between the two groups (t=19.45, P=0.01; t=23.52, P=0.06); (2) the mRNA expression of BKCa subunit was detected by qRT-PCR method, and there was no significant difference in the mRNA expression of BKCa α and BKCa β1 between the two groups (t=3.14, P=0.79; t=2.88, P=0.69); (3) the expression of BKCa protein was detected by western blotting method, and there was no significant difference in the protein expression of BKCa α and BKCa β1 between the two groups (t=0.55, P=0.31; t=0.73, P=0.46). Conclusion BKCa pathway may not be involved in the pathogenesis and maintenance of AF, but it may play an important role in the process of myocardial fibrosis.
ObjectiveThrough comparing the efficacy of levosimendan with dopamine for severe valvular disease patients with atrial fibrillation surgery to explore the efficacy and safety of levosimendan used in cardiac surgery. MethodsWe allocated 48 severe valvular disease patients with atrial fibrillation surgery into a dopamine group (24 patients with 15 males and 9 females at age of 55.0 ± 17.4 years) and a levosimendan group (24 patients with 18 males and 6 females at age of 52.3 ± 16.2 years) by random digital table in the Affiliated Hospital of Luzhou Medical College between February and June 2014. The effects of the two groups were compared. ResultsHospitalization time (18.7±8.6 d vs 20.6±7.5 d, t=11.52, P=0.02) and the incidence of acute kidney injury(1/24 vs 5/24, χ2=25.30, P=0.01) in the levosimendan group were lower than those in the dopamine group. There was no statistical difference between the two groups in other early clinical outcomes. At each postoperative time point, there was no statistical difference in creatine kinase isoenzyme (CK-MB) between the two groups. While 6 to 48 hours after operation, there were significant differences in cardiac troponin (cTnI) and brain natriuretic peptide(BNP) level between the two groups (P < 0.05). Five days after operation, the left ventricular ejection fraction(LVEF) in the levosimendan group was higher than that in the dopamine group with statistical difference. ConclusionLevosimendan used for severe valvular disease with atrial fibrillation surgery is safe and effective, and has certain myocardial protection and renal protection effect, while its mechanism still needs further study.