A Clinical Analysis of Thirty-Five Patients Undergoing Aortic Reoperation

Abstract Introduction: At present, there are few reports regarding the issue of aortic reoperation due to its complexity and high risk and individual differences among patients. Methods: From November 2016 to December 2017, the data from 35 cases of aortic reoperation at our institution, out of 212 consecutive aortic repairs, were reviewed. We retrospectively summarized and analyzed their surgical indications, operative data, time interval from previous aortic repair, and outcomes. The time intervals until reoperation were analyzed for differences. Results: Patients' mean age was 40.9±14.5 years, and 25 of them were men (71.4%). The indications for reoperation were aortic valvular problem (14.3%), aneurysmal dilatation (25.7%), pseudoaneurysm formation due to anastomotic leakage (43.2%), and aortic dissection (17.1%). For patients who had underwent primarily emergency operations due to aortic dissection, the time interval until reoperation (4.8±3.2 years) was significantly shorter than that of the whole group (5.5±3.6 years, P<0.01). Among the 35 reoperations, Sun's procedure was selected for 16 patients (45.7%) with total aortic arch reconstruction. The average follow-up was 12 months (range 9-15 months). Hospital mortality was 5.7% (two patients). Among the hospital survivors there were no cases of death, rupture of residual dissection, paraplegia, or central nervous system complications during the follow-up period. Conclusion: Patients with acute aortic dissection required repeat surgery significantly earlier compared to other diseases. As to reoperation strategy, we recommend Sun's procedure as the choice for extended arch reconstruction since minimal effect on overall mortality and complication rates were found.

The simulation of multiphase flow field in ventricular assist device and analysis of hemolytic capability / 中华胸心血管外科杂志

Objective:The hemolytic prediction model of the axial flow impeller blood pump is carried out by using a computational fluid dynamics(CFD) multiphase flow model.Methods:The hydrodynamic performance of the pump and the flow field in the pump, and the shear stress distribution are analyzed. A hemolytic prediction model based on the shear stress is built based on the calculation results. Hemolysis tests in vitro were performed 6 times with fresh bovine blood. At each time, the flow of the ventricular assist device(VAD) is 5 L/min and the outflow tract pressure is 100 mmHg(13.3kPa). According to the tests, the plasma free hemoglobin(FHB) content and the hematocrit(HCT) are measured every half hour. At the end of each experiment Normal Index of Hemolysis(NIH) is calculated.Results:The average of NIH is 0.0055 g/100L, almost identical with that obtained from the hemolytic prediction model.Conclusion:Multiphase flow model can be used for quantitative predictions of the hemolytic behavior of a VAD. This method can be applied in the selection stage of a blood pump.

Dual-source CT in the diagnosis of tetralogy of Fallot / 中华胸心血管外科杂志

Objective To investegate the value of dual-source CT (DsCT) in the diagnosis of tetralogy of Fallot (TOF).Methods The measurement results of the main pulmonary artery( PA),left pulmonary artery (LPA),right pulmonary artery( RPA ),right entricular outflow tract(ROVT) of 42 cases with TOF by DsCT,echocardiography aud surgery were ret rospectively analyzed.Results Of the 42 cases,a total of 232 cardiac nomalies were found by surgery ( 145 intra cardiac anomalies,53 ventricular-aterial connection anomalies,34 external cardiac anomalies),DsCT and echocardiography found 204 cardiac nomalies (130 intra cardiac anomalies,12 ventricular-aterial connection anomalies,53 external cardiac anomalies),224 cardiac nomalies ( 145 intra cardiac anomalies,31 ventricular-aterial connection anomalies,48 external cardiac anomalies)respectively;and the diagnostic accuracy of DsCT and echocardiography was 88％ (204/232),97％ (224/232) respectively.There was not significant difference between DsCT and surgery ( P ＞ 0.05 ).There was significant difference between echocardiography and surgery in PA,LPA and RPA (P＜0.05),but not in ROVT and over-riding of the aorta (P＞0.05).There was not significant difference between DsCT and echocardiography ( P ＞ 0.05 ).Conclusion Echocardiography was superior to DsCT in intra cardiac anomalies,especially in the cardiac septal defects and heart valve diseases.DsCT had the advantages in external cardiac anomalies,particularly in assessing pulmonary artery.

The experimental study of the the muscarinic receptor path way on ischemia reperfusion injury in aged myocardium / 中华胸心血管外科杂志

Objective By using cardiac ischemia reperfusion model, the muscarinic receptor path way of cardiac signal conduction in both young and aged myocardium was studied. The aim was to study the pathogenesis of ischemia reperfusion injury in aged myocardium. Methods 20 dogs (15～20 kg) were randomly divided into two groups: group A (young, 3～4 years old, n=10), group B (old, 7～8 years old, n=10). All dogs underwent 60 minutes of global ischemia and 30 minutes of reperfusion under cardiopulmonary bypass (CPB). A tunnel was inserted through the left ventricular apex, to measure the LVEDP、+dp/dt、-dp/dt and ECG. . Myocardial specimens were collected at the beginning of reperfusion, 30 min after reperfusion and 60 min after reperfusion. Myocardium was prepared or studied of density of muscarinic receptor, G protein level, cGMP, guanylate cyclase activity, value of NO, protein level of eNOS, mRNA level of iNOS and eNOS. Results (1) Group B had higher LVEDP but lower +dp/dt max and -dp/dt max than group A in each stage. After CPB, the LVEDP showed no difference between pre and post surgery in two groups, while +dp/dt max and -dp/dt max were decreased in both groups, more significantly in group B. (2) At 30 min and 60 min after reperfusion, the density of M receptor was significantly increased in group B than that in group A. (3) There was no significant difference in Gs pre and post surgery in group A. Compared with group B, the level of Gi decreased significantly after the reperfusion in group A. There were decreasing in Gs and Gi after reperfusion in group B, more greater in the former. The ratio of Gi/Gs in group B was much higher than that in group A. (4) Compared with group A, the mRNA level of eNOS and protein level of eNOS decreased more significantly in group B during each stage of reperfusion. After ischemia reperfusion, the mRNA level of iNOS, NO, cGMP and guanylate cyclase activity were obviously increased in group B than that in group A.Conclusion (1) After the cardiac surgery in elder model, the M receptor path way increased significantly, which is negatively correlated with cardiac function, hence promote the ischemia reperfusion injury in elder myocardium. (2) In the ischemia reperfusion injury in elder myocardium, higher vagotonic does more harm to the old myocardium through NO and NO cGMP pathway.