Objective To design a novel stentless porcine aortic bioprosthesis and test the feasibility and its function in vitro after the valve was implanted by a modified method. Methods Six stentless porcine aortic bioprosthesis were divided into two groups according to different implantation, single layer suture group: new improvement stentless porcine aortic bioprosthesis sutured with single layer was implanted; double layer suture group: stentless porcine aortic bioprosthesis developmented by our laboratory used double layer suture was implanted. Each group contained three scales: 23 mm ,25 mm and 27 mm. Analogue ex vivo aortic valve replacement was performed , the feasibility of the new implantation was detected. Effective orifice area, transvalvular pressure gradient and regurgitation ratio were recorded at the cardiac output of 2.0 L/min, 3.5 L/min, 5.0 L/min and 7.0 L/min under the guideline of International Organization for tandardization （ISO）5840. Results The average aortic valve implantation time used for single layer suture and tradition double layer suture were 50 min and 70 min respectively. The transvalvular pressure gradient in the single layer suture group were significantly lower than those in double layer suture group under the flow of 5.0 L/min in 23 mm valve and 27 mm valve （13.51±0.51 mm Hg vs. 14.44±0.99 mm Hg, 7.36±0.19 mm Hg vs. 7.53±0.28 mm Hg；P＜0.01）;and the effective orifice area in the single layer suture group were larger than those in double layer suture group in the same case(1.87±0.06 cm2 vs. 1.76±0.08 cm2, 2.26±0.07 cm2 vs. 2.16±0.05 cm2；P＜0.01). There was no statistically difference in other parameters between both groups. Conclusion The novel design of new improvement stentless porcine aortic bioprosthesis used single layer suture has good hemodynamic characteristics as the nature structure . The modified suture method decrease the implantation time.Nemerical data of the evaluation in vitro show that the difference between single layer suture group and double layer suture group in effective orifice area,transvalvular pressure gradient and regurgitation ratio haveno statistical significance. This experiment is the foundation of the animal and clinical experiment in the future.
Abstract： Objective To investigate the protective effects of adenosine (ADO) on lung ischemia/reperfusion injury following heart-lung transplantation in canine. Methods Canine heart-lung transplantation was performed．Canines were divided into two groups: transplant control groupand ADO group. The changes of arterial partial pressure of oxygen(PaO2) after reperfusion in two groups at 30，60，90，120 min were observed．The tissue contents of nitric oxide (NO) were measured at 10 min before ischemia, 10 min and 120 min after ischemia; 10 min and 60 min after reperfusion．The lung tissue samples were obtained 1h after reperfusion．The tissue myeloperoxidase(MPO) activity,content of malondialdehyde(MDA), content of superoxide dismutase(SOD), wet/dry ratio of lung(W/D) were measured.Microscopic examination of lungs was also conducted. Results (1)In ADO group，PaO2 were significantly higher than that in control group at 30，60，90 and 120 min after reperfusion (Plt;0.05)．(2) The tissue contents of NO at 120 min after ischemia, 10 min and 60 min after reperfusion were significantly lower than that at 10 min before ischemia(Plt;0.05). In ADO group，the tissue contents of NO at 120 min after ischemia, 10 min and 60 min after reperfusion were higher than that in control group respectively(Plt;0.05). (3)The tissue MPO activity, content of MDA, W/D in ADO group were significantly lower than those in corresponding control group. The content of SOD in ADO group were higher than that in control group(Plt;0. 05)．(4)The microscopic examination showed that there were severe leukocyte infiltration and edema formation in the alveolar space in control group, but the changes were less severe in ADO group. Conclusion Administration of ADO in canine heart-lung transplantation can protect the donor lung against ischemia／reperfusion injury．
Objective To investigate the operative characteristic and results of the modified Fontan procedure, and improve the application of Fontan procedure in the clinic. Methods From Sep. 1992 to June 2006, 77 cases (aged 2.5 years to 20.0 years) with a wide range of complicated congenital heart diseases underwent the modified Fontan procedure.Right atriumpulmonary artery connection were performed in 21 cases, intraatrium fenestrated baffle or conduit total cavopulmonary connection were performed in 28 cases, extracardiac conduit total cavopulmonary connection were performed in 24 cases, atrium wall lateral tunnel total cavopulmonary anastomosis were performed in 2 cases, extracardiac pericardialtube total cavopulmonary anastomosis was performed in 1 case, and extracardiac direct total cavopulmonary connection was performed in 1 case. Results In early postoperative period, there were 1 case of successful reoperation and 5 death, the cause of death were heart failure (3 cases), arrhythmia (1 case) and cerebral hemorrhage (1 case). The early survival rate was 93.5%(72/77), with 92.0% free from failure. The eject fractions of left ventricle (LVEF) after operation were increased than those before operation （68.5%±4.0% vs.62.0%±4.5%,P=0.032） and left ventricular enddiastolic diameter (LVEDD) were decreased than those before operation （52.5±7.8mm vs.62.5±11.0mm, P=0.013）. A total of 63 cases (87.5%) were followed up from 1 to 15 years after operation. In late postoperative period, there were 4 cases of death, and 1 of successful re-operation. Late survival rate was 88.3%, with 86.0% free from failure. Conclusion In the treatment for complicated congenital heart diseases, the modified Fontan procedure could result in good early and longterm outcome, and the choices for surgical procedure are various.
Abstract： Objective To find out goodness and weakness by comparing totally thoracoscopic surgery （TTS）and median sternotomy （MS）with cardiopulmonary bypass for pediatric open heart operation. Methods One hundred and fortyseven patients with ventricular septal defect(VSD) and atrial septal defect(ASD) were randomly divided into two groups according to operative methods, TTS group: patients were operated by totally thoracoscopy; MS group: patients were operated by median sternotomy with cardiopulmonary bypass. The clinical records from two groups were compared on operative effect, complications, hospitalization, ventilation time,variations of main data of blood routine test, drainage of pleura cavity, blood loss and transfusion, and pulmonary function. Results There were no death in two groups. There was VSD residual leak the same day after operation which was cured by TTS in one patient of TTS group. There was one case which bleeding was stopped by second operation in MS group. Followup visit were made to 41 patients for 3 months, no heart murmur was detected. The ultrasonic cardiography (UCG) showed that correcting of VSD and ASD were good and had no residual leak. The hospitalization,aortic clampping time, ventilation time and variations of main data of blood routine test, drainage of pleura cavity, blood transfusion and blood loss in TTS group had no significant difference to those in MS group (Pgt;0.05). Operating times was longer in TTS group than that in MS group, while stays in the intensive care unit were shorter in TTS group than that in MS group (Plt;0.01). Preoperative and 3 months postoperative pulmonary function of both teams had no statistically significant difference in two groups (Pgt;0.05). Conclusion TTS is a safe and effective method to pediatric VSD and ASD as MS is.
Objective To compare the perfusion pressure between cardiopulmonary bypass (CPB) through improved intubations of femoral artery-vein and routine identical flow on organic perfusion such as brain, lung, liver, kidney, intestines, etc.. Methods Twenty dogs with body weight from 10-15kg were randomly divided into two groups: thoracoscope group(n=10): CPB was set up by the right femoral artery-vein for completely video assisted cardiac operations; routine thoracotomy group(n=10): CPB was set up by the aorta-caval vein. The perfusion pressure of innominate artery, left common carotid artery, superior mesenteric artery, renal artery, homonymic and opposite side popliteal artery and the pressure of concomitant vein were measured at the following time points: instantly after induction of anesthesia (T1) , before aortic clamping (T2) , fifteen minutes after aortic clamping (T3) , fifteen minutes after aortic opening (T4) , twenty minutes after stop (T5) . The venous blood samples were collected at the preceding time points and venous oxygen saturation (SvO2) were measured. Results There were no significant difference between both groups in arterial perfusion pressure, besides perfusion pressure of homonymic popliteal artery in thoracoscope group was lower than that in routine thoracotomy group (Plt;0. 01) . Before aortic clamping, fifteen minutes after aortic clamping and fifteen minutes after aortic opening, venous pressure of renal vein, superior mesenteric vein, homonymic and opposite side popliteal vein in thoracoscope group were higher than those in routine thoracotomy group (Plt;0. 05) . SvO2 of renal vein, superior mesenteric vein, homonymic and opposite side popliteal vein in thoracoscope group were lower than those in routine thoracotomy group (Plt;0. 05) . Conclusion The improved femoral CPB has a similar perfusion pressure with routine CPB and a higher vein pressure than routine CPB below inferior vena cava after aortic intubations. So this experiment provides theoretical evidence for the organic protection of infants’ thoracoscopic extracorporeal circulation.
Objective To introduce a new type of bileaflet mechanical prosthetic heart valve （GK bileaflet valve）and evaluate clinically the early hemodynamic effect and short term follow-up after its replacement. Methods Sixty-one patients with heart valve diseases were operated upon. The mitral valve replacement was performed in 34 patients, aortic valve replacement in 16 patients and double valve replacement in 11 patients. A total of 72 GK bileaflet mechanical valves were implanted, 45 in mitral position, and 27 in aortic position. Blood consistency and hemodynamics were monitored. Follow-up was carried out routinely to check whether there were some valve-related complications. Results There was no early mortality （〈30 d）. Only one patient died of trauma 2 months after the operation. Follow-up was 100% and extended 1 to 2. 5 years. Without valve-related complications all patients had lived for more than 1 to 2.5 years. In 98% （60/61） of survivors heart functional performance had improved to New York Heart Association class Ⅰ or Ⅱ . Conclusion Early clinical results and short term follow up demonstrate that GK bileaflet prosthetic heart valve exhibits excellent hemodynamic properties, satisfied blood consistency and a low incidence of valve-related complications. Midterm and long-term results should be observed further.