Abstract： Objective To summarize our experience and clinical outcomes of preservation of posterior leaflet and subvalvular structures in mitral valve replacement（MVR）. Methods We retrospectively analyzed the clinical data of 1 035 patients who underwent MVR in Beijing An Zhen Hospital from January 2006 to March 2011. There were 562 male patients and 473 female patients with their age of 37-78（53.84±13.13）years old. There were 712 patients with rheumatic valvular heart disease and 323 patients with degenerative valve disease, 389 patients with mitral stenosis and 646 patients with mitral regurgitation. No patient had coronary artery disease in this group. For 457 patients in non-preservation group, bothleaflets and corresponding chordal excision was performed, while for 578 patients in preservation group, posterior leafletand subvalvular structures were preserved. There was no statistical difference in demographic and preoperative clinical characteristics between the two groups. Postoperative mortality and morbidity, and left ventricular size and function were compared between the two groups. Results There was no statistical difference in postoperative mortality（2.63% vs. 1.21%, P =0.091）and morbidity （8.53% vs. 7.44%, P=0.519）between the non-preservation group and preservation group, except that the rate of left ventricular rupture of non-preservation group was significantly higher than that of preservation group（1.09% vs. 0.00%, P=0.012）. The average left ventricular end-diastolic dimension （LVEDD）measured by echocardiography 6 months after surgery decreased in both groups, but there was no statistical difference between the two groups. The average left ventricular ejection fraction (LVEF) 6 months after surgery was significantly improved compared with preoperative average LVEF in both groups. The average LVEF 6 months after surgery in patients with mitral regurgitation in the preservation group was significantly higher than that in non-preservation group （56.00%±3.47% vs. 53.00%±3.13%，P =0.000）, and there was no statistical difference in the average LVEF 6 months after surgery in patients with mitral stenosis between the two groups（57.00%±5.58% vs. 56.00%±4.79%，P =0.066）. Conclusion Preservation of posterior leaflet and subvalvular structures in MVR is a safe and effective surgical technique to reduce the risk of left ventricle rupture and improve postoperative left ventricular function．
Objective To observe the intermediate-term outcome and heart function in patients with small aortic root，and to investigate the feasi bility of small size prosthesis. Methods From July 1990 to Jun e 2003, 62 patients underwent 19mm aortic valve prosthesis(19mm group). The resu lts were compaired with other 62 patients receiving larger prosthesis(≥21 mm,21 mm group). Clinical symptoms, signs, electrocardiogram(ECG) and echocardiogr a phy (UCG) were followedup, KaplanMeier survival curve was used for analysis. Results In 19mm group, there were 38 patients with ≥Ⅱ/Ⅵ grade systolic murmur in aortic valve area,18 patients with ECG ST segm ent change and 11 patients with chest pain and/or chest distress. Postoperative cardiac function showed that 33 patients with heart function New York Heart Ass ociation(NYHA) class Ⅱ and 29 patients with NYHA class Ⅲ. Postoperative ECG sh owed in 21mm group,6 patients with ECG ST segment change,3 patients with chest distress and 6 patients with occasional chest pain and there were 48 patients with NYHA class Ⅱ and 14 patients with NYHA class Ⅲ,there was statis tically difference in heart function between two groups（P＝0.020). Th ere was a significant regression of left ventricular end diastolic diameter(LVEDD),left ventricular wall thickness, mass index,and pressure gradients in both groups（P＜0.05）, and left ventricular ejection f raction (LVEF)had a significant increase in patients 5 years after operation tha n that before operation（P＜0.05）, and there was no statistically differenc e in both groups（P＞0.05）. Actual survival at 1,5 years were 93.5%,74 .2% in 19mm group compared with 95.2%,790% in the 21mm valve group, there were no statistically difference in both groups （P=0.231,0.110）. Conc lus ion Patients with 19mm prosthetic aortic valves can experience a satisf actory improvement and get excellent intermediate-term survival.
Objective To compare chordal transposition and chordal shortening in repairing anterior leaflet prolapse (ALP)， and explore the surgical indications as well as merits and demerits of these two techniques. 〖WTHZ〗Methods We retrospectively reviewed the data of 90 ALP patients recruited into Anzhen Hospital between March 1986 and March 2008, and classified them into chordal shortening group (n=23) and chordal transposition group (n=67). KaplanMeier survival curve and freedom from reoperation curve were established to compare the two groups. Univariate analysis and multivariate logistic analysis regression were used to identify independent risk factors for early death and late cardiac events. 〖WTHZ〗Results There were three perioperative deaths in chordal shortening group（13.0%）, and three deaths in chordal transposition group (4.4%), and the difference was not significant (χ2=2.019，P=0.155). The follow-up time ranged from 1 month to 18 yrs（7.70±5.41 yrs）. There were 5 late deaths, of which 3 were in chordal shortening group and 2 in chordal transposition group. The KaplanMeier survival curve showed that 5-year survival rate of chordal shortening group was significantly lower than chordal transposition group (70.00%±18.24% vs.98.00%±1.98%,χ2=12.50, P=0.000); And the KaplanMeier freedom from reoperation curve showed [CM(159mm]that 5-year reoperation rate of chordal shortening group was also significantly lower than chordal transposition group (83.30%±15.20% vs.96.10%±2.71%,χ2=10.27，P≤0.001). By the univariate analysis, we found that age＞55 yrs old, concomitant CABG procedure, New York Heart Association (NYHA) function class Ⅲ-Ⅳ, preoperative heart failure history, aortic clamping time＞90 min, and preoperative lefe ventricular ejection fraction (LVEF)＜45% were the risk factors for perioperative death and risk factors for late cardiac events included postoperative mitral regurgitation＞2+, chordal shortening technique, preoperative heart failure history, and aortic clamping time＞90 min. The multivariate logistic analysis regression showed that aortic clamping time＞90 min, concomitant CABG procedure, preoperative LVEF＜45% were the independent predictors for perioperative death, and NYHA class ⅢⅣ, chordalshortening technique and residual mitral regurgitation＞2+ were the independent predictors for the late cardiac events. Conclusion （1） There is no statistically difference between chordal transposition and chordal shortening in the perioperative survival rate. (2) Chordal transposition has a relative superiority to chordal shortening in terms of 5-year survival rate. (3) Chordal transposition has a higher mid and longterm rate of freedom from reoperation than chordal shortening. （4） Although chordal transposition has a lower incidence of reoperation and ahigher mid and longterm survival rate, the indication for it is restricted to less extensive ALP and patients with transferrable chord in the posterior leaflet. Chordal shortening is an independent risk factor for late events.
Objective To evaluate the early and middlelongterm clinical results of tricuspid valve replacement (TVR) and compare the relative merit between bioprothesis and mechanical valve in tricuspid position，so as to elevate the operative effect. Methods The data of 128 TVR from April 1992 to February 2008 in An Zhen Hospital were retrospectively reviewed， and classified into mechanical prosthesis group（n=89）and bioprothesis group（n=39）according to the prosthesis used in the first procedure. Kaplan-Meier curve were estimated to evaluate the midlong term survival rate and events incidence related to prosthesis（including thrombosis, embolism and bleeding related to prosthesis and the prosthesis deterioration）. Multivariate binary logistic regressions were used to evaluate the independent risk factor for early and late death. Results There were 19 early deaths( 14.84%). With the followup of 4.93±2.92 years, there were 11 late deaths(10.7%). According to the Kaplan-Meier curve, the 10year actuarial survival rate for the bioprothesis group and mechanical prosthesis group were 65.6%±17.4% and 68.7%±10.8% respectively(Log-rank test,χ2=0.74，P=0.390). Freedom from prosthesis-related embolism at 5 years for the bioprothesis group and mechanical prosthesis group were 92.3%±7.4% and 87.1%±4.6% respectively(Log-rank test, χ2=0.962，P=0.327). Freedom from anticoagulationrelated bleeding at 10 years for the bioprothesis group and mechanical prosthesis group were 100% and 79.7%±9.7% respectively(Log-rank test, χ2=1.483，P= 0.223). There were 9 TVR reoperation, freedom from reoperation at 7 years for the bioprothesis group was 71.1%±18.0%, and freedom from reoperation at 10 years for the mechanical prosthesis group was 78.8%±10.2% (Log-rank test, χ2=2.76，P=0.096). Binary logistic regression revealed that the redo procedure and ascites were independent risk factors for early death, whereas ascites, heart function of New York Heart Association class Ⅲ/Ⅳ and multi valve replacement were independent risk factors for late death.Conclusion To lower the operative mortality and late mortality and morbidity, TVR should be adopted prior to the deterioration of right heart function, and bioprothesis valve has similar early and middlelong term clinical effect with mechanical valve in tricuspid position.
ObjectiveTo study the external biocompatibility bewteen the mouse induced pluripotent stem cells (miPSCs) and poly-3-hydroxybutyrate-co-3-hydroxyhexanoate (PHBHHx). MethodsAfter we recovered and subcultured miPSCs, we divided them into two groups. There was one group cultured with material of PHBHHx films outside the body. We observed the adhesive pattern of miPSCs on film by fluorescence of 4, 6-diamidino-2-phenylindole (DAPI) staining. The cell vitality was detected by cell counting kit-8 (CCK-8). The morphology of miPSCs attached on the film was visualized under scanning electron microscope (SEM). We used the traditional petri dish to culture miPSCs and detect the cell activity by CCK-8. ResultsMiPSCs can adhere and proliferate on PHBHHx films. The result of cell vitality which detected by CCK-8 showed that there was a statistical difference in OD value between culturing on PHBHHx films and traditional cultivation (0.617±0.019 vs. 0.312±0.004, P < 0.05). ConclusionThere are adhesion and proliferation on the surface of cells patch made by miPSCs co-culturing with PHBHHx film. Compared with traditional culturing in the cell culture dish, culturing in PHBHHx films have great advantages in the process of adhesion and proliferation. PHBHHx can be used as one of the scaffold for stem cells treating various disease.
ObjectiveTo investigate the feasibility of small molecule compound XAV939 to induce mouse embryonic stem cells (mESC) to differentiate into cardiac myocytes. MethodsWe revived and cultured undifferentiated mESC growing confluently on trophoderm made of mouse embryonic inoblast cell. The mESCs were digested by trypsin to form embryoid bodies (EBs) by handing drop method. After plated, EBs were induced by XAV939 to differentiate into cardiac myocytes. We observed the cardiac myocytes with lightmicroscopy and identified it with immunofluorescence method. Result The XAV939 can effectively induce mESC into cardiac myocytes with the mean efficiency rate of 71.85%±1.05%. The differentiated cardiac myocytes shrinked spanteously and rhythmicly. The cardiac troponin T as the special marker of cardiac myocyte was positive. ConclusionThe small molecule compound XAV939 could effectively induce mES cells into cardiac myocytes.