Abstract:Since 1978 the definition of prosthesis-patient mismatch（PPM） was first introduced by Rahimtoola, it has attracted the attention of foreign researchers. The PPM phenomenon is concerned to be an important factor which will affect patients＇ survival rate and quality of life. Till now, a lot of effort should still be put on this problem. But unfortunately, this problem is still being neglected in our country. This paper is a review of PPM from it＇s many aspects, such as definition, current research status, prevention, and it＇s research prospect. We hope this paper will intensify the clinicians＇ knowledge on PPM.
Technical advances both in cardiac surgery and relating to anesthesia,cardiopulmonary bypass and myocardial protection have significantly improved the prognosis for patients combined with coronary heart disease and heart valve disease. In addition to technology, variable factors that affect operative survival following combined operation include the severity of valvular disease, the number of coronary vessels affected, impairment of left ventricular function and both age and gender differences. In this article, we review the outcome of surgical intervention for heart valve disease combined with coronary heart disease and discuss future prospects in this field.
Objective To summarize the early outcomes and clinical experience in the use of skeletonized internal mammary artery(IMA) for coronary artery bypass grafting(CABG). Methods From January 2004 to June 2007, a total of 139 patients underwent CABG and received skeletonized arteries in this hospital. Results The number of distal anastomoses was 3.6±1.7,there was no sternal wound infection or thoracic cavity effusion. Two patients died (1.4%), the complications incidence was 5.8%(8/139) lung infections 3 cases, incision infections 2 cases, and low cardiac output syndrome 3 cases.All complications were well treated by using antibiotics, dressing change and positive inotrope, and the follow-up period was 2 to 34 months(20.6±5.9 months); 110 patients were followed up (80.3%). All living patients were free from angina after operation and showed I-II class heart function (New York Heart Association). Conclusion Using skeletonized IMA is? a safe and effective method in CABG.
Objective To observe the expression of integrin αVβ3 in vascular endothelium cultured in vitro at different time points under different level of shear stress. Methods（1）We established a vascular culture system in vitro which could provide steady flow with different level of shear stress, and tested the flow stability when loading different level of shear stress. （2） A total of 50 rabbits were randomly divided into low shear stress group （5 dyn/cm2, n=25）and normal shear stress group（20 dyn/cm2, n=25）. Rabbits in each group were further randomly divided into five different time points as 2 h, 4 h, 8 h, 16 h and 24 h（n=5 at each time point）. The descending aorta of rabbits were harvested and cultured in the vascular culture system in vitro under different level of shear stress. The expression sites and intensity of αVβ3-Integrin in vascular endothelium were examined at 5 different time points in both groups by immunohistochemical staining. Results The vascular culture system in vitro was stable in providing laminar flow with different level of shear stress required for the experiment. Vascular endothelium expressions of αVβ3-Integrin in the low shear stress group were in high level at all the 5 time points and reached its summit at 16 h, when the mean optical density（MOD）value was （1.995±0.194）×10-2. In the normal shear stress group, the MOD value decreased time-dependently at the 5 time points. The MOD values at 2 h （0.059±0.005）×10-2 and 4 h（0. 049±0.002）×10-2 were significantly higher than those at other time points （P＜ 0.05）. The αVβ3-Integrin MOD values of the low shear stress group were significantly higher than those of the normal shear stress group at all the 5 respective time points （P=0.000）. Conclusion Low shear stress can significantly promote the expression of αVβ3-Integrin while normal shear stress decreases the expression of αVβ3-Integrin in vascular endothelium cultured in vitro.
Objective To modify the method for aortic end strengthening in acute type A aortic dissection operation, and investigate its clinical efficacy. Methods We modified the method for aortic end strengthening in acute aortic dissection operation based on ‘Sandwich method’ in the department of thoracic and cardiovascular surgery of West China Hospital. From January 2006 to December 2008, twentyeight patients with acute type A aortic dissection underwent modified aortic end strengthening operation. We made adventitia turn over and enfold to strengthen the aortic end in 10 cases, and placed stripshaped felt or pericardium belts between dissection (between adventitia and intima)and inner intima and strengthened the aortic end by suture in 18 cases. The hemorrhage of anastomotic stoma and the postoperative early prognosis were observed. Results No bleeding complication was found in all the cases. Two cases died, one died of severe low cardiac output syndrome and another died of multiple organ failure. No nervous system complication was found except that 2 cases had delayed revival. No sternum and surgical incision related complication was found. The rest 26 cases were cured and discharged. Conclusion The modified method for aortic end strengthening can not only strengthen the aortic end but also make people be able to find the petechia of anastomotic stoma clearly, then stitch hemostasia could be done effectively. The method is easy to implement and effective, it should be extend in clinic.
Objective To evaluate the effectiveness of unsupported reduction ascending aortoplasty for dilatation of the ascending aorta. Methods Between September 2005 and May 2011, 53 patients with aortic valve disease and dilatation of the ascending aorta underwent aortic valve replacement with unsupported reduction ascending aortoplasty. There were 41males and 12 females, aged 22-75 years (mean, 52 years). The disease duration was 1 month to 14 years. The color Doppler echocardiography showed that the diameter of the ascending aorta before surgery was (45.9 ± 3.3) mm; bicuspid aortic valve and tri-aortic valve were observed in 13 and 40 cases respectively. The heart functions were graded as II level in 19 cases, III level in 33 cases, and IV level in 1 case according to the standard of New York Heart Disease Academy (NYHA). Results After operation, mediastinum errhysis occurred in 1 case, pneumonia in 3 cases, and III degree atrioventricular block in 1 case. There was no related complication of the aortoplasty. All the patients were followed up 3-68 months (mean, 15 months), and had no obvious chest tightness and palpitation. At last follow-up, the NYHA heart functions were graded as I level in 22 cases, II level in 31 cases; the diameter of the ascending aorta was (35.2 ± 4.0) mm, showing significant difference when compared with the preoperative one (P=0.000), but no significant difference when compared with the one at discharge (34.0 ± 2.5) mm (P=0.245). There was significant difference in the diameter of the ascending aorta between last follow-up and preoperation, at discharge in the patients who were followed up more than 60 months (P lt; 0.05); significant difference was found between last followup and preoperation in patients with bicuspid aortic valve (P lt; 0.05), but no significant difference between last follow-up and preoperation (P gt; 0.05) in patients whose diameter of the ascending aorta was more than 50 mm before operation. Conclusion Unsupported reduction ascending aortoplasty has good short- and mid-term results in treating aortic valve disease with mild to moderate dilatation (diameter range, 40-50 mm) of the ascending aorta. Inclusion criteria of the aortoplasty should be strict. Long-term results need further follow-up.