| Objective:To explore the influence factors and the improvement methods of valvular function of bovine jugular vein conduit(BJVC), and to provide a basis for material selection of BJVC.Methods:Using self-made pressure control system simulate pulmonary blood flow, measuring BJVC diameter and reflux in30seconds under different perfusion levels, calculating the inflation rate and reflux rate, evaluating the degree of reflux. Stress condition is set to six conditions:10mmHg,20mmHg,30mmHg,40mmHg,50mmHg and analog arteriopalmus, the high pressure is controlled at40mmHg and the low pressure is controlled at10mmHg when analog arteriopalmus, to make it as close as the normal pulmonary artery pressure of human beings. Comparing the dilation and the reflux of BJVC with different wall thickness and valve sinus height under pressure, explore the influence of anti-reflux function of BJVC caused by wall thickness and valve sinus height. Designing and installing pulmonary valve annulus restraining device, compare the dilation degree and the reflux of BJVC difference before and after the installation of pulmonary valve annulus restraining device, exploring the influence of the anti-reflux function of BJVC caused by the device.SPSS19.0statistical software is used for statistical analysis of all the data.Results:The diameter, and reflux of BJVC under pressure increased with the increasing of pressure in each group. According to the wall thickness BJVC can be divided into three groups:A,0.40-0.60mm; B,0.60-0.80mm;C,0.80-1.00mm.Group A’s dilation is most obvious, the dilation rate reached18.89%in10mmHg, and group C’s dilation degree is the slightest, only19.89%in50mmHg pressure. About the reflux, group A has the most reflux volume, group B second, and group C the least, Group A and B’s reflux rates are more than5%in10mmHg when the group C’s reflux rate is more than5%under the pressure above40mmHg.The BJVC with wall thickness above0.80mm can better adapt to the low pressure environment of right heart and giving play to their anti-reflux function, and the anti-reflux function of BJVC with wall thickness under0.80mm are poor.According to the height of valve sinus BJVC can be divided into three groups:A,0.8cm;B,0.9cm;C,1.0cm.Valve sinus height of BJVC has no effect on conduit dilation, the diameter under pressure of each group has no statistical significance. Group A has the most reflux volume, group B the second, and group C the least, the reflux rates of group A and B exceed5%in pressure conditions more than20mmHg, group C’s reflux rate begins to exceed5%in30mmHg pressure; the reflux rate of group A exceeds30%in50mmHg condition, the reflux rate of group B exceeds20%in50mmHg, and the reflux rate of group C is less than10%in50mmHg condition.pulmonary valve annulus restraining device can only restrict the dilation of the part near the valve annulus, there’s no that effect of the other part of BJVC. The reflux of the group with pulmonary valve annulus restraining device (group B) within30seconds is significantly below the group without pulmonary valve annulus restraining device (group A),and the reflux rate of group A exceeds5%in10mmHg, group B’s reflux volume is less than3%in each pressure condition. Comparing the reflux volume of BJVC with different wall thickness and valve sinus height before and after the installation of pulmonary valve annulus restraining device, we found that the device’s function of anti-reflux rarely effect by the anatomical features of BJVC.Conclusion:1, The anti-reflux function of BJVC is related to wall thickness and valve sinus height, BJVCs with thicker pipe walls or bigger valve sinus have better anti-reflux function.2, Pulmonary valve annulus restraining device can effectively reduce BJVC reflux, and this effect is rarely affected by the anatomical features of BJVC... |
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