1mm内径涤纶小血管桥接大鼠颈总动脉的实验研究

Small diameter Vascular Prosthesis for Bridging Carotid Artery

采用４８只ＳＤ雄性大鼠，切除７ｍｍ一段左颈总动脉，以１０ｍｍ长、１．０ｍｍ内径的涤纶小血管桥接之．术后２４、７２小时及１、２、３、４、８和１２周分别以多普勒超声监测血流通畅情况．每次随访时，对５例通畅者（８周时３例，１２周时４例）及所有不通畅者行手术探查或血管造影检查，以进一步证实多普勒检查结果的正确性，同时取下桥接血管．部分桥接血管经处理后作扫描电镜检查．结果显示桥接后１２周的累积通畅率为７７．１％．快速而完全的内皮化过程在桥接后３周即完成，形成一光滑的内皮细胞层．１１例桥接血管因血栓形成而失败，其中１０例发生在桥接后３周之内，即内皮化之前．提示涤纶小血管可成功地用于大鼠颈总动脉桥接，失败主要发生在内皮化之前，其原因为血栓形成，若用抗凝药物或内皮细胞种植防止早期血栓形成，可望进一步提高通畅率，有可能使其成功地用于临床．

The implantation of microvascular dacron grafts (MDG) (internal diameter=1mm,length=10mm) in carotid arteries was studied in 48 Sprague Dawley rats.The left carotid artery was resected 7mm in length and replaced with MDGs by means of sleeve anastomosis.Postoperatively,the patency was monitored with Doppler ultrasound at 24 and 72 hours,and 1,2,3,4,8 and 12 weeks respectively and confirmed either by direct inspection intraoperatively or by angiography at time of removal.At each time,all the thrombosed and some selected patent grafts were removed and prepared for scanning electron microscopic study.The early patency rate was 100 percent within 24 hours and the cumulative long term patency rate was 77.1 percent in 12 weeks.Rapid and complete endothelial lining was demonstrated in three weeks which provided a smooth and nonthrombogenic surface,and contributed to the patency.Ten of the 11 failed grafts occurred within three weeks due to thrombosis before endothelial lining.These observations indicate that MDGs can be successfully used as arterial conduits in rats and suggest that an enhanced patency may be expected with the use of platelet inhibitor or endothelial seeding for the prevention of early thrombosis.(Original article on page 198)