导管直接溶栓治疗犬股静脉急性深静脉血栓后静脉壁形态学的变化

Experiment Study of Catheter-directed Thrombolysis in a Model of Acute Deep Vein Thrombosis

目的 比较导管直接溶栓 (catheter -directedthrombolysis,CDT)和系统性溶栓 (systemicthrombolysis ,ST)治疗急性深静脉血栓形成后的静脉壁形态学变化及近期疗效。方法 2 0只成年杂种犬通过结扎双侧股静脉远近端制作急性深静脉血栓模型。 4 8h后松开结扎线 ,DSA造影证实血栓形成。将模型犬随机分成CDT组 10只和ST组 10只。CDT组经股静脉插入多个侧孔的溶栓导管 ,经导管用微泵以 8ml/h的速度滴入重组链激酶 (re combinantstreptokinase ,r sk) (15 0 0 0U/kg ,溶于 5 0mlNS中 )每 2h取血测定PT、APTT ,并造影观察溶栓进展。ST组从膝下外周静脉滴入r sk用量同前。结束后造影观察溶栓效果。术后 1d从各组随机抽取 5只获取标本 ,余下的 4周后再次造影观察静脉通畅度 ,并获取标本。HE染色观察静脉是否通畅 ,是否有附壁血栓 ;Masson三色染色观察胶原纤维沉积情况 ;免疫组化染色观察平滑肌肌动蛋白表达情况 ;扫描电镜观察内皮细胞损伤程度。结果 CDT组在 6h内均能完全溶解血栓 ,血栓溶解率为 10 0 % ,而ST组仅为 2 0 % ,二者相比 ,有显著性差异 (P <0 .0 5 ) ;PT、APTT未见明显延长 ;CDT组 1d和 4周时均未见附壁血栓 ,而ST组可见有附壁血栓 ;术后

Objective To evaluate the effects of Catheter-directed Thrombolysis(CDT) and Systemic Thrombolysis(ST) on morphological changes of vein wall and late sequelae after acute Deep Vein Thrombosis(DVT). Methods DVT was produced bilaterally in mongrel dogs by proximal and distal femoral vein ligation.After 48 hours,the ligatures were removed,thrombosis was confirmed by DSA.Twenty model dogs were randomly divided into 2 groups: the CDT group (n=10) and ST group (n=10).In the CDT group,thrombosis was treated with catheter-directed recombinant Streptokinase(r-sk) infusion(8ml/h,15000u/kg on 50ml GS).Every 2 hours blood was obtained for determiniog PT、APTT,the progress of thrombolysis was determined by DSA.In the ST group,the same dose r-sk was injected through peripheral vein.At the first day,five samples were obtained in two groups.The rest were obtained at the 4th week.HE stain was used to assess the patency of vein and whether there is mural thrombus.The expression areas of smooth muscle actin and collagen fiber were measured by histochemistry and Masson trichrome stain.Scanning electron microscopy was used to observe the damage of endothelial cells.Results In the CDT group,all thrombus were dissolved completely (100%) in 6 hours,while in ST group were done by 20% (P<0.05).The value of PT and APTT was normal in procedure of thrombolysis.At the first day and the 4th week,there was none mural thrombus in the CDT group,but there was some mural thrombus in the ST group. The expression areas of smooth muscle actin and collagen fiber in the CDT group was less than that in the ST group(P<0.05) at the 4th week.At the first day,the degree of endothelium injury was Ⅰ～Ⅱ grade in the CDT group,while it was Ⅱ～Ⅲ grade in the ST group.At the 4th week,they were in Ⅱ～Ⅲ grade in both groups. Conclusions CDT can dissolve the thrombus effectively at low-medium dose,while ST only can achieve partial effects. CDT has demonstrated a good short-term effect and postponed the proliferation of intima in the treatment of DVT.