Valji K, Bookstein J J
Department of Radiology, University of California, San Diego 92103.
Invest Radiol. 1992 Nov;27(11):912-7. doi: 10.1097/00004424-199211000-00007.
The efficacy and speed of pharmacomechanical thrombolysis may be limited by thrombotic effects of activated platelets and thrombin within the lysing clot. The authors designed an animal model of subacute venous thrombosis which was used to evaluate the effect of intrathrombic versus intravenous heparin during thrombolysis.
Inferior vena cava (IVC) thrombosis was induced in rabbits by balloon catheter injury and placement of steel coils. Venacavagrams were obtained 48 hours later to document clot formation and for angiographic estimation of clot volume. Pulse-spray thrombolysis was performed by forceful injections of various agents through a catheter with multiple side holes spanning the clot. Most animals were given aspirin (30 mg orally) before treatment. After 1 hour of therapy, repeat venacavography was performed. Animals were killed, and residual clot weight was determined.
Occlusive IVC thrombi were present in 94% of rabbits at 2 days. Mean residual clot weight per milliliter of estimated initial clot volume (mg/mL) for the various treatment groups was as follows: saline (n = 5) 632 +/- 54; tissue-type plasminogen activator (t-PA) 3 mg, (n = 6) 443 +/- 162; t-PA 3 mg + heparin 750 U intravenously, (n = 7) 408 +/- 128; t-PA 3 mg + heparin 500 U intrathrombic + heparin 250 U intravenously, (n = 8) 213 +/- 166. Differences among these groups (except t-PA alone versus t-PA + intravenous heparin) were significant. The extent of lysis with intrathrombic + intravenous heparin was not significantly retarded by withholding aspirin (n = 6, 194 +/- 72), or improved by giving half the intrathrombic heparin before t-PA injections (n = 6, 280 +/- 158).
The results demonstrate the advantage of adjunctive intrathrombic + intravenous heparin over intravenous heparin alone in increasing the extent of pulse-spray thrombolysis in this IVC thrombosis model.
药物机械性溶栓的疗效和速度可能受到溶解血栓内活化血小板和凝血酶的血栓形成作用的限制。作者设计了一种亚急性静脉血栓形成的动物模型，用于评估溶栓期间血栓内注射肝素与静脉注射肝素的效果。
通过球囊导管损伤和放置钢圈在兔体内诱导下腔静脉（IVC）血栓形成。48小时后进行腔静脉造影以记录血栓形成情况并通过血管造影估计血栓体积。通过带有多个横跨血栓的侧孔的导管强力注射各种药物进行脉冲喷射溶栓。大多数动物在治疗前给予阿司匹林（口服30毫克）。治疗1小时后，再次进行腔静脉造影。处死动物并测定残余血栓重量。
2天时94%的兔存在闭塞性IVC血栓。各治疗组每毫升估计初始血栓体积的平均残余血栓重量（毫克/毫升）如下：生理盐水（n = 5）632±54；组织型纤溶酶原激活剂（t-PA）3毫克，（n = 6）443±162；t-PA 3毫克+静脉注射肝素750单位，（n = 7）408±128；t-PA 3毫克+血栓内注射肝素500单位+静脉注射肝素250单位，（n = 8）213±166。这些组之间的差异（t-PA单独使用与t-PA+静脉注射肝素除外）具有显著性。不给予阿司匹林（n = 6，194±72）时，血栓内注射+静脉注射肝素的溶解程度没有明显延迟，或在t-PA注射前给予一半血栓内肝素时（n = 6，280±158）溶解程度没有改善。
结果表明，在该IVC血栓形成模型中，辅助性血栓内注射+静脉注射肝素在增加脉冲喷射溶栓程度方面优于单独静脉注射肝素。
