[Experimental model of early chronic pelvic vein thrombosis with occlusion spirals and thrombin]

To create an early chronic venous thrombosis with good comparability to human venous thrombosis for evaluation of new thrombectomy systems.

Using a transjugular approach, three dacron-fibered occlusion coils were placed into the proximal common iliac vein of 7 pigs under general anesthesia. The coiled common iliac vein was blocked by the use of a balloon occlusion catheter, and 500 units of thrombin were injected into the "coil basket". One hour later, the balloon catheter was deflated and removed. After three days, the thrombus was controlled by phlebography and histology.

The induction of thrombi was successful in all cases. The mean length of the thrombi was 60 mm and the mean diameter was 10 mm. Histologically, the thrombus consisted of a laminated plug of fibrin and platelets as well as clots in the sense of a mixed thrombus with signs of a beginning organization. Considering the cellular composition and the histological aspect, the thrombi met the criteria for early chronic venous thrombosis in humans.

The presented experimental thrombus model is easy to perform and enables a good comparability to early chronic human venous thrombosis.