Assessment of prosthetic vascular graft thrombogenicity using the technetium-99m labeled glycoprotein IIb/IIIa receptor antagonist DMP444 in a dog model

D. Scharn, W. Oyen, P. Klemm, M. Wijnen and J. vanderVliet

Department of Surgery, University Medical Center Nijmegen, 'St Radboud', PO Box 9101, 6500 HB, Nijmegen, The Netherlands.
Dec, 2002


Prosthetic graft patency greatly depends on graft thrombogenicity. The concept of graft thrombogenicity is poorly understood and difficult to measure or quantify. In a study we tested the experimental radiopharmaceutical DMP444 and developed a suitable dog model. This agent is a radiolabelled ((99m)Technetium) glycoprotein IIb/IIIa receptor antagonist with a high affinity for activated platelets. It binds to platelets that are intimately involved in thrombus formation. The agent does not affect thrombocyte function, when used in a dose necessary for imaging. DMP444 does not require platelet harvesting and processing. Early imaging of thrombocyte aggregation sites such as vascular prostheses is possible within 4 hours after injection.Adult Beagle dogs weighing 12-15 kg were used for the experiments. In 16 dogs a prosthetic patch was sewn onto the abdominal aorta (Bovine pericard: n=4, Dacron: n=6, Human Umbilical Vein: n=6). Imaging cycles after injection of (99m)Technetium-labelled DMP444 were performed on days 1, 7, 14 and 28 after surgery.We noticed differences in thrombus formation on the tested graft materials. The bovine pericard patches (n=4) showed a relatively high rate of thrombocyte aggregation. In the Dacron patches (n=6) aggregation was not seen. In 1 of 6 cases of human umbilical vein patches a measurable focal aggregation was recorded.The method outlined in this study is a relatively simple and reproducable method to visualize thrombocyte aggregation.