Drug-eluting Vein Graft with Acetylsalicylic Acid-TicagrelorUnfractionated Heparin Complex Inhibits Early Graft Thrombosis

Abstract

Background: Bypass graft surgery remains to be an importanttreatment option for left main and multivessel coronary artery disease.Approximately 2% of saphenous vein grafts are lost immediately afterthe coronary artery bypass graft operations and 12% in the first monthdue to thrombosis.Aims: To administer one anticoagulant and two antiplatelet agents ina way that locally affects the vein graft before the bypass operationand to thereby analyse their effects on early graft thrombosis.Study Design: Animal experimentation.Methods: Since ticagrelor was used locally for the first time in thisstudy, its efficacy in combination with other drugs (acetylsalicylicacid, acetylsalicylic acid and ticagrelor, and acetylsalicylic acid +ticagrelor + unfractionated heparin) was examined on rats includingcontrol (untreated) and sham (pluronic gel) group (n=14 for eachgroup). Before the tunica adventitia layer of the femoral veins wasbypassed to the femoral artery, it was coated with the drug-elutingpluronic F-127 gel. The presence or absence of thrombus in the veingraft samples was recorded under light microscopy. In vein graftpreparations where thrombus was detected, the thrombus area (µm2)was calculated using the Axiovision software. Immunohistochemicalstaining was performed with the anti-rat von Willebrand factorpolyclonal antibody kit.Results: The number of preparations containing thrombus wassignificantly lower in the acetylsalicylic acid + ticagrelor +unfractionated heparin group than in the acetylsalicylic acid, control,and sham groups, according to the comparisons made on the 1st and3rd days (p=0.001 and 0.02, respectively). von Willebrand factorstaining was significantly lower in the acetylsalicylic acid + ticagrelor+ unfractionated heparin group than in the other groups on the 3rd day(p=0.005).Conclusion: Locally effective acetylsalicylic acid-ticagrelorunfractionated heparin complex has been shown to significantly reducethrombus formation in vein grafts in this experimental model. Localadministration of these drugs, which are routinely administered orallyjust before stent implantations, on the vein graft before the bypass isperformed can prevent the loss of vein grafts due to thrombus, therebyreducing the mortality and morbidity of these patients