Aspirin restenosis

Schwartz et al. (29) examined the role of antiplatelet therapy in preventing restenosis following balloon angioplasty. They randomized 376 patients to receive either aspirin plus dipyridamole or placebo (similar to previous bypass studies). The active treatment arm received aspirin (330 mg) and dipyridamole (75 mg) three times daily for 24 hours prior to the procedure eight hours before PTCA, the oral dipyridamole was replaced with intravenous dipyridamole (10 mg/hour for 24 hours)—the oral aspirin was continued ... 

Schwartz L, Bourassa MG, Lesperance J, et al. Aspirin and dipyridamole in the prevention of restenosis after percutaneous transluminal coronary angioplasty. N Engl J Med 1988 318 1714-1719. 

Ticlopidine Only if intolerant to clopidogrel At least 250 mg bd Synergistic with aspirin in reducing platelet aggregation (6) and reducing instent restenosis (7) Concern over associated incidence of agranulocytosis (8,9), frequent gastric intolerance and skin rashes Sequential FBC required at follow-up... 

Napoli C, Aldini G, Wallace JL, Maf-fei R, Lerman LO, Ignarro LJ. 2002. Efficacy and age-related effects of nitric oxide-releasing aspirin on experimental restenosis. Proc. Natl. Acad. Sci. USA 99 1689-94... 

Abciximab (ReoPro) is the Fab fragment of a humanized monoclonal antibody directed against the a bp3 receptor. It also binds to the vitronectin receptor on platelets, vascular endothelial cells, and smooth-muscle cells. The antibody is used in conjunction with percutaneous angioplasty for coronary thromboses, and when used in conjunction with aspirin and heparin, has been shown to be quite effective in preventing restenosis, recurrent myocardial infarction, and death. 

A more frequent complication is restenosis of the angioplasty site which occurs in 25-30% of patients over 6-9 months " . Pathological studies in patients with recurrence of symptoms are infrequent but demonstrate proliferation of fibroblasts and vascular smooth muscle cells overlying and distinct from the traumatized atherosclerotic plaque . Similar lesions have been described in early atherosclerosis and there is evidence to suggest a role for platelets in the development of such lesions , possibly through release of platelet-derived growth factors which stimulate fibroblast and vascular smooth muscle proliferation . Thus, depletion or inhibition of platelets prevents the development of atherosclerosis in animal models and aspirin inhibits the accelerated coronary atherosclerosis which occurs in cardiac transplant recipients. Furthermore, restenosis is more frequent when there is evidence of a thrombus at the angioplasty site consistent with previous... 

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