Các kết quả này trong một thành phần đại thực bào tế bào bọt lớn, giống như vệt béo chứ không phải là tổn thương con người restenotic. Ngược lại, các tính năng histopathologic neointima thu được trong các mô hình lợn chặt chẽ tương tự như neointima con người | Restenosis etiologies and prevention development of lesions. The latter results in a large macrophage foam cell component resembling fatty streaks rather than human restenotic lesions. Conversely the histopathologic features of neointima obtained in porcine models closely resemble the human neointima and the amount of neointimal thickening is proportional to injury severity. This has allowed the creation of an injury-neointima relationship that can be used to evaluate the response to different therapies. However the repair process in the pig coronary artery injury model using normal coronary arteries is certainly more rapid and may be different from the response to balloon angioplasty that characterizes human coronary atherosclerotic plaques. The major limitation in the use of animal models of restenosis is that agents effective in reducing neointima in those models are ineffective when transferred into the clinical arena. Many explanations might support those differences. Different animal species types of artery degree of arterial injury volume of neointima drug dosages and timing regimens and atherosclerotic substrate might be considered. To address this concern we believe that before transferring the results obtained in animal models into clinical trials standardization of injury type the method of measurement and the dose and timing of drug administration among different animal models is necessary. Other issues in the study of restenosis are the limitations in the design of restenosis clinical trials. Incomplete angiographic follow up leading to the occurrence of selection and withdrawal biases followed by inadequate power due to small patient sample leading to the potential of p type II errors are the most common problems. Non-uniform definitions of angiographic restenosis and poor correlation between angiographic and clinical outcome are other problems that need to be resolved when comparing different trial results. Future restenosis studies should utilize .
