Atherosclerosis is a process of gradual lipid deposits in arteries. The most dangerous place for atherosclerosis is in the coronary vessels were gradual or sudden blockade can lead to angina and even myocardial infarction,w here the heart is unable to receive blood for its own survival, and thus stops working. Recurrent episodes of unstable angina, that is angina occurring without stress or otherwise explained is an important indication for stenting. Some of the other indication for cardiac stenting are 1) acute or threatened vessel occlusion after elective PTCA (“bail-out” – in this there may be a sudden occlusion of the coronary artery following angiography); 2) acute myocardial infarction (AMI); 3) unstable angina with threatened vessel occlusion; 4) suboptimal primary results (angiographically assessed) after PTCA or cardiac bypass procedure; 5) elective stent implantation to prevent restenosis. In all these situation there is critical block in the coronary vessels, leading to cardiac ischemia
With newer stents like drug-eluting stents coming up, where the stents are coated with a drug (like paclitaxel) which is slowly to block cell proliferation, and chances of reblockage. A possible trial can be a controlled randomized trial of the drug eluting stent versus the conventional stent in patients with MI. such a study would involve matching of study patients into two groups in terms of age, sex, type of vessel blockade. The possible factors that may be studied, are 1) time to insert stent, 2) restenosis rates 3) complications 4) blood study to assess side effect of drug 5) post stenting benefit in terms of echocardiography analysis, and increase in exercise performance, and 6) episodes of recurrent chest pain. Such a study may also be done with comparison of the drug eluting stent versus coronary bypass procedure, keeping the same factors constant.
1 Drug-eluting stent – Wikipedia, the free encyclopedia -en.wikipedia.org/wiki/Drug-eluting_stent, accessed on 31/3/08
2 Sänger A, Krakau I, Emmerich K, Müller A, Gülker H. [Differential indication for coronary stent implantation. Comparative study of acute cardial and vascular complications in relation to the indication. Dtsch Med Wochenschr. 1998 Jul 3;123(27):821-6.