Stents subacute thrombosis

Berkompas DC. Abeiximab combined with angioplasty in a patient with renal artery stent subacute thrombosis. Cathet Cardiovasc Diagn 1998 45(3) 272-274. 

In 2006, however, focus shifted to another rare but potentially catastrophic event known as late stent thrombosis, which, in contrast to subacute thrombosis, occurs months to years after stent placement. It usually occurs before endothelialization is complete. For bare metal stents, this takes a few weeks. However, in drug eluting stents, this process of endotheliazation is delayed [68]. This complication... 

Baily SR, Paige S, Lunn A, et al. Heparin coating of endovascular stents decreases subacute thrombosis in a rabbit model, Circulation I 992 86(suppl) l I 86. 

Local delivery of bevacizumab at the vessel wall can be performed by dedicated stents coated with PC. The PC polymer mimics the chemical structure of the PC headgroup, which makes up 90% of phospholipids in the outer membrane of a red blood cell. PC has been shown to decrease protein absorption and platelet adhesion thereby we can expect that the PC coating reduces the thrombus formation of the stainless steel stent, allowing the prevention of subacute thrombosis. Both in vitro and in vivo researches have demonstrated that PC-based polymers are effective in improving the biocompatibility of inert materials (60-62). 

Sekiguchi M, Hoshizaki H, Adachi H, Ohshima S, Taniguchi K, Kurabayashi M, Effects of antiplatelet agents on subacute thrombosis and restenosis after successful coronary stenting A randomized comparison of ticlopidine and cilostazol. Circ J 2004 68(7) 6I0-6I4,... 

For patients undergoing primary PCI, clopidogrel is administered as a 300-to 600-mg loading dose followed by a 75 mg/day maintenance dose, in combination with aspirin 325 mg once daily, to prevent subacute stent thrombosis and long-term cardiovascular events. 

Ajzenberg N, Aubry R Huisse MG, et al. Enhanced shear-induced platelet aggregation in patients who experience subacute stent thrombosis a case-control study J Am Coll Cardiol 2005 45 1753-1756. 

Heparin-coated Palmaz-Schatz, Wiktor, Jostent, BX Velocity, and beStent have been investigated in clinical studies. All studies showed that heparin-coated stents are safe, even in high-risk lesions. When compared with balloon angioplasty, heparin-coated stents could significantly reduce the rate of subacute stent thrombosis and the late restenosis. However, no significant difference of restenosis was observed between the heparin-coated stent and the bare stent control. 

Sheth S, Dev V Jacobs H, et al. Prevention of subacute stent thrombosis by polymer-polyethylene oxide-heparin coating in rabbit carotid artery [abstr]. J Am Coll Cardiol 1995 25 348A. 

Gupta V Aravamuthan BR, Baskerville S, et al, Reduction of subacute stent thrombosis (SAT) using heparin-coated stents in a large-scale, real world registry. J Invasive Cardiol 2004 ... 

In addition, attempts to deliver radiation therapy to symptomatic de novo or restenotic native coronary-artery lesions included the deployment of very low activity 32P radioactive stents. Preliminary data for clinical endpoints (e.g., subacute stent thrombosis, TLR, and death at 30 days) appeared promising, but the long-term angiographic follow-up revealed an unacceptable restenosis rate at or beyond the stent edges (21,22). Consequently, further studies to evaluate this technique were abandoned. 

Structure of BRILLIANT EU. Abbreviations IVUS, intravascular ultrasound MACE, major adverse cardiac events MLA, minimal luminal area MLD, minimal luminal diameter QCA, qualitative coronary angiography SAT, subacute stent thrombosis TLR, target lesion revascularization TVF, target vessel failure TVR, target vessel revascularization. 

Cilostazol is a phosphodiesterase inhibitor that reduces platelet aggregation, vascular smooth muscle proliferation and also has vasodilatory effects. Earlier studies comparing cilostazol and aspirin to ticlodipine and aspirin identified no significant increase in the subacute stent thrombosis rate (21-23). Indeed, the latter has been supported by comparison of this combination to clopidogrel and aspirin (24). Two recent trials, however, have demonstrated that a much higher proportion of patients develop subacute stent thrombosis when taking cilostazol as compared with ticlodipine (25,26). The data from these trials are summarized in Table I. 

T ble 1 A comparison of the rates of subacute stent thrombosis in trials comparing cilostazol with ticlodipine or clopidogrel... 

Cilostazol Elective (21-25) and emergency (22-26) PCI 100 mg twice daily Possibility of increased subacute stent thrombosis rate (21-26)... 

Initial anecdotal reports of subacute stent thrombosis first surfaced after introduction of the Cypher stent in 2003 when 360 cases (out of a total 575,000 stents implanted) were reported. However, a significant risk... 

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