What is coronary stent thrombosis?
Stent thrombosis is a thrombotic occlusion of a coronary stent. This is usually an acute process in contrast to restenosis, which is a gradual narrowing of the stent lumen due to neointimal proliferation. Stent thrombosis often results in an acute coronary syndrome, while restenosis often results in anginal symptoms.
What are the types of stent thrombosis?
Based on the underlying stent, stent thrombosis should be divided into categories of a bare-metal stent (BMS), a first-generation drug-eluting stent (DES), and second-generation DES.
Why do drug eluting stents cause thrombosis?
The drug coating is depleted and there is no new tissue coating the stent struts. As a result, blood flows directly over a “bare” surface, a perfect set-up for thrombus formation.
What is subacute stent thrombosis?
Subacute stent thrombosis was defined as recurrent ischemia and documented vessel occlusion at the site of stent implantation within 7 days after successful index PCI. Successful PCI was defined as a patent vessel at the treatment site with anterograde TIMI-3 flow and angiographic residual stenosis less than 50%.
What causes stent thrombosis?
The primary factors contributing to stent thrombosis are inadequate stent deployment, incomplete stent apposition, residual stenosis, unrecognized dissection impairing blood flow, and noncompliance with dual antiplatelet therapy (DAPT). Noncompliance with DAPT is the most common cause of stent thrombosis.
How is stent thrombosis treated?
Dual antiplatelet therapy with aspirin and a thienopyridine is currently recommended for PCI patients in whom stents are implanted on the basis of randomized trials showing reduced rates of stent thrombosis with aspirin plus ticlopidine compared to aspirin alone or aspirin plus warfarin.
Why does stent thrombosis occur?
What is the single most important risk factor for stent thrombosis?
The most important risk factor for early or late ST after BMS or first-generation DES implantation is premature discontinuation of DAPT. For BMS, this period appears to be 30 days, and for first-generation DES, it is at least 6 to 9 months.
How can stent thrombosis be prevented?
Potential stent modifications to reduce stent thrombosis have included improving the biocompatibility of the stent and polymer, using bioabsorbable polymers, eliminating the polymer entirely, and/or using stent surface modifications to stimulate vascular endothelialization.