Clopidogrel stents

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. 

According to ACC/AHA 2007 guidelines, clopidogrel is indicated for up to 12 months in NSTE ACS patients, with a minimum treatment duration of 1 month after placement of a bare-metal stent and 12 months after placement of a sirolimus- or paclitaxel-coated stent. 

Clopidogrel should be considered for most patients, but the duration of therapy is individualized according to the type of ACS and whether the patient is treated medically or undergoes stent implantation. 

For patients with STEMI treated medically without revascularization, clopidogrel can be given for 14 to 28 days. If a stent has been implanted, clopidogrel can be continued for up to 12 months in patients at low risk for bleeding. 

Acute coronary syndrome For patients with acute coronary syndrome (unstable angina/non-Q-wave Ml) including patients who are to be managed medically and those who are to be managed with percutaneous coronary intervention (with or without stent) or coronary artery bypass graft (CABG), clopidogrel has been shown to decrease the rate of a combined endpoint of cardiovascular death. Ml, or stroke, as well as the rate of a combined endpoint of cardiovascular death. Ml, stroke, or refractory ischemia. 

Eisenstein EL, Anstrom KJ, Kong DF, et al. Clopidogrel use and long-term clinical outcomes after drug-eluting stent implantation. JAMA 2007 297 159-168. 

Clopidogrel is indicated for prevention of vascular ischaemic events in patients with symptomatic atherosclerosis. It is also used, along with aspirin, for the prevention of thromboembolism after placement of an intracoronary stent. Platelet inhibition can be demonstrated two hours after a single dose of oral clopidogrel, but the onset of action is slow, so that a loading-dose is usually administered. Although rare, severe neutropenia and also thrombotic thrombocytopenic purpura may occur. 

I 5 Kastrati A, Mehilli J, Schuhlen H, et al. Intracoronary stenting and antithrombotic regimen-rapid eariy action for coronary treatment study investigators. A clinical trial of abciximab in elective percutaneous coronary intervention after pretreatment with clopidogrel. N Engl J Med 2004 350 232-238. 

Thus, clopidogrel (LD300 mg + 75 mg/day for one month) is the standard of care after bare metallic stent implantation. 

Bertrand ME, Rupprecht HJ, Urban R Gershlick AH, Investigators FT, Double-blind study ofthe safety of clopidogrel with and without a loading dose in combination with aspirin compared with ticlopidine in combination with aspirin after coronary stenting the clopidogrel aspirin stent international cooperative study (CLASSICS). Circulation 2000 102 624-629,... 

Bhatt DL, Bertrand ME, Berger PB, et al, Meta-analysis of randomized and registry comparisons of ticlopidine with clopidogrel after stenting, J Am Coll Cardiol 2002 39 9-14,... 

Waksman R, Ajani AE, Pinnow E, et al, Twelve versus six months of clopidogrel to reduce major cardiac events in patients undergoing gamma-radiation therapy for in-stent... 

Waksman R, Ajani AE, White RL, et al. Prolonged antiplatelet therapy to prevent late thrombosis after intracoronary gamma-radiation in patients with in-stent restenosis Washington Radiation for In-Stent Restenosis Trial plus 6 months of clopidogrel (WRIST PLUS). Circulation 2001 103 2332-2335. 

Ahn JC, Song WH, Kwon JA, et al. Effects of cilostazol on platelet activation in coronary stenting patients who already treated with aspirin and clopidogrel. Korean J Int Med 2004 19 230-236. 

Eptifibatide (Integrelin), a cyclic heptapeptide based on a peptide sequence in snake venom, is a GPIIb/llla inhibitor used in conjunction with heparin and aspirin for the treatment of ACS or in PCI, with or without stenting and clopidogrel (Table I). 

Limited data are available to link clopidogrel nonresponsiveness to the occurrence of thrombotic events. Matetzky et al. studied clopidogrel responsiveness in patients undergoing stenting for acute ST-elevation Ml. They found that patients who exhibited the highest quartile of ADP-induced aggregation had a 40% probability for a recurrent cardiovascular... 

I 5 Gurbel PA, Bliden KR Samara W, et al. Clopidogrel effect on platelet reactivity in patients with stent thrombosis results of the CREST Study. J Am Coll Cardiol 2005 46 1827-1832. 

Gurbel PA, Bliden KB Tantry US. The effect of clopidogrel with and without eptifibatide on tumor necrosis factor-alpha and C-reactive protein release after elective stenting Results of the CLEAR PLATELETS-lb study. J Am Coll Cardiol 2006 48 2186-2191. 

Gurbel PA, Bliden KR Hiatt BL, O Connor CM. Clopidogrel for coronary stenting response variability, drug resistance, and the effect of pretreatment platelet reactivity. Circulation 2003 107 2908-2913. 

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