Stent thrombosis: Consider also low response to antiplatelets

doi:10.1136/bmj.39086.925718.1F

BMJ 2007;334:57 (13 January), doi:10.1136/bmj.39086.925718.1F

Letters

Stent thrombosis

Consider also low response to antiplatelets

The first 150 words of the full text of this article appear below.

Gershlick and Richardson suggest that the increasedrisk of stent thrombosis in drug eluting stents compared withbare metal stents is attributable to prolonged exposure of thestent struts.¹ We suggest that stent thrombosis is partly attributableto clopidogrel and aspirin "low responders," and that this patientsubgroup should be identified before intervention and alternativeoral antiplatelet strategies considered.

In multiple trials, 5-40% of patients treatedwith clopidogrel displayed suboptimal inhibition of plateletaggregation when evaluated ex vivo by optical aggregometry andflow cytometry. These patients are often deemed clopidogrellow responders. A similar phenomenon—aspirin low responders—is reported in 5-20% of cases. The latter group are more likelyto be women and have diabetes mellitus and a reduced responseto clopidogrel.²

Bedside platelet inhibition assays have beenavailable for some time (for example, VerifyNow P2Y12 assay,Accumetrics USA) and can identify aspirin and clopidogrel lowresponders beforehand.

We propose . . . [Full text of this article]

Andrew J Wiper, cardiology registrar a_wiper@yahoo.com, David H Roberts, consultant interventional cardiologist

¹ Lancashire Cardiac Centre, Blackpool Victoria Hospital, Blackpool FY3 8NR