Platelet volume is a marker of platelet function and activation. An elevated mean platelet volume (MPV) is associated with acute coronary syndromes (ACS). Recurrent cardiovascular events were found to be higher in patients with aspirin resistance. In this study, we investigated the effect of MPV on prognosis of patients with and without aspirin resistance by PFA-100 in settings of non-ST-segment elevated ACS. Two hundred and twenty patients with ACS were followed for an average of 14.86 ± 5.93 months for the occurrence of death, myocardial infarction (MI) and revascularization. Aspirin effect on platelet function was assessed by PFA-100. According to MPV value and aspirin resistance status, patients were divided into four groups. Group 4 (with an elevated MPV and aspirin resistance) was significantly associated with worse prognosis for composite endpoint (death, MI and revascularization), death and MI (for all, log–rank P < 0.0001). Multivariate analysis showed that presence of an elevated MPV and aspirin resistance was an independent predictor of composite endpoint [hazard ratio 8.21, 95% confidence interval (CI) 3.48–19.35, P < 0.0001], death (hazard ratio 5.48, 95% CI 1.62–18.53, P = 0.006) and MI (hazard ratio 4.44, 95% CI 1.57–12.58, P = 0.005). Presence of an elevated MPV and aspirin resistance was significantly associated with death, MI and the composite endpoint, due to the lack of beneficial effect of aspirin on activated platelets. Patients with ACS, especially in the presence of an elevated MPV may benefit from the evaluation of aspirin resistance for risk stratification.
aCardiology Department, Siyami Ersek Thoracic and Cardiovascular Surgery Center, Istanbul, Turkey
bDepartment of Cardiology, School of Medicine, Gaziantep University, Gaziantep, Turkey
cDepartment of Cardiology, Kocaeli Acibadem Hospital, Kocaeli, Turkey
Received 5 January, 2009
Revised 13 May, 2009
Accepted 29 July, 2009
Correspondence to Orhan Ozer, MD, Department of Cardiology, School of Medicine, Gazintep University, Gaziantep 27310, Turkey Tel: +90 342 3606060 76284; fax: +90 342 360 3928; e-mail: email@example.com