Aspirin resistance and elevated MPV linked to poor outcomes in ACS patients
MedWire News: Aspirin resistance combined with an elevated mean platelet volume (MPV) is associated with a poor prognosis in patients with acute coronary syndromes (ACS), Turkish researchers report.
“Platelet volume is a marker of platelet function and activation, and MPV has recently been appreciated as a biomarker of cardiovascular disease,” remark Orhan Ozer (Gazintep University) and colleagues.
“It may be hypothesized that the effect of an elevated MPV on the prognosis of ACS patients with aspirin resistance is more prominent than that on those without aspirin resistance due to the lack of beneficial antiplatelet effects of aspirin,” say the researchers.
To investigate, Ozer and team followed-up 220 patients with non-ST-segment elevated ACS for an average of 14.9 months for the occurrence of death, myocardial infarction (MI), and revascularization.
The researchers used the PFA-100 test to assess aspirin resistance. They found that 84 (38.1%) patients were aspirin resistant when resistance was defined as a collagen/epinephrine-closure time of 170 seconds or more despite taking aspirin.
Patients were divided into four groups according to their MPV values (normal vs elevated) and aspirin resistance status (resistant vs non-resistant). Patients with an elevated MPV and aspirin resistance had a significantly worse prognosis for the composite endpoint of death, MI, and revascularization, and for death and MI alone, compared with the other three groups.
Multivariate analysis revealed that the presence of aspirin resistance and an elevated MPV was independently associated with a 5.5-fold increased risk for death, a 4.4-fold increased risk for MI, and an 8.2-fold increased risk for the composite endpoint of death, MI, and revascularization, compared with patients with normal MPV and no aspirin resistance.
“These findings suggested that an elevated MPV affects prognosis especially in the patients with aspirin resistance due to lack of the antiplatelet effects of aspirin,” conclude Ozer and co-authors in the journal Blood, Coagulation and Fibrinolysis.
They add: “Patients with ACS, especially in the presence of an elevated MPV may benefit from the evaluation of aspirin resistance for risk stratification.”
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By Laura Dean