The effect of aspirin on mean platelet volume in patients with paroxysmal atrial fibrillation.

Aspirin is one of the preferred therapies in the primary prevention of ischemic stroke in paroxysmal atrial fibrillation (PAF). Mean platelet volume (MPV) is a marker of platelet size and activation. Increased MPV reflects active and large platelets. The present observational study was designed to investigate whether aspirin treatment does affect MPV levels in patients with PAF. The study included 101 patients who were detected to have PAF by 24-hour Holter monitoring and divided into two groups based on aspirin treatment [ASA (+) and ASA (-)]. MPV was measured. Patients with aortic and mitral stenosis, hyperthyroidism, hypothyroidism, malignancy, infection, and pregnancy were excluded from the study. Of the 101 patients, 50 had no antiplatelet therapy and 51 had daily aspirin (100 mg) intake. Mean age of the patients was 66 ± 10 years and 35 (68%) were male in ASA (+) group. There was no difference in median levels of MPV (9.9 vs. 10.2 fl, respectively; p = 0.9) between groups. Both uni- and multivariate logistic regression analyses did not show an association between MPV and ASA use. Our results indicate that MPV as a predictive marker of platelet size and activity is not affected by aspirin use in patients with PAF.