Performance comparison of aspirin assay between Anysis and VerifyNow: Assessment of therapeutic platelet inhibition in patients with cardiac diseases

BACKGROUND: Assessment of platelet inhibition for aspirin therapy is important to manage patients who are at potential risk of developing thrombotic and hemorrhagic complications. OBJECTIVE: This study aimed to evaluate a new platelet assay (Anysis-aspirin), compare it with VerifyNow-aspirin in patients with cardiac diseases, and analyze the aspirin resistance rates between the two devices. METHODS: Citrated blood samples were collected from patients with cardiac diseases referred for the aspirin response test. In the Anysis assay, a test result was provided with a blood flow migration distance (MD) until blood flow stoppage, which was comparable to aspirin reaction units (ARUs) obtained using VerifyNow. The measurements were simultaneously conducted using the two devices and compared. RESULTS: The MD without and with aspirin use was 160±33 and 254±23 mm, respectively (p < 0.0001). Compared with VerifyNow (reference), the sensitivity and specificity of Anysis-200 were 96.3 and 90.3%, respectively (area under the curve, 0.968). Furthermore, the aspirin resistance rate in aspirin-administered patients was 20.9%using VerifyNow and 16.5%for Anysis-200. The Cohen’s kappa coefficient between the two devices was 0.81, indicating an almost perfect agreement between the two devices. CONCLUSIONS: Anysis-aspirin, a novel aspirin assay for assessing platelet inhibition, showed excellent agreement with VerifyNow-aspirin with high accuracy and precision. The Anysis-aspirin assay would be used as a point-of-care test to assess aspirin non-responsiveness and abnormal platelet reactivity.