High Residual Platelet Reactivity during Aspirin Therapy in Patients with Non-St Segment Elevation Acute Coronary Syndrome: Comparison Between Initial and Late Phases

• Published in: Arquivos brasileiros de cardiologia Vol. 113; no. 3; pp. 357 - 363
• Main Authors: Dracoulakis, Marianna Deway Andrade, Gurbel, Paul, Cattaneo, Marco, Martins, Herlon Saraiva, Nicolau, José Carlos, Kalil Filho, Roberto
• Format: Journal Article
• Language: English
• Published: Brazil Sociedade Brasileira de Cardiologia - SBC 01.09.2019; Sociedade Brasileira de Cardiologia (SBC)
• Subjects: Acute Coronary Syndrome - drug therapy; Aged; Agregação Plaquetária; Aspirin - pharmacology; Aspirin - therapeutic use; Aspirina/efeitos adversos; Aspirina/uso terapêutico; Blood Platelet Disorders - drug therapy; Blood Platelets - drug effects; Blood Platelets - metabolism; CARDIAC & CARDIOVASCULAR SYSTEMS; Female; Humans; Idoso; Isquemia Miocárdica; Male; Middle Aged; Non-ST Elevated Myocardial Infarction - physiopathology; Original; Platelet Aggregation Inhibitors - pharmacology; Platelet Aggregation Inhibitors - therapeutic use; Platelet Function Tests; Prospective Studies; Risk Factors; Síndrome Coronariana Aguda; Idoso; Isquemia Miocárdica; Aspirina/efeitos adversos; Aspirina/uso terapêutico; Platelet Aggregation/drug effects; Aged; Síndrome Coronariana Aguda; Myocardial Ischemia; Agregação Plaquetária; Acute Coronary Syndrome; aspirin/therapeutic use; Aspirin/adverse effects
• ISSN: 0066-782X; 1678-4170; 1678-4170
• DOI: 10.5935/abc.20190146

High platelet reactivity (HPR) during therapy with acetylsalicylic acid (ASA) is a poor prognostic factor in acute coronary syndromes (ACS). The prevalence of HPR during ACS is greater than that reported in stable diseases. However, it is unclear whether this prevalence of HPR is a transient phenomenon or a characteristic of this high-risk population. The main objective is to compare the effects of ASA on platelet function in the initial and late phases of ACS in a single population. Secondary objectives are: correlation between the tests between themselves and the relationship between the tests and the variation of the inflammatory markers (C-reactive protein and interleukin-6). Seventy patients with non-ST segment elevation (NSTE) ACS in use of 100-200 mg of ASA per day for at least 7 days were prospectively studied. Platelet function was assessed in the first 48 hours and subsequently after 3 months using four methods: VerifyNow™ (VFN), whole blood platelet aggregation (WBPA) with arachidonic acid (AA) and collagen as agonists, and platelet function analyzer (PFA). The level of statistical significance considered was < 0.05. According to the more specific methods (WBPA with AA and VFN), the incidence of HPR was significantly higher in the early phase than in the late phase: WBPA with AA: 31% versus 13%, p = 0.015; VFN: 32% versus 16%, p = 0.049. The other methods tested, which were less specific for ASA, did not show significant differences between phases. The correlation between the methods was weak or moderate (r ranging from 0.3 to 0.5, p < 0.05), and there were no significant associations between HPR and inflammatory markers. The prevalence of HPR during AAS therapy, assessed by specific methods for cyclooxygenase 1 (COX-1), is higher during the acute phase than in the late phase of NSTE ACS.