RESUMO
RESUMEN Introducción: La resistencia a antiagregantes y el volumen plaquetario medio (VPM) son predictores de eventos en el síndrome coronario agudo (SCA). La asociación entre ambos ha sido poco estudiada. Objetivos: Evaluar si existe asociación entre la resistencia a la aspirina (AAS) e inhibidores del receptor P2Y12 (iP2Y12) y el VPM en pacientes mayores de 65 años con SCA. Material y métodos: Se incluyeron pacientes mayores de 65 años con diagnóstico de SCA. Se dividieron en: grupo 1 (resistencia a ambos antiagregantes), grupo 2 (a uno de los antiagregantes) y grupo 3 (a ningún antiagregante). Se midió la agregación plaquetaria entre las 12 y 24 horas poscarga (por light transmission aggregometry). Se consideró resistencia a iP2Y12 a un porcentaje máximo de agregación (PMA) con ADP > 60% y a la AAS a un PMA con ARA > 20%. En el seguimiento se consi-deró el punto final combinado de muerte global y reinternación cardiovascular. Resultados: Se incluyeron 195 pacientes que recibieron AAS e iP2y12 (120 recibieron clopidogrel y 75 ticagrelor); grupo 1 (19%), grupo 2 (34,4%) y grupo 3 (46,6%). El VPM se asoció a la resistencia a ambos antiagregantes (OR 1,02 (IC 95% 1,01-1,05), p = 0,03. A su vez, el VPM y el GRACE fueron predictores independientes del punto combinado (HR 1,03 (IC 95% 1,01-1,07), p = 0,04 y HR 1,02 (IC 95% 1,01-1,04), p = 0,02), respectivamente. Conclusiones: El VPM se asoció a la presencia de resistencia a ambos antiagregantes. En el seguimiento el VPM y el score GRACE fueron predictores del punto combinado.
ABSTRACT Background: Antiplatelet resistance and mean platelet volume (MPV) are event predictors in acute coronary syndrome (ACS). However, the association between both has been poorly studied. Objective: The aim of this study was to evaluate the association between MPV and resistance to aspirin (ASA) and P2Y12 receptor inhibitors (P2Y12i) in elderly patients with ACS. Methods: Patients over 65 years old with diagnosis of ACS were included in the study. They were divided into group 1 (re-sistance to both antiplatelet agents), group 2 (resistance to one antiplatelet agent) and group 3 (no resistance to antiplatelet agents). Platelet aggregation was measured between 12 and 24 hours postload (by light transmission aggregometry). Resis-tance to P2Y12i was considered as maximum percentage of aggregation (MPA) with adenosine diphosphate (ADP) >60% and resistance to ASA as MPA with arachidonic acid (ARA) >20%. The composite endpoint of global death and cardiovascular re-hospitalization was considered during follow-up. Results: One hundred and ninety five patients included in the study received ASA and P2Y12i (120 received clopidogrel and 75 ticagrelor). Nineteen percent of patients belonged to group 1, 34.4% to group 2 and 46.6% to group 3. Mean platelet volume was associated with resistance to both antiplatelet agents [OR 1.02 (95% CI 1.01-1.05), p=0.03], while MPV and the GRACE score were independent predictors of the composite endpoint [HR 1.03 (95% CI 1.01-1.07), p=0.04] and [HR 1.02 (95% CI 1.01-1.04), p=0.02], respectively. Conclusions: Mean platelet volume was associated with the presence of resistance to both antiplatelet agents. During follow-up, MPV and the GRACE score were predictors of the composite endpoint.