Asociación entre el volumen plaquetario medio y la resistencia a aspirina e inhibidores del receptor P2Y12 en pacientes ancianos con sindrome coronario agudo;
Association between Mean Platelet Volume and Resistance to Aspirin and P2Y12 Receptor Inhibitors in Elderly Patients with Acute Coronary Syndrome

Introducción La presencia de 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. Objetivo Evaluar si existe asociación entre la presencia de resistencia a la aspirina (AAS) e inhibidores del receptor P2Y12 (iP2Y12) y el VPM en pacientes mayores de 65 años con SCA. Materiales 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 agregación plaquetaria entre las 12 y 24 horas postcarga (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 consideró el punto final combinado de muerte global y reinternación cardiovascular. Resultados Se incluyeron 195 pacientes, todos recibieron AAS e iP2y12 (120 recibieron clopidogrel y 75 Ticagrelor). Grupo 1 (19%), Grupo 2 (34.4%) y grupo 3 (46.7%). El VPM  se asoció a la resistencia a ambos antiagregantes (OR 1.02 (IC95% 1.01-1.05), p=0.03. A su vez, el VPM y el GRACE fueron predictores independientes del punto combinado (HR 1.03 (IC95% 1.01-1.07), p=0.04 y HR 1.02 (IC95% 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.

Background: Antiplatelet resistance and mean platelet volume (MPV) are event predictors in acute coronary syndrome (ACS), buttheir association has been poorly studied.Objective: The aim of this study was to evaluate the association between MPV and resistance to aspirin (ASA) and P2Y12 receptorinhibitors (P2Y12i) in elderly patients with ACS.Methods: Patients over 65 years old diagnosed with ACS were included in the study. They were divided into group 1 (resistance toboth antiplatelet agents), group 2 (resistance to one antiplatelet agent) and group 3 (no resistance to antiplatelet agents). Plateletaggregation was measured between 12 and 24 hours postloading (by light transmission aggregometry). Resistance to P2Y12i wasconsidered as maximum percentage of aggregation (MPA) with adenosine diphosphate (ADP) >60% and resistance to ASA as MPAwith arachidonic acid (ARA) >20%. The composite endpoint of global death and cardiovascular re-hospitalization was consideredduring follow-up.Results: One hundred and ninety five patients included in the study received ASA and P2Y12i (120 received clopidogrel and 75ticagrelor). Nineteen percent of patients belonged to group 1, 34.4% to group 2 and 46.6% to group 3. Mean platelet volume wasassociated with resistance to both antiplatelet agents [OR 1.02 (95% CI 1.01-1.05), p=0.03], while MPV and the GRACE score wereindependent 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.