Platelets Count Alterations in Patients With Acute Coronary Syndrome: Epidemiology and Prognostic Role

Platelet count alterations (thrombocytopenia and thrombocytosis) are a common condition in patients hospitalised for acute coronary syndrome (ACS), both at disease onset and in the following recovery phase.1-3 Different factors can explain this phenomenon. Thrombocytopenia could be either due to neurohormonal activation and the inflammatory process following myocardial necrosis leading to increased macrophage activation with increased clearance of platelets, or to an immuno-modulated mechanism caused by the administration of antiaggregant/anticoagulant drugs (heparin, glycoprotein IIb/IIIa inhibitors, P2Y12 inhibitors).

Even the invasive treatment of coronaropathy during hospitalization, with angioplasty and stent implantation procedures and/or the eventual implantation of temporary mechanical blood circulation assistant devices [aortic counterpulsation, Impella, ECMO (Extracorporeal Membrane Oxygenation)], could further favour the phenomenon.4 Vice versa, thrombocytosis occurring during ACS has a reactive origin, caused by increased IL-6 production which, in turn, leads to an increase in thrombopoietin formation in the liver, causing a consequent stimulatory activity on megakaryocytes.2 Different studies have demonstrated a significant correlation between platelets count disorders and patient outcome (survival during hospitalization and in the immediate follow-up).5-11 This association has, however, often been considered an epiphenomenon of the underlying pathology. Platelets count alterations are, indeed, usually consensual to other hemogram alterations (anaemia and neutropenia), an indication of a coexisting medullar insufficiency (thrombocytopenia) or other heterogenous diseases such as cancer, iron deficiency or immuno-modulated diseases, usually associated with an increase in comorbidity indexes.12 Those alterations, moreover, can usually influence changes to the therapeutic approach (reduction/suspension of recommended standard therapies) and further condition the prognosis.13 Since a few years, the investigators have been established a cardiac-haematological collaboration aiming at finding early alterations in platelets count or, more generally, in cell blood count (CBC), collegially evaluating those alterations with a cardiologist and a haematologist (even in mild cases) and scheduling, on the basis of the aforementioned evaluations, a more precise and tailored therapeutic approach toward the specific patient needs in order to minimize the downgrading of potentially life-saving therapies.14 Until now, however, no precise evaluation of the impact that this strategy had in influencing the therapeutic approach and in improving patient outcome in our population has been performed.

A retrospective evaluation of consecutive ACS patients, their clinical, biohumoral and procedural characteristics and the adopted pharmacological treatments is, therefore, an important epidemiologic tool for the characterization of this phenomenon and for identifying potential associations which could suggest possible future therapeutic developments.