The Impact of Thrombocytopenia on Outcome in Patients with Acute Coronary Syndromes: A Single Center Retrospective Study

Background. In acute coronary syndromes (ACS), treated by combined antithrombotic therapy and percutaneous coronary interventions (PCI), thrombocytopenia may occur. Our aim was to evaluate predictors and the impact of thrombocytopenia on mortality in high-risk ACS patients. Methods. We retrospectively evaluated high-risk ACS patients. Thrombocytopenia was defined as platelet count <140.000/mL or a drop in platelet count of >50% during in-hospital stay. We compared demographic, laboratory, clinical, and mortality data between nonthrombocytopenic and thrombocytopenic ACS patients and evaluated independent predictors of thrombocytopenia. Results. In 371 ACS patients, thrombocytopenia was observed in 21.3%. Thrombocytopenic patients were significantly older and, less likely treated by PCIs (72.1% versus 89.7%, p < 0.001) and combined antithrombotic therapy, with increased incidence of in-hospital complications and the use of additional treatments, but with increased mortality at 30 days (27.8% versus 10.2%, p < 0.001) and 6 months (35.4% versus 13.6%, p < 0.001) when compared to nonthrombocytopenic patients. The use of antibiotics, transfusions, insertion of intra-aortic balloon pump (IABP), and prior stroke independently predicted thrombocytopenia. Conclusions. Thrombocytopenia, observed in about 20% of high-risk ACS patients, was associated significantly with in-hospital complications and mortality. Predictors of thrombocytopenia were the use of antibiotics, transfusions, insertion of IABP, and prior stroke.