Decline in platelet count and long-term post-PCI ischemic events: implication of the intra-aortic balloon pump.

Thrombocytopenia (TC) following a percutaneous coronary intervention (PCI) has been associated not only with hemorrhagic, but also with ischemic outcomes. The purpose of this study was to re-examine the relationship of TC with ischemic events at a 1-year follow-up, and investigate the possible associations.We studied a real-world, unselected population of ischemic patients undergoing PCI, totaling 861 patients-year, and divided into two groups: with TC (delta platelet count ≥25\% from baseline to post-PCI during the hospital admission) and without TC. Compared with patients without TC, patients with TC had a higher and earlier incidence of both hemorrhagic and ischemic events. In them, the use of intra-aortic balloon pump (IABP) was ten-fold higher. In Kaplan-Meier curves assessing the contribution of both TC and IABP to outcome, IABP was a univariate detrimental factor additive to the role of TC. In a forced Cox model, the relative decline (delta) in platelet count (p=0.05) and the use of IABP (p=0.0001) were both associated with ischemic outcomes. After excluding all patients with IABP, the delta platelet count was no longer significantly associated with ischemic outcomes (p=0.66). After excluding all patients with shock and all those who undergone thrombolysis, there was still a relationship (p=0.0042) between the delta platelet count and ischemic events.In this patient population the use of IABP, but not thrombocytopenia per se, is a possible primary cause of worse ischemic outcomes.