Effects of baseline and early acquired thrombocytopaenia on long-term mortality in patients undergoing percutaneous coronary intervention with bivalirudin

Aims: Bivalirudin use as a procedural anticoagulant in patients undergoing percutaneous coronary intervention (PCI) is associated with a lower incidence of thrombocytopaenia compared to other antithrombotic agents. We aimed to evaluate the prognostic impact of baseline thrombocytopaenia and early changes in platelet counts among patients undergoing PCI with exclusive use of bivalirudin. Methods and results: We evaluated 7,505 patients who underwent PCI over a period of eight years. Patients who received unfractionated heparin and glycoprotein IIb/IIIa receptor inhibitors were specifically excluded. Eight hundred and fifty-eight (11.4%) patients had baseline thrombocytopaenia and 451 (6.0%) developed acquired thrombocytopaenia. After adjustment for potential covariates, moderate to severe acquired thrombocytopaenia was the strongest independent predictor (HR 4.34, 95% CI: 2.13-8.84; p<0.001) of in-hospital net adverse clinical events, which included major adverse cardiac events and major bleeding complications. Age, male gender, baseline platelet count and intra-aortic balloon pump (IABP) insertion were independent predictors of in-hospital acquired thrombocytopaenia. After a mean follow-up of 2.6 +/- 1.7 years, moderate to severe baseline thrombocytopaenia (HR 2.42, 95% CI: 1.79-3.29; p<0.001), moderate to severe acquired thrombocytopaenia (HR 2.37, 95% CI: 1.13-4.97; p=0.02) and severe changes in platelet count (> 67 k) were significant predictors of mortality. Conclusions: In patients undergoing PCI with bivalirudin, moderate to severe baseline and acquired thrombocytopaenia along with severe changes in platelet count are associated with higher long-term mortality.