Individual acute-phase bleeding and thrombotic risk balance assessment in patients undergoing percutaneous coronary intervention for acute myocardial infarction.

Background: Individualized treatment approach based on pre-procedural precise risk balance assessment between bleeding and thrombosis would be desirable for patients with myocardial infarction (MI) undergoing emergent percutaneous coronary intervention (PCI) in this ultra-short dual antiplatelet therapy era. We aimed to develop and validate a quick thrombosis/bleeding risk-balance assessment tool. Methods: We developed and validated a novel thrombosis/bleeding risk-balance assessment tool using individual patient data from the prospective multicenter MI registry. Individual risks of thrombosis and bleeding within 7 days of the index PCI were estimated using a multinomial logistic regression model. The model was developed in the derivation cohort (4554 patients enrolled during 2003-2009) and validated in the validation cohort (2215 patients during 2010-2014). Results: A total of 6769 patients (66 ± 12 years, 5175 men) were eligible in this analysis. Predictive performance of the multinomial logistic regression models for bleeding and thrombosis assessed by calibration plots was good both in the derivation and validation cohorts. The net predicted probability (NPP) was defined as predicted probability of bleeding event (%) - predicted probability of thrombotic event (%). The NPP successfully stratified patients into those with a higher risk of bleeding than thrombosis and those with a higher risk of thrombosis than bleeding. This finding was consistent between the derivation and validation cohorts. Conclusions: We have established the risk balance assessment model for bleeding and thrombosis. Pre-procedural quick and precise assessment of the risk balance may help a decision making of procedural strategy and antithrombotic regimens in STEMI/non-STEMI patients undergoing PCI.