An integrated clinical approach to predicting the benefit of tirofiban in non-ST elevation acute coronary syndromes: Application of the TIMI risk score for UA/NSTEMI in PRISM-PLUS

Abstract

Aims: We evaluated the TIMI Risk Score for Unstable Angina and Non-ST Elevation Myocardial Infarction for predicting clinical outcomes and the efficacy of tirofiban in non-ST elevation acute coronary syndromes. Methods and Results: Developed in TIMI 11B, the risk score is calculated as the sum of seven presenting characteristics (age ≥65 years, ≥3 cardiac risk factors, documented coronary disease, recent severe angina, ST deviation ≥0.5 mm, elevated cardiac markers, prior aspirin use). The risk score was validated in the PRISM-PLUS database (n=1915) and tested for interaction with the efficacy of tirofiban+heparin vs heparin alone. The risk score revealed an increasing gradient of risk for death, myocardial infarction or recurrent ischaemia at 14 days ranging from 7.7-30.5% (P<0.001). Dichotomized at the median, patients with a score ≥4 derived a greater relative risk reduction with tirofiban (P(Interaction)=0.025). Among patients with normal creatine kinase myocardial bands, the risk score showed a 3.5-fold gradient of risk (P<0.001) and identified a population that derived significant benefit from tirofiban (RR 0.73, P=0.027). Conclusion: The TIMI Risk Score is a simple clinical tool for risk assessment that may aid in the early identification of patients who should be considered for treatment with potent antiplatelet therapy. © 2001 The European Society of Cardiology.