Early Invasive Strategy in Unstable Coronary Artery Disease : Outcome in Relation to Risk Stratification

Abstract: In unstable coronary artery disease (CAD) it still is a matter of debate which patients should undergo early revascularisation. In the FRISC II study (n=2457) an early invasive strategy was, compared to a primarily non-invasive strategy, associated with reduced mortality and myocardial infarction (MI) rates. However, in this heterogeneous group of patients, tools for an appropriate selection to revascularisation are needed.From the FRISC II study we evaluated the prognosis, the angiographic extent of CAD and the effects of an early invasive strategy in relation to risk variables on admission.The occurrence of ST depression and/or elevated levels of Troponin T were associated with a higher risk for death and MI, more severe CAD and also with a reduction of death or MI by the early invasive strategy.Elevated levels of the inflammatory markers C-reactive protein (CRP) and interleukin-6 (Il-6) were associated with a higher mortality but an unchanged MI rate. Elevated levels of Il-6, but not CRP, identified patients with a large reduction of mortality by the invasive strategy.Age ≥ 70 years, male gender, diabetes, previous MI, ST depression and elevated levels of troponin and markers of inflammation were independently associated with an adverse outcome. The FRISC-score was constructed using these 7 variables. At FRISC-score ≥ 5 an early invasive strategy markedly reduced mortality and MI, at FRISC–score 3-4 death/MI was reduced, whereas in patients with a FRISC-score 0-2 neither mortality nor death/MI was influenced.In unstable CAD, a non-invasive strategy seems justified only for patients at low risk, i.e. FRISC score < 2. In patients with intermediate and high risk, i.e. FRISC-score ≥ 3, an early invasive strategy is recommended.