Kari Niemelä

　　Coronary artery disease is among leading causes of death in industrialized countries and is expected to become so in emerging countries in the near future.ACS is manifested with acute chest pain with or without persistent ST-segment elevation. The working diagnosis ACS without persistent ST-segment elevation is either non-ST elevation (NSTE) if patient has ST-segment depression and/or T wave abnormalities associated with elevated biomarkers such as troponin.

　　As NSTEMI-ACS is associated with high in-hospital and long-term mortality (long-term even higher than in STEMI) and morbidity, early working diagnosis and risk stratification are essential.

　　The working diagnosis of NSTEMI-ACS should be done quickly at the first medical condition: in the majority of patients clinical symptoms, condition and on 12-lead ECG  findings are enough for the working diagnosis.

　　Optimal medical therapy including antithrombotic treatment should be started immediately and patient should be referred to a hospital with coronary angiography facilities (if feasible). In addition to clinical symptoms, ECG and biomarkers, definite diagnosis and risk stratification can be done based on coronary angiogram and cardiac ultrasound. In a minority of NSTEMI patients additional investigations such as perfusion scintigraphy, MRI and CT are required.

　　In very high risk patients with refractory or recurrent angina in spite of optimal medical treatment, or hemodynamic instability, urgent oronary angiogram should be performed in less than 2 hours after first medical contact. In more stable patients with high risk features coronary angiogram should be performed in less than 24hours, whereas in patients with lessacute risk coronary angiogram should be performed within 3 days.

　　Various scores for risk assessment in NSTE-ACS such as GRACE and TIMI-scores have been developed. Good clinical judgement for risk assessment of individual patient is still "the best tool" available, especially if clinical assessment is done in heart teams involving cardiologist and cardiac surgeon (and also cardiac anesthesiologist when feasible). Instead of various scores, a better additional tool for individual risk assessment should be based on systematic check-list methods