Risk stratification in acute coronary syndromes (ACS) without ST segment elevation plays an important role in choosing treatment strategy and making further prognosis. We aimed at 1) assessing the usefulness of TIMI Risk Score in risk stratification and prognosis in unselected patients with ACS without ST elevation who underwent early percutaneous revascularization, 2) comparing the frequency of adverse events (death, MI, repeat revascularization in high-risk and moderate-risk patients during 14 days from revascularization, 3) comparing the efficacy of percutaneous revascularization in the high-risk and in the moderate-risk group. High-risk (TIMI Risk Score > or = 5 points) and moderate-risk (TIMI Risk Score 3-4 points) group comprised 324 and 240 patients respectively. High-risk group comprised older patients, fewer men, more diabetics and hypertensive patients. Peripheral vessel disease and prior MI was also more frequent in the high-risk group. More high-risk patients had initial TIMI flow < 3 in target vessel, as well TIMI 3 flow after revascularization was achieved in fewer high-risk patients. During 14-day follow-up the frequency of combined end-point (death, MI, repeat revascularization) was more frequent in the high-risk group (8.95% vs 1.67%). TIMI Risk Score is an easy to use and useful method in risk stratification and prediction of adverse events in patients with ACS without ST segment elevation assigned to early percutaneous intervention in the early post-procedure period.