Background. Wellens’ syndrome consists of particular T-wave changes in the precordial leads on ECG accompanied by severe proximal left anterior descending artery stenosis, and is often associated with sudden cardiac death and acute myocardial infarction. It is a pre-infarction state. However, this syndrome is not always an acute process. There are two ECG patterns of Wellens syndrome. Type-A: up sloping ST waves, no or mild ST elevation at the J point and biphasic T waves, with initial positivity and terminal negativity. These T wave findings are present in about 25% of cases. Type-B: symmetrical deeply inverted T waves, in approximately 75% of cases. Both types, R waves preserved in the precordial leads Case report. A 65-year-old male patient, was admitted in the Intensive Care Unit of MCH “Holy Trinity” with Non-STE ACS. Complaining on angina: burning chest pain felt as well in the neck and lower jaw, occurring at mild exertion lasting for ≥40min and relieved by i/v nitrates. Other complains: shortness of breath at mild exertion and fatigue. History: his condition worsened for about 5 days ago while being on a ski resort in Ukraine and felt for the first time angina chest pain lasting about 1h. He was admitted in the ICU of the Regional nonPCI hospital and acute MI diagnose was established, based on a troponin I test – 3,14ng/ml. Because of high costs of the medical care he left the hospital and came back to Moldova by car. During the long trip (5h) he felt several angina episodes, the longest lasting about 40min. ECG at admission: sinus rhythm, normal axis, HR = 76 bpm, up slopping ST segment in V2V4, ST elevation at the J point max 0,5 mm in V3, biphasic T waves in V2-V4 initially positive than negative. Echography: no wall motion abnormality revealed, EF 58%. Serum troponin T – 0.21 ng/ml (0,3ng ml reference limit), CK-MB - 17 U/l (reference limit 24 U/l). Coronary angiography: two-vessel disease, sub occlusive stenosis of proximal LAD (99%), severe on RCA (75-90%). PCI of the culprit lesion with one DES of new generation was performed successfully and the second PCI on RCA scheduled in two weeks (aiming complete revascularization). ECG on the second day following PCI showed no biphasic T-waves in the precordial leads. At 1 month after the complete revascularization, the patient has no symptoms even at intense exertion. Conclusions. It is important to identify the ECG signs of Wellens’ syndrome and provide appropriate treatment in due time, as this ECG pattern is a sign of instability which can evolve any time into an extensive MI with high mortality and disabling rates.