The pattern of clinical findings and electrocardiography (ECG) changes known as Wellens' syndrome is associated with significant stenosis of the proximal left anterior descending coronary artery. Cases can be classified according to the ECG pattern into type 1 (biphasic T waves) or type 2 (deeply inverted T waves, especially in leads V2 and V3). We present here an unusual case of Wellens' syndrome in which the ECG pattern changed from type 2 to type 1 during observation, and in which the coronary lesion was in the middle rather than the proximal part of the left anterior descending artery.