A thrombus was observed in the left anterior descending coronary artery in a 47 year-old woman who presented with acute anterior myocardial infarction. On a coronary angiogram in the right oblique cranial position, the thrombus appeared as an eccentric, solid and homogeneous mass with a 22 mm maximal length and 1.9 mm maximal diameter. The thrombotic segment and the rest of the coronary tree was free of atherosclerosis. Due to the inappropriate coronary structure and length of the thrombus, coronary angioplasty and/or stent procedures were not performed. The patient refused coronary artery by-pass. She was given the glycoprotein IIb/IIIa inhibitor tirofiban 0.4 mug.kg(-1).min(-1) bolus over 30 minutes followed by 0.1 mug.kg(-1).min(-1) for 24 hours, orally acetylsalicylic acid 300 mg per day, nytroglicerin 40 mg per day and warfarine with INR being in a range of 2-2.5 times. A control coronary angiography performed two months later showed total dissolution of the coronary thrombus and clearance of the culprit vessel.