The ECG was normal at rest but an exercise test revealed ST-segment changes suggestive of cardiac ischaemia. As the patient had experienced the previous invasive cardiac procedures as very painful, he expressed his preference for non-invasive coronary imaging. It was decided to perform multi-slice computed tomography (MSCT, 64-slice CT, Philips Medical Systems). Only mild in-stent and post-stent restenosis of approximately 50 to 60% was seen in the circumflex artery, without further signs of significant stenosis in the epicardial vessels. A slight irregularity at the ostium of the left main coronary artery was appreciated but was not identified as a significant lesion (figures 1A and B). Because of the discrepancy between these findings and the typical symptoms, it was decided to perform coronary angiography. A severe localised stenosis of the left main coronary artery was detected, even after multiple intracoronary injections of 0.4 mg of nitroglycerin (figure 2). In the same session a coronary drug-eluting stent (Cypher, 4.0 diameter, 13 mm length) was inserted in the left main coronary artery after pre-dilatation with a 3.5 balloon. The stenosis in the circumflex artery was treated with a Cypher stent, 23 mm in length and a diameter of 3.0 mm. The initial result was excellent (figure 2) and now, nine months after this procedure, the patient is doing well and is free of anginal symptoms.