Multidetector computed tomography of a giant left mainstem aneurysm

A 68-year-old gentleman with prior uncomplicated coronary bypass grafting (CABG) presented with worsening symptoms of angina and was accordingly referred for urgent coronary computed tomography angiography (CTA).Coronary CTA showed a dilated left mainstem (LMS) artery measuring 9 mm at the ostium that filled a large aneurysm (51 mm × 52 mm × 49 mm) ( Figure 1A ). The wall of the aneurysm was partly calcified and contained thrombus ( Figure 1B ). The contrast-filled lumen measured 25 mm, with the neck of the aneurysm measuring <4 mm in diameter. The left anterior descending (LAD) artery was attached to the anterosuperior aspect of the aneurysm and was obstructed at its origin while the left internal mammary graft …