We present a 74-year-old female in whom a systolic murmur became trans-systolic during the Valsalva maneuver. The patient had had stable effort angina for 20 years and coronary angiography revealed complete obstruction of the left anterior descending artery in addition to other atherosclerotic lesions. Left ventriculography showed a small apical aneurysm with a narrow orifice. Aorto-coronary bypass surgery and aneurysmectomy were performed; true aneurysm was confirmed pathologically. We conclude that apical aneurysm with a narrow orifice can produce trans-systolic murmur.