A 47-year-old man presented with orthopnea. He had no infection or, in particular, infectious endocarditis. An echocardiogram and multislice computed tomography scan revealed a left sinus of Valsalva aneurysm (SVA) that had ruptured into the left ventricle, with severe aortic regurgitation. He was diagnosed with ruptured congenital SVA with severe aortic regurgitation and underwent closure of the aneurysmal mouth with a Dacron patch, and concomitant aortic valve replacement. The use of a Dacron patch to close the aneurysmal mouth of a ruptured congenital left SVA has not been reported previously in the medical literature.