The Marfan syndrome, or arachnodactyly, is a relatively rare familial disorder of unknown etiology characterized by widespread abnormalities of the skeletal, cardiovascular, and ocular systems in which a generalized elastic tissue disorder has often been suggested as the primary fault in pathogenesis.1,2 It will become apparent below that the cardiac lesions of the Marfan syndrome may involve any valve or portion of the heart and aorta, as well as the direct branches of the latter. This syndrome is unusual, but its importance has increased with the era of cardiovascular surgery.1-3 In 1896, Marfan,4 in reporting the first case, described disproportionately long extremities and long spidery fingers. Achard,5 coined the term "arachnodactyly," but the eponym, preferred by some,1 has continued to be used. General abnormalities, including arachnodactyly, relaxation of joints, lack of muscle tone, scant subcutaneous panniculus, dolichocephaly, high arched palate, large misshapen ears, pigeon breast, kyphoscoliosis pectus excavatum, and pes