Keratoconus and Congential Degenerative Heart Diseases M.Mohammady1, MR.Solaimani1, H.Movahedan2 1- Assistant Professor of Ophathalmology. Medical university of Rafsanjan , Iran 2- Assistant Professor of Ophathalmology. Shiraz Medical university of Rafsanjan , Iran Background: To determine the association of congenital heart disease with keratoconus Material and Methods: In a case – control study, 30 consecutive patients with keratoconus and 30 age and sex matched controls were screened for congenital heart diseases approved by 2-D M. mode echocardiography. Evaluation of association between keratoconus and cardiologic abnormalities was determined by odds ratio. Results: Mitral valve prolapse (M. V. P) was found in 90% of keratoconus group and in 40% of control group (odds ratio = 13.5) Also there was significant association between patent foramen ovale (63,3%, control= 26.6%,odds ratio= 4.75) and tricuspid valve prolapse ( 40%, control= 13.3%,odds ratio = 4.33) and keratoconus. Conclusion: Based on the results, it is suggested that the keratoconus is a nonspecific corneal sign of a systemic collagen metablism disease and further biochemical and clinical studies are required to resolve this question. Keywords: Keratoconus , MVP, PFO, TVP, Congenital heart diseases