ICD-10-CM > Q00-QA0 > Q20-Q28 > Q23 > Q23.8 Q23.8 Other congenital malformations of aortic and mitral valves Non-Billable/Non-Specific Codes Q23.81Bicuspid aortic valveQ23.82Congenital mitral valve cleft leafletQ23.88Other congenital malformations of aortic and mitral valves