Stenosed bicuspid aortic valves in twins.

Hereditary factors may have a part to play in the development of bicuspid aortic valve. This report concerns a pair of identical twins, probably monozygotic, who required aortic valve replacement as a result of aortic stenosis occurring in bicuspid aortic valves. This supports the contention that there may be a genetic influence in the development of bicuspid aortic valve, though environmental factors may be of greater importance.