Ivemark syndrome with aortic atresia.

The first case of Ivemark syndrome (agenesis of the spleen with associated congenital heart disease) with aortic valve atresia is reported. No conotruncal abnormalities were noted. This finding brings into question the proposed etiology of this syndrome, namely an unknown teratogenic agent operating coincidently with the development of the spleen and the conotruncal region of the heart. It does not invalidate the flow hypothesis to explain the etiology of aortic atresia.