Unguarded tricuspid orifice diagnosed by echocardiography: a clinical study.

Complete absence of tricuspid valve tissue and apparatus with a normal orifice between the right atrium and the right ventricle is defined as "unguarded tricuspid orifice". Very few case report of this anomaly have appeared in the literature. In this article, we present five cases of unguarded tricuspid orifice, isolated or in combination with other anomalies. All patients were males, aged six days to five years; only one case is alive at present. In our opinion, this anomaly is not so infrequent as it is believed to be, and the diagnosis can be made easily with echocardiography if it is kept in mind.