The position and orientation of the heart valves and cusps were investigated in 125 adult and 25 stillborn cadaver hearts in an attempt to establish a reasonably uniform picture of this aspect of cardiac anatomy. The study was prompted by the fact that current textbook figures show wide variation in depicting these structures and also by the fact that the standard nomenclature of the cusps has not been fully accepted by anatomists and cardiologists. There is the additional problem of naming the cusps in congenitally defective hearts. The literature related to cases of great vessel transposition is particularly confusing and the lack of'a uniform figure of the heart valves and disagreement about the cusps adds to the confusion.
The arrangement of the valves and cusps was found to be very uniform in the specimens studied and a standard figure is suggested to replace the variations seen in current texts. It is further suggested that the approved nomenclature of the cusps be followed and several supplemental terms be recognized as accurate. non-ambiguous and useful. particularly in descriptions of the congenitally defective heart.