Male hypoplastic infrarenal aorta and premature atherosclerosis.

Hypoplasia of the abdominal aorta distal to the origin of the renal arteries may be a contributing factor in the development of early atherosclerosis. The abnormal aortic configuration and resultant increased stress forces may account for the localization of the disease to the aortoiliac segment. The increased frequency of single bifurcating lumbar arteries at the L4-L5 level, easily demonstrable on conventional arteriograms, suggests that the aortic hypoplasia may result from excessive fusion of the paired dorsal aortas during embryonic life. Hypoplasia of the infrarenal aorta is present in 9% of females with aortoiliac disease, and it is believed to be uncommon in males. A review of 408 peripheral arteriograms of males revealed 18 cases (4.4%) of hypoplasia of the abdominal aorta. Males with hypoplastic aortas develop symptoms 10 years earlier than those with normal-sized aortas and 10 years later than females with similar narrowing of the distal aorta.