The relationship of the abdominal aortic aneurysm to the tortuous internal carotid artery. Is there one?

During our investigation of the tortuous internal carotid artery in the presence of atherosclerosis, we noted a 44% incidence of abdominal aortic aneurysm. The incidence of abdominal aortic aneurysm in the adult population is 2% to 4%, and the incidence in a group of patients with carotid atherosclerosis has been reported to be 10%. This supports an association between the tortuous internal carotid artery and the abdominal aortic aneurysm independent of other risk factors. We found no significant difference in sex, age, or other atherosclerotic risk factors between those patients with and those without an abdominal aortic aneurysm. This suggests the possibility of weakness of the arterial wall as a cause of tortuous internal carotid artery and abdominal aortic aneurysm in this group of patients. Better histologic and biochemical definition of this possible weakness is warranted. From a clinical standpoint, we feel that the high association of the two conditions should not be ignored; patients found to have a tortuous internal carotid artery should be investigated and followed up carefully for the presence or subsequent development of aneurysmal degeneration of the aorta.