Familial Incidence of Abdominal Aortic Aneurysms

The rupture of an abdominal aortic aneurysms (AAAs) is associated with a mortality rate exceeding 50%. To reduce this figure it is necessary to increase the frequency of early diagnosis and elective surgery. Screening the general population for occult AAAs has proven cost ineffective. Only by identifying high-risk subgroups will screening programs be improved. The aim of this report was to investigate by ultrasonography the prevalence of previously unknown aortic dilatations among first-degree relatives (parents, siblings, and children) of patients operated on for AAAs.

Ninety-one (52.6%) of the 173 living first degree-relatives of 51 patients who underwent AAA resection were submitted to an aortoiliac ultrasonographic examina tion to establish aortic diameter and morphology. There was at least 1 first-degree relative with an AAA (multiplex family) in 10 families (19.6%) before ultrasound screening. With ultrasound a previously unknown infrarenal aortic dilatation was detected in 14 subjects (9 men/5 women; 10 siblings and 4 children) of 12 different families. Specifically, these aortic dilatations consisted of 10 AAAs (diameters ranged from 2.6 to 4.3 cm) and 4 aortic blebs. These occult aortic dilatations were located in 50% of cases in the lower third of the infrarenal abdominal aorta. The cumulative incidence of multiplex families was 35.3%. This study suggests a familial tendency to have an important etiologic role in the formation of AAAs. Family screening of, above all, male siblings older than forty-five years will help identify occult AAAs and reduce the mortality rates associated with their rupture.