Natural history of the ectatic aorta

To define the natural history of ectatic abdominal aortas and to assess the clinical need for follow-up.

Abdominal aortas were considered ectatic if they were diffusely and irregularly dilated with a diameter less than 3 cm. Ectatic aortas were identified either by AAA screening or as incidental findings. Patients who had only one scan were excluded from the study. Clinical data were analysed.

Two district general hospitals in Wales and England.

116 patients (90 men).

: The median age of patients was 71 years (range 48-90). Co-existing risk factors included hypertension (75), IHD (22), PVD (8), diabetes (3), COAD (14), stroke (5), popliteal aneurysm (1), malignant disease (3) and 4 had a family history of AAA. The median follow-up was 24 months (range 5-72). The median and maximum growth rate of the ectatic aortas were 0.65 and 14.4 mm/year respectively. In three patients the expansion rate was more than 5 mm/year. In 22 patients the ectatic aorta became aneurysmal, reaching a diameter greater than 3 cm. There were no ruptures and no elective repairs. Two deaths occurred due to IHD.

: This study demonstrates that if ectatic aortas do expand they do so very slowly. However, 22 of the 116 (19%) became aneurysmal in a follow-up of two years. Once identified ectatic aortas should be scanned at intervals of three years.