Asymptomatic popliteal aneurysm: elective operation versus conservative follow-up.

In a retrospective study 42 patients with asymptomatic popliteal artery aneurysm were followed without surgery to identify variables predicting the risk of complications. The mean aneurysm size was 3.1 cm. Abnormal ankle pulses were found in 18 of the 42 limbs in which an asymptomatic popliteal aneurysm was present. Follow-up was complete (mean 6.2 years). Twenty-five patients developed complications at a mean observation time of 18 months. As a result three lost the limb, eight had claudication, two needed a fasciotomy and one had a peroneal nerve palsy. The cumulative risk of developing complications during follow-up was 24 per cent at 1 year, rising to 68 per cent at 5 years. Patients with absent ankle pulses and those already operated on for abdominal aortic aneurysm proved to be especially at risk. Patient survival appeared to be normal for the period of observation. It is concluded that asymptomatic aneurysm of the popliteal artery is a potentially dangerous lesion that may justify elective surgery; it is possible to select those at highest risk.