Popliteal Artery Aneurysm Morphology in Symptomatic and Asymptomatic Patients Undergoing Invasive Treatment

This observational, retrospective, multicentre cohort study aimed to investigate whether a combination of morphological features differs between patients with symptomatic and asymptomatic popliteal artery aneurysms (PAAs) undergoing surgical repair. The secondary aim was to investigate whether morphological features, including arterial angulation, thrombus area, and the degree of runoff, differed.

The cohort included all registered procedures in the National Quality Registry for Vascular Surgery, 2012 - 2020 at two vascular centres. Fifty asymptomatic and 50 symptomatic consecutive patients were included according to the pre-defined sample size. Medical charts and imaging were collected and analysed per protocol. The combination of morphological features included infrapopliteal runoff (0 - 1 or 2 - 3 arteries), artery angulation < or ≥ 45° within the popliteal artery, and intraluminal thrombus area at the maximum diameter level occupying < or ≥ 70% of lumen. Severe morphology was defined as two or more severe features.

The mean age of the cohort was 71 years (standard deviation 9.7), most were men (92%), and the maximum diameter was similar between the groups (27 mm; p = .81). Poor runoff was more prevalent among symptomatic than asymptomatic patients (40% vs. 12%; p = .003). A larger proportion of large thrombus area was observed among symptomatic PAAs (80% vs. 54%; p = .020); 40% of symptomatic cases had occlusion of the artery. Angulation did not differ. Severe morphology was more common in symptomatic patients (44% vs. 18%; p = .005).

The popliteal artery diameter did not differ between asymptomatic and symptomatic PAAs. This challenges the current clinical indication for prophylactic surgery, highlighting that diameter alone is a blunt instrument. The higher proportion of patients with symptomatic PAA and severe combinations of morphological features beyond popliteal diameter indicates that this could be a possible tool when considering PAA repair.