Growth rate, diameter at rupture, and associated patient characteristics of abdominal aortic aneurysms without an intraluminal thrombus.

Objective: The aim of this study was to provide clinical and prognostic data on the small share of abdominal aortic aneurysms (AAAs) devoid of an intraluminal thrombus (ILT). Methods: Three retrospective samples were studied: electively treated patients (n = 234, growth rates available for n = 158 and an early baseline computed tomography [CT] available for n = 128), patients with rupture (n = 133), and those followed in surveillance (n = 161). Growth rates of electively treated AAAs were calculated based on all measurements preceding surgery. ILT thickness was measured perpendicularly to the aneurysms' centerline and was defined as Results: ILT was absent and minimal in 4.8% and 3.2%, respectively, in the preoperative CT of the electively treated AAAs. Patients with absent/minimal ILT appeared to suffer less cardiovascular burden, but there were no differences in anticoagulation. Absent/minimal ILT was associated with a smaller AAA diameter at baseline ( Conclusions: The absence of ILT is more common in smaller AAAs but is not associated with growth rate. AAAs without ILT seem to rupture at smaller diameters, but ILT absence is not an independent rupture risk factor. Clinical Relevance: The present study analyzed patients with abdominal aortic aneurysms (AAA) that do not develop an intraluminal thrombus (ILT). It was shown that the absence of ILT was associated with smaller maximal diameters in asymptomatic and ruptured AAAs, but there was no difference in growth rate between the groups, and the absence of ILT was not an independent risk factor for rupture. Collectively, these data did not support specific management considerations in patients with AAAs without an ILT.