Architecture of intraluminal thrombus removed from abdominal aortic aneurysm.

Little is known about architecture of intraluminal thrombus (ILT) in abdominal aortic aneurysm (AAA). We present a 74-year-old woman with AAA and high cardiovascular risk. Scanning electron microscopy of ILT removed during surgery showed that its luminal layer is relatively rich in fibrin fibers forming irregular compact structure with low amounts of erythrocytes and platelets, while abluminal portion is composed of densely packed fibrin with caniculi. The structure of ILT may differ largely among AAA patients contrary to previous findings and may reveal large dense fibrin-rich areas deprived of cells, which impair fibrinolysis and stabilize the thrombus size.