Asymptomatic abdominal aortic aneurysms show histological signs of progression: A quantitative histochemical analysis
Abstract
Paper summarizes results of our prospective non-randomized study in the field of quantitative histopathological analysis of the abdominal aortic aneurysms. We evaluated samples of 65 AAA pateints and 55 corresponding thrombi, also 6 normal abdominal aortas.
Asymptomatic AAAs had more abundant inflammatory infiltrates, lower amounts of PAI-1, a higher number of tPA-positive elements, a greater concentration of VCAM-1 and MMP-2, and a tendency towards decreased collagen content when compared with symptomatic AAAs. Compared with the aneurysmatic aorta, the normal aorta contained less collagen and more elastin, actin, desmin and PAI-1-positive elements; in addition, it was more vascular.
Medium-sized AAAs were the most actin and vimentin rich, and large AAAs were the most vascular. Quantitative microscopy seems to offer a new insight into morphology and pathogenesis of AAA.
Our results indicate the rupture-prone nature of the asymptomatic AAAs and support the need for AAA screening programs.