Histomorphologic characteristics of abdominal aortic aneurysm samples are similar in abdominal-only vs thoracoabdominal involvement

Abstract

The abdominal aorta is the most frequent site of aneurysm development including mostly localized abdominal aortic aneurysms (AAAs) but also more extensive pathologies like thoracoabdominal aneurysms (TAAAs). This study compares histologic features including inflammation, fibrosis, and angiogenesis in samples from the abdominal aneurysm wall from patients with AAAs (n = 272) and TAAAs (n = 24) after open repair. Both cohorts show a similar pathomorphology and a patient-centered propensity score–matching for age, sex, clinical presentation, maximum diameter, comorbidities, smoking, and basic medication reveals no significant differences for the basic histologic features investigated. These exploratory results can be interpreted towards a possible transferability of basic and translational research results for a nonsurgical treatment of patients with AAAs and TAAAs.

Clinical Relevance

Abdominal aortic aneurysm is by far the most frequent aortic aneurysm—yet basic scientific knowledge is limited, and clinical studies on aneurysm growth abrogation have not shown beneficial effects. Data and understanding on more extensive disease, such as thoracoabdominal aortic aneurysms is even more scarce. This manuscript provides a first hint that pathomechanisms based on histomorphology might be comparable between abdominal aortic aneurysm samples and abdominal wall samples from patients with thoracoabdominal aortic aneurysms in a well-matched propensity-scored analysis. Thus, results from translational research on aneurysm growth alterations could be applicable for both entities.