Current Status of Diagnostic Process in Asymptomatic Abdominal Aortic Aneurysm in Japan.

This study aimed to investigate the actual detection process and diagnostic methods for asymptomatic abdominal aortic aneurysm (AAA) in a multicenter setting, and to plan an effective screening strategy for asymptomatic AAA. The subjects of this multicenter study were collected in a retrospective manner at 7 facilities. A total of 1894 patients with AAA, including iliac artery aneurysms, who were considered asymptomatic with a confirmed initial diagnosis from January 2018 to December 2022, were collected and reviewed. A total of 1666 patients who were diagnosed with asymptomatic AAA were included [83.9% males, median age of 75 (69-81) years]. Asymptomatic AAAs were frequently diagnosed during examinations for other diseases in 1339 patients (80.4%), whereas health screenings accounted for only 313 (18.8%). Computed tomography (CT) was the most commonly used diagnostic method (n = 1352, 81.2%) compared to abdominal ultrasonography (n = 252, 15.2%). Asymptomatic AAAs are detected incidentally during examinations for other diseases, and there is an urgent need to promote health screening. Most AAAs are diagnosed by CT; nevertheless, we consider that abdominal ultrasonography would be the most appropriate modality for AAA screening because of its reasonable accuracy, noninvasiveness, and low cost.