Perioperative changes of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in surgically treated cases of abdominal aortic aneurysm (AAA) were investigated. A retrospective review of 34 patients of AAA who underwent operation was carried out. All patients received cardiac catheterization before the AAA operation. ANP and BNP were measured on the preoperative day, postoperative day (POD) 1 and POD 2, respectively. Twenty-two cases were complicated by ischemic heart disease (IHD). In all cases of AAA, ANP and BNP increased significantly at POD 1 and POD 2. The levels of ANP and BNP in the AAA with IHD group were significantly higher than those in the AAA without IHD group at all points. These results suggest that postoperative care for cardiac overload during the AAA operation is especially needed for patients with IHD.