Abstract 9387: The Inverse Association Between the Existence of Coronary Artery Disease and the Progression of Abdominal Aortic Aneurysm

Objectives: The aims of this study are to clarify the relationship among preoperative CAD (coronary artery disease), clinical manifestation of AAA (abdominal aortic aneurysm) and postoperative MACE (major adverse cardiac events). Background: A strong co-existence of CAD and AAA is well-known, however, it remains to be elucidated whether the existence of CAD is associated with the accelerated expansion rate of AAA. Methods: We conducted a retrospective cohort study on 823 consecutive patients receiving the coronary angiography before elective surgical repair for infrarenal fusiform AAA in two hospitals from 2003 through 2009. Ruptured, saccular, traumatic or inflammatory aneurysm were excluded in advance and cases with Marfan syndrome and cases with short followed-up period (<3 months) were also excluded. After exclusion, 665 patients were taken into consideration. All patients were underwent coronary angiography before surgery and their AAA size were followed up by CT scan at least more than 3 times until surgery. Results: The higher rates of postoperative MACE including cardiovascular death, acute coronary syndrome and cerebral infarction were observed in the CAD cases (n=342) compared with non-CAD cases (n=323) by Kaplan-Meier analysis (P=0.038). The initial follow-up size of AAA was 36.8±5.9 mm and the size at surgery was 52.3±10.8 mm. The existence of CAD cases was inversely associated with the accelerated expansion rate of AAA (CAD 3.8±2.1 mm/yr vs. non-CAD 5.0±3.2 mm/yr, HR 0.24, p<0.01). ECG change or asynergy in echocardiography at surgery were not associated with the expansion rate. Otherwise, only ex-smoker was the risk of the expansion rate (HR 1.67, p=0.037). Coronary risk factors except for ex-smoker, and the administration of antihypertensive drugs and statin weren’t significantly associated with the expansion rate. Multiple analyses indicated the same result. Conclusions: Although CAD was the strong risk of MACE after surgical repair for AAA, the counterintuitive inverse association between the existence of CAD and progression of infrarenal AAA was identified. This is the significant study on the relationship between CAD and the expansion rate of AAA.