Relation of Infra-Renal Abdominal Aortic Calcific Deposits and Cardiovascular Events in Patients With Peripheral Artery Disease

In patients with peripheral artery disease, aortic calcific deposits are a common finding. The aim of this study was to assess the association of infrarenal abdominal aortic calcific deposits with prospective cardiovascular events in patients with peripheral artery disease. A consecutive series of 213 patients who presented for investigation of abdominal aortic aneurysm or intermittent claudication were assessed using computed tomographic angiography. Infrarenal abdominal aortic calcific deposits were estimated using a previously defined highly reproducible semiautomated program. Patients were followed prospectively for a median of 2.8 years (interquartile range 1.7 to 3.6), and cardiovascular events were recorded. Kaplan-Meier and Cox proportional-hazards analysis were used to examine the association of calcific deposits with cardiovascular events. A total of 45 cardiovascular events occurred during follow-up, including nonfatal myocardial infarction (n = 23), coronary revascularization (n = 6), stroke (n = 3), below-knee amputation (n = 2), and cardiovascular death (n = 11). The incidence of cardiovascular events was 21.7%, 33.0%, and 36.9% for patients with mild (<400 mm3), intermediate (400 to 1,700 mm3), and severe (>1,700 mm3) abdominal aortic calcific deposits, respectively (p = 0.039). Calcific deposit volume >400 mm3 (relative risk 2.8, 95% confidence interval 1.2 to 6.6) and coronary artery disease (relative risk 2.8, 95% confidence interval 1.4 to 5.6) were independently associated with increased cardiovascular events during follow-up. In conclusion, abdominal aortic calcific deposits are prognostic for cardiovascular events in patients with peripheral artery disease.