Objective: Several inflammatory rheumatic diseases are associated with accelerated atherosclerosis. Atherosclerosis may result from systemic and/or local vascular inflammation. The aim of this study was to evaluate the occurrence of chronic inflammatory infiltrates in the aortas of patients with and those without inflammatory rheumatic disease who had undergone coronary artery bypass graft (CABG) surgery, and to assess the relationship between the infiltrates and other factors thought to play a role in atherosclerosis, such as smoking.
Methods: Aortic specimens routinely removed during CABG surgery in 66 consecutive patients with inflammatory rheumatic disease and 51 control patients without inflammatory rheumatic disease were examined by light microscopy for the occurrence, location, and severity of chronic inflammatory infiltrates and atherosclerotic lesions.
Results: Mononuclear cell infiltrates in the inner adventitia (apart from those localized along the epicardium) were more frequent in the group of patients with inflammatory rheumatic disease (47% versus 20%; P = 0.002, odds ratio [OR] OR 3.6, 95% confidence interval [95% CI] 1.6-8.5), and the extent of these infiltrates was greater. Multivariate analyses revealed that the occurrence of mononuclear cell infiltrates was associated with inflammatory rheumatic disease (OR 2.99, P = 0.020) and current smoking (OR 3.93, P = 0.012), and they were observed in 6 of 7 patients with a history of aortic aneurysm. Inflammatory infiltrates in the media were seen only in patients with inflammatory rheumatic disease. The frequency of atherosclerotic lesions, inflammation within the plaques, and epicardial inflammatory infiltrates in the 2 groups was equal.
Conclusion: Among aortic samples collected during CABG surgery, those obtained from patients with inflammatory rheumatic disease had more pronounced chronic inflammatory infiltration in the media and inner adventitia than those obtained from control patients. Current smoking was an independent predictor of chronic inner adventitial infiltrates. The infiltrates may represent an inflammatory process that promotes atherosclerosis and formation of aneurysms.