Aortic plaque in atrial fibrillation: prevalence, predictors, and thromboembolic implications

Thoracic aortic plaque identified by transesophageal echocardiography heightens the risk of stroke associated with atrial fibrillation (AF). We sought to identify the prevalence, predictors, and implications of aortic plaque in patients with nonvalvular AF.

Thoracic aortic plaque was prospectively sought in 770 persons with AF with the use of transesophageal echocardiography and classified as simple or complex on the basis of thickness >/=4 mm, ulceration, or mobility. Clinical and echocardiographic features of thromboembolism were correlated by multivariate analysis.

Aortic plaque was detected in 57% of the cohort, and complex plaque was detected in 25%. Both were found more frequently in the descending than in the proximal aorta. Potentially etiologic patient characteristics independently associated with complex plaque included advanced age, history of hypertension, diabetes, and past or present tobacco use. Comorbidities associated with aortic plaque were prior thromboembolism, increased pulse pressure, ischemic heart disease, stenosis or sclerosis of the aortic valve, mitral annular calcification (>10%), elevated serum creatinine concentration, spontaneous echo contrast in the left atrium or appendage, and left atrial appendage thrombus. The prevalence of complex plaque in patients aged <70 years with <10% mitral annular calcification, without ischemic heart disease, or without pulse pressure >/=65 mm Hg was 4% (95% CI, 1% to 6%).

Aortic plaque is prevalent in patients with AF and is associated with atherosclerosis risk factors and with left atrial stasis or thrombosis, which are themselves independent stroke risk factors. Since the predominant location of complex plaque was in the descending aorta, the role of aortic plaque as a source of embolism in AF is uncertain.