Objective--Coronary plaque instability causes myocardial infarction (MI). Angiographic lesions with such instability are complex lesions. Complex carotid plaques were reported to be prevalent in unstable angina. We investigated associations between coronary plaque instability, such as MI and angiographic complex coronary lesions, and aortic plaques.

Methods and Results--Aortic MRI was performed in 146 patients undergoing coronary angiography, of whom 108 had coronary artery disease (CAD) and 44 also had MI. Prevalence of plaques in thoracic and abdominal aortas was higher in patients with than without CAD (73% and 94% versus 32% and 79%), but it was similar in CAD patients with and without MI. Notably, complex plaques in abdominal aorta were more prevalent in CAD patients with than without MI (36% versus 14%; P<0.025). In multivariate analysis, abdominal complex plaques were associated with MI (odds ratio [OR], 4.5; 95% CI, 1.5 to 13.8). Among patients without MI, thoracic and abdominal complex plaques were more prevalent in patients with than without complex coronary lesions (22% and 33% versus 2% and 7%; P<0.05). Abdominal complex plaques were also associated with complex coronary lesions (OR, 9.8; 95% CI, 1.1 to 85.9).

Conclusion--Complex plaques in abdominal aorta were associated with MI and complex coronary lesions, suggesting a link between coronary and aortic plaque instability.