Aim: Knowledge of subclinical plaque morphology and plaque distribution in the aorta in vivo remains unclear. This study aimed to increase the body of knowledge in this area.
Methods: We enrolled 37 consecutive patients with stable angina pectoris patients who underwent non-obstructive angioscopy for both the coronary artery and aorta immediately after percutaneous coronary intervention. We evaluated the presence of aortic plaques and the distribution of plaque instability. Patients were allocated into two groups according to the number of vulnerable plaques in whole aorta (a low [0-11] and high [≥ 12] group). We evaluated the relationships between the two groups in terms of cardiovascular risk factors.
Results: Aortic plaques were identified using non-obstructive angioscopy in all patients, and the greatest number of plaques was found at the infrarenal abdominal aorta (IAA) (the aortic arch, the descending thoracic aorta, the suprarenal abdominal aorta, the IAA, and common iliac artery; 65%, 76%, 65%, 95%, and 49%, respectively; p＜0.001). The maximum yellow grade, and the number of intense yellow plaques, ruptured plaques, and thrombi were highest at the IAA (p＜0.001). The prevalence of diabetes mellitus and peripheral arterial disease was higher in the high vulnerable plaque group (83.3% vs. 40.0%, p=0.010, 50.0% vs. 8.0%, p=0.005, respectively).
Conclusions: Aortic atherosclerosis was the most severe at the IAA, and aortic plaque vulnerability and distribution were associated with the prevalence of diabetes mellitus and peripheral artery disease in patients with stable angina pectoris. Non-obstructive angioscopy may identify patients at high risk of future aortic events.
Keywords: Aortic angioscopy; Aortic plaque distribution; Atheromatous plaque; Atherosclerotic risk factors; Plaque morphology.