Abstract Body (Do not enter title and authors here): Background:
Atherosclerosis is the most common cause of cardiovascular death. Oxidative stress is related to the initiation and progression of atherosclerosis. However, how oxidative stress affects the progression of atherosclerosis in vivo has not yet been fully investigated. Non-obstructive general angioscopy (NOGA) can meticulously visualize directly aortic atherosclerosis in vivo. The purpose of this study was to evaluate the relationships between oxidative stress and NOGA-derived aortic plaques.

Methods:
We investigated 120 consecutive cases with coronary artery disease evaluated for the aorta by NOGA between July 2021 and February 2024. Atherosclerotic lesions of the aorta were screened using NOGA immediately after coronary arteriography. NOGA examination evaluated the counts of ruptured plaques, chandelier signs, intense yellow plaques, and red thrombi in the aorta. Regarding the number of each plaque, we assessed the proportion of aortic findings detected by NOGA at each vertebral level. Derivatives of reactive oxygen metabolites (d-ROMs) levels as indices of reactive oxygen species production were evaluated.

Results:
The mean age was 66 years, and the median d-ROM value was 289 U.CARR [interquartile range: 251-339]. The d-ROM value was significantly correlated with the proportion of ruptured plaques (r=0.28, p=0.015), but not correlated with the other plaque characteristics. In a multiple linear regression analysis for the proportion of ruptured plaques in the aorta, d-ROMs were one of the independent factors adjusted for age, sex, hypertension, dyslipidemia, and diabetes mellitus (β=0.14, p=0.004).

Conclusion: The value of d-ROMs was related to the proportion of ruptured plaques in the aorta, but not to the proportion of the other plaque characteristics. Oxidative stress may help to elucidate the mechanism for the progression of aortic atherosclerosis.