Abstract Body (Do not enter title and authors here): Introduction
Severe atherosclerosis of the aorta poses a significant risk of embolism to peripheral organs. Non-obstructive general angioscopy (NOGA) offers detailed observation of atherosclerosis in the aorta. Cholesterol crystals (CCs) can disperse into the blood from ruptured plaques (RPs) and cause inflammation. However, the relationship between LDL cholesterol levels and the detection rate of CCs from RPs has not been fully elucidated.
Aims
This study aims to evaluate the utility of NOGA in identifying high-risk aortic plaques for CCs detection and to examine the influence of LDL cholesterol levels on this detection rate.
Methods
We investigated 105 consecutive patients with coronary artery disease who underwent NOGA between September 2021 and November 2023. Blood samples were taken from a total of 248 NOGA-derived atheromatous plaques in the infrarenal abdominal aorta. The presence of CCs was assessed using polarized light microscopy and the filter paper rinse method. The CCs detection rates were analyzed by stratifying patients based on LDL cholesterol levels (divided at 100 mg/dL) and the presence of RPs.
Results
The mean age was 67 years; 82.9% were male, 41.0% had diabetes, 99.1% had dyslipidemia, and 78.1% had hypertension. RPs accounted for 52.8％ of the sampling sites, thrombi for 13.3%, yellow plaque for 21.0%, and ulcer and fissure for 12.9%. The overall CCs detection rate was 22.6% (n = 56/248). The detection rates were 1.7% (n = 2/117) in plaques without RPs and 41.2% (n = 54/131) in plaques with RPs (p < 0.001). Among those with LDL levels < 100 mg/dL, the detection rate was 19.3% (n = 41/213), whereas it was 42.9% (n = 15/35) in those with LDL levels ≥ 100 mg/dL (p = 0.039). Specifically, the detection rates were 1.9% (n = 2/104) in plaques without RPs and LDL < 100 mg/dL, 9.1% (n = 1/11) in plaques without RPs and LDL ≥ 100 mg/dL, 36.8% (n = 39/106) in plaques with RPs and LDL < 100 mg/dL, and 58.3% (n = 14/24) in plaques with RPs and LDL ≥ 100 mg/dL (p < 0.001).
Conclusions
Identifying plaque types using NOGA, combined with LDL cholesterol levels, is useful for detecting high-risk aortic plaques prone to CCs. The combination significantly enhances the predictive capability for CCs detection.