Background • Coronary atherosclerosis is a serious and progressive condition characterized by the accumulation of plaques, consisting of fat, cholesterol, and other substances, within the arteries that supply blood to the heart. These plaques can harden and narrow the arteries, leading to reduced blood flow to the heart muscle. Objective • The primary objective of this study is to investigate the correlation between specific cardiovascular parameters and intracoronary vascular ultrasound indexes in patients diagnosed with coronary heart disease. This investigation aims to explore the relationships between intracoronary vascular ultrasound measurements and three key cardiovascular parameters: epicardial fat pad thickness, mono-platelet polymer levels, and small dense low-density lipoprotein cholesterol (sdLDL-C) levels. Methods • In this investigation, we applied a comprehensive method to evaluate atherosclerotic plaque characteristics in patients with diverse stages of coronary heart disease (CHD), contrasting these profiles with those of healthy individuals. Our study included 80 acute myocardial infarction (AMI) patients, 145 with unstable angina pectoris (UAP), 175 with stable angina pectoris (SAP), and 100 controls. We utilized intravascular ultrasound (IVUS), an advanced imaging technique that surpasses traditional angiography by providing detailed, high-resolution images of both the coronary artery lumen and wall, including plaque composition. This approach is pivotal for assessing plaque stability, a key factor in the risk of rupture and subsequent cardiovascular events, indicated by features like lipid-rich cores and thin fibrous caps. During IVUS, we quantified parameters such as plaque area, load, and the remodeling index, the latter offering insights into vascular adaptation to plaque buildup. Additionally, we conducted a correlation analysis between IVUS indices and three cardiovascular markers: epicardial fat pad thickness, monocyte-platelet aggregates, and sdLDL-C levels. The goal was to ascertain the predictive value of these markers in tandem with IVUS for determining the stability of coronary artery atherosclerotic plaques. This integrative approach enhances understanding of plaque formation and destabilization, potentially informing more effective CHD prevention and management strategies. Results • Our study revealed distinct variations in key parameters across patient groups with different forms of CHD and healthy controls. Notably, we observed significant differences in gender distribution, hypertension, and diabetes mellitus prevalence among these groups. In terms of IVUS indexes and cardiovascular parameters, the SAP group exhibited markedly different results compared to the AMI and UAP groups. Specifically, the SAP patients showed the lowest values for EMMA, plaque area, plaque burden, reconstruction index, and positive remodeling. Additionally, they exhibited the thickest fibrous caps. In contrast, the AMI and UAP groups presented similar outcomes in these aspects. Regarding the epicardial fat pad thickness, the positive rate of monocyte-platelet aggregates, and the levels of sdLDL-C, there were no significant differences between the AMI and UAP groups. However, these parameters were notably higher in the AMI and UAP groups compared to the SAP group. Crucially, we established a significant correlation between the thickness of the epicardial fat pad, the positive rate of monocyte-platelet aggregates, and the sdLDL-C levels with plaque loading rate and remodeling index. These correlations underscore the potential utility of these parameters as indicators of plaque stability and cardiovascular risk in patients with CHD. This highlights the complexity of atherosclerotic disease progression and underscores the importance of a multifaceted approach to assessing and managing CHD. Conclusion • Our research delineates the critical role of the remodeling index, epicardial fat pad thickness, monocyte-platelet aggregates, and sdLDL-C levels as key prognostic tools for assessing coronary plaque stability in coronary artery disease (CAD). These biomarkers collectively provide an enhanced perspective on plaque vulnerability, an essential aspect in the genesis of acute coronary events. Clinically, these findings are pivotal. They offer a refined approach to CAD management and risk evaluation, allowing for the precise identification of patients at increased risk of plaque rupture, a precursor to acute coronary syndromes. This precision facilitates the adoption of more individualized treatment strategies, focusing on aggressive interventions for high-risk patients and more conservative management for those with stable plaques. [ABSTRACT FROM AUTHOR]