Background: Inflammation markers in the blood may indicate a higher risk of unstable atherosclerosis. Selectins, a group of transmembrane glycoproteins, contribute to inflammation by helping certain blood cells bind to the endothelium. Methods: The study included 100 patients with stable early-onset coronary artery disease (CAD), 75 men (aged 50–54) and 25 women (aged 55–64). Tests performed included biochemical analysis, ultrasound, and Doppler imaging of arteries and peripheral vessels. A biochemical control group of 50 cases without CAD (74% men, average age 48 ± 3.20 years) was also studied. Results: Higher triglyceride levels were strongly linked to elevated plasma E-selectin levels. However, no significant relationship was found between plasma E-selectin levels and biochemical, clinical, radiographic, or echographic measures. Conclusion: Plasma E-selectin levels are not a reliable marker for detecting atherosclerotic plaques or related problems in individuals with stable, well-managed CAD. While E-selectin levels can be measured in clinical labs using immunoassays, they cannot replace standard cardiological and vascular imaging tests for diagnosing cardiac or vascular conditions.