Atherosclerotic coronary artery disease (ACAD) is a major cause of global morbidity and mortality, characterized as an inflammatory process due to damage to blood vessel walls by risk factors like aging, hyperlipidemia, hypertension, smoking, and diabetes. Infectious agents, including Chlamydia pneumoniae (Cpn), Cytomegalovirus (CMV), and Helicobacter pylori (HP), have been implicated in ACAD’s pathophysiology. A study with 56 subjects undergoing coronary artery bypass grafting (CABG) aimed to detect Cpn, CMV, and HP DNA in unaffected artery segments and explore associations with disease progression and inflammation markers. The study found infectious agents’ DNA in 21.4% of samples, HP in eight samples, and CMV and Cpn in four samples each. Significant correlations were observed between HP and overweight or obese subjects, as well as between the presence of infectious agents and inflammation marker values. An association between HP and renal function was also noted. The findings reaffirm previous discoveries of infectious agents in non-clinically affected arteries used as CABG grafts. Correlations identified between the presence of HP, CMV, and Cpn DNA in grafts and several biomarkers of inflammation and obesity emphasize the potential role of these infectious agents in ACAD pathogenesis.