Abstract Background The presence of residual risk in patients with a history of atherosclerotic cardiovascular disease (ASCVD) is a cause of additional cardiovascular events. The aim of this study is to correlate residual cardiovascular risk with the severity of coronary disease. Methods We enrolled 52 patients hospitalized with a diagnosis of acute coronary syndrome from September to October 2023 at the Clinical and Rehabilitation Cardiology of the San Filippo Neri Hospital. All patients were treated with percutaneous and/or surgical coronary revascularization and had a history of ASCVD. Thirty of these patients had a single–vessel coronary disease and 22 had a multivessel coronary disease. We analyzed the main cardiovascular risk factors and the received therapies in both groups. Results Triglyceride levels were significantly higher in the group with a multivessel coronary disease (132.94 ± 65.41 mg/dl vs 94.06 ± 37.63 mg/dl; p=0.01) as well as the levels of glycated hemoglobin (50.91 ± 15.23 mmol/mol vs 42.92 ± 6.65 mmol/mol; p=0.01) and high–sensitivity C–reactive protein (hs–CRP, 1.25 ± 1.48 mg/dl vs 0.65 ± 0.46 mg/dl; p=0.04). We found no significant differences between the two groups for the other main cardiovascular risk factors and the therapies. Conclusions Our data show that higher levels of triglycerides, glycated hemoglobin and hs–CRP, an inflammatory biomarker, are associated with a more extensive coronary disease. This finding suggests that a better metabolic control, in terms of glycated hemoglobin and triglyceride levels, and inflammation could contribute to the reduction of coronary disease extension.