Non-invasive assessment of plaque characteristics in diffuse and focal coronary artery disease; plaque vulnerability and high-risk features.

Recent studies have suggested that focal and diffuse atherosclerotic coronary artery disease (CAD) have significantly different plaque composition, treatment efficacy and outcomes. In this study, we aimed to investigate the plaque characteristics of diffuse and focal lesions in patients who underwent coronary computed tomography angiography (CCTA) for the assessment of obstructive CAD. Patients with CAD-RADS score ≥ 2 were retrospectively reviewed. Plaque characteristics, composition and high-risk features were assessed. Plaques ≥ 20 mm or ≥ 25% of total vessel length were accepted as diffuse lesions and otherwise focal lesions. CCTA-derived plaque features and lesion-oriented cardiac outcomes were compared. After the exclusion of ineligible patients, 597 lesions of 441 patients were evaluated. The mean age of the study population was 55 ± 9,4 years. There were 463 focal lesions and 134 diffuse lesions. Diffuse lesions demonstrated higher calcification (p:0.001). CCTA-derived high-risk features, including spotty calcification (p:0.001), low-attenuation plaque (p: 0.041) and positive remodeling (p: 0.016), were more prevalent in focal disease. In addition, high-risk plaque was also higher in focal lesions(p: 0.022). Moreover, lesions with ≥ 70% plaque burden were significantly higher in focal lesions (p:0.044). Multivariate analysis demonstrated that plaque burden ≥ 70% and CCTA-derived high-risk plaque were independently associated with cardiac outcomes. During the follow-up, lesion-oriented myocardial infarction and revascularization were higher in diffuse disease (p < 0.001 and p:0.015, respectively). Diffuse and focal atherosclerotic lesions demonstrate significant differences regarding plaque vulnerability. Moreover, diffuse plaques have a worse prognosis compared to focal lesions.