Objective: Plaque instability is recognized as a multivessel phenomenon related to inflammation. This study examined if the morphology of femoral plaques was related to that of carotid plaques.
Methods: The echogenicity of femoral and carotid plaques of 102 patients with peripheral artery disease (PAD) was studied and classified as echolucent or echorich according to the gray-scale median (GSM) value, which was 53.6 for femoral plaques and 55.2 for carotid plaques. Serum C-reactive protein (CRP) levels and neutrophil count were also measured.
Results: Echolucent carotid plaques were more frequent in patients with echolucent than in those with echorich femoral plaques (55.8% vs 32.0%; P < .01). At multivariate analysis, femoral GSM lower than the median was the only significant predictor of echolucent carotid plaques (odds ratio [OR], 3.87; 95% confidence interval [CI], 1.53-9.83). Patients with echolucent femoral plaques had higher serum CRP levels (P < .01) and a higher neutrophil count (P = .029) than patients with echorich femoral plaques. However, univariate analysis showed that neutrophil count (OR, 3.48; 95% CI, 1.23-9.85) but not hs-CRP was associated with echolucent carotid plaques. At multivariate analysis, neutrophil count exceeding the median remained associated with echolucent carotid plaques (OR, 5.71; 95% CI, 1.37-23.85), whereas the association between femoral and carotid echolucency was attenuated (OR, 3.75; 95% CI, 0.98-4.43).
Conclusions: In PAD, the presence of echolucent femoral plaques is associated with a greater prevalence of echolucent carotid plaques, probably as a consequence of a more pronounced inflammatory profile. This confirms and extends the finding that plaque echolucency is a multivessel phenomenon. Prospective studies are needed to assess whether carotid screening in PAD patients might contribute to improving clinical decision-making.