Non-stenotic echolucent ultrasound-assessed femoral artery plaques are predictive for future cardiovascular events in middle-aged men.

OBJECTIVES

The aim of the present study was to examine the relationship between plaque occurrence, plaque size and plaque echogenicity, assessed by B-mode ultrasound, in the femoral artery and the development of clinical cardiovascular disease.

BACKGROUND

The relationship between carotid atherosclerosis assessed by B-mode ultrasound and cardiovascular disease has been thoroughly investigated. In comparison, the femoral arteries have received much less attention.

METHODS

The femoral artery was examined by high-resolution B-mode ultrasound in 391, 58-year-old men identified by screening in the city of Goteborg, Sweden. Assessment of plaque occurrence, plaque size (no, small, or moderate/large) and plaque characteristics in terms of echogenicity (no, echogenic or echolucent) were performed.

RESULTS

Subjects with a plaque present in the femoral artery at study baseline had a three-fold increase in odds ratio (OR 3.04, 95%, CI 1.24-7.42) for having a cardiovascular event during 6.6 years of follow-up compared to subjects without plaque. After adjustment for cardiovascular risk factors (LDL, triglycerides, systolic blood pressure and smoking) there was a borderline significant association between plaque occurrence and cardiovascular disease (OR = 2.64, p = 0.055). Plaque size could be demonstrated to be associated with cardiovascular events (p = 0.012, for trend). The results also showed that in this group of men, the risk of having a cardiovascular event was to a large extent confined to those with an echolucent plaque at baseline. However, no significant difference in risk prediction was seen between echogenic and echolucent plaques, respectively.

CONCLUSIONS

This is the first study to show that the presence of non-stenotic plaques in the femoral artery in middle-aged men without prior cardiovascular events has a predictive value for future cardiovascular events. The relationship was attenuated by adjustment for traditional cardiovascular risk factors. Data also indicates that plaque echolucency predicts increased risk.