Qualitative and quantitative ultrasound parameters of carotid atherosclerotic plaques in patients with moderate cardiovascular risk according to the SCORE scale: 7-year prospective follow-up study

Abstract

Aim. To assess asymptomatic carotid atherosclerosis in patients with moderate cardiovascular risk over a 7-year prospective follow-up using non-invasive ultrasound markers.Material and methods. Eighty patients (47 men and 33 women) aged 53,1±5,9 years with moderate Systematic Coronary Risk Evaluation (SCORE) level, low-density lipoprotein cholesterol (LDL-C) of 2,7-4,8 mmol/l and asymptomatic hemodynamically insignificant (stenosis <50%) carotid atherosclerosis (CA). Patients underwent CA ultrasound (PHILIPS IU22) at baseline and after 7 years. Plaque number, maximum plaque height, total plaque height, total CA stenosis, visual plaque morphology, gray-scale median (GSM), and intima- media thickness of the right and left common CAs were assessed. All patients were prescribed atorvastatin therapy at a dose of 10-40 mg until a target LDL-С level <2,6 mmol/l was achieved.Results. During the follow-up period, a significant increase was noted in the number of plaques, the maximum and total plaque height, total CA stenosis, and intima- media thickness of the right and left common CAs. An increase in GSM was detected in 79% of plaques on statin therapy. Plaque echoicity increased by 4,90 [0,51; 17,41] (p <0,001) or 7,2% [0,7%; 29%] (p<0,001) over seven years. Regression analysis adjusted for sex and age showed the dependence of GSM changes (ΔGSM) on changes in the LDL-C level (ΔLDL-C) (p=0,049). With a decrease in LDL-C by 1 mmol/l, an increase in average GSM was noted by 5,9 (0,03-11,78). The maximum plaque height increased significantly after 7-year follow-up from 1,80 [1,50; 2,20] to 2,00 [1,63; 2,68] mm (p=0,044). In patients who reached a LDL-C level of 1,8 mmol/l, the maximum plaque height decreased more than in patients who did not reach this level (-0,07 [-0,45; 0,14] mm and 0,20 [-0,05; 0,40] mm, respectively (p=0,028)). Regression analysis adjusted for sex and age did not reveal a relationship between the change of maximum plaque height with ΔLDL-C and Δhigh-density lipoprotein cholesterol, but with LDL-C level after 7 years.Conclusion. Statin therapy in patients with CA stenosis <50% stabilizes the plaques due to echogenicity increase. LDL-C <1,8 mmol/l can lead to a decrease in maximum plaque height.

Keywords

• atherosclerosis
• carotid arteries
• ultrasound
• echogenicity
• gray-scale median
• maximum plaque height
• plaque morphology
• statins