Echogenicity of carotid atherosclerotic plaques as a predictor of adverse cardiovascular events in patients aged 40–64: prospective study

Abstract

INTRODUCTION: Noninvasive assessment of carotid atherosclerotic plaque (CAP) morphology represents a promising direction, allowing to optimize not only cardiovascular event risk assessment, but also the selection of patients for carotid revascularization. Determination of CAP echogenicity by means of GSM-analysis can be used as part of multiparametric assessment of CAP instability and prediction of adverse cardiovascular events. OBJECTIVE: To assess the predictive value of echogenicity of carotid atherosclerotic plaques in relation to the development of adverse cardiovascular events in patients 40–64 years old. MATERIALS AND METHODS : The study included 191 patients with carotid atherosclerosis aged 40–64 years. All patients underwent duplex scanning of the arteries of the carotid basin with determination of the echogenicity of carotid ASBs. The combined end point (CEP) consisted of the following possible events: nonfatal myocardial infarction or unstable angina, nonfatal stroke, coronary revascularization or peripheral artery revascularization, and death from cardiovascular causes. Data on the onset of CVD were collected during follow-up visits and using medical information systems. Statistics : Data were analyzed using MedCalc software (version 20.216). Frequencies and percentages were used to describe nominal data, and medians and quartiles were used for quantitative data. The Kaplan-Meier survival analysis method was used to estimate the probability of events constituting the combined endpoint. Cox regression analysis was used to estimate the risk of the event and the influence of independent variables on the risk. RESULTS: By correlation analysis, carotid AP echogenicity (GSM) was inversely correlated with BMI (r=-0,355; p<0,0001), waist circumference (r=-0.37; p<0.0001), triglyceride levels (r=-0.163; p=0.027), uric acid (r=-0.188; p=0.028). The duration of the follow-up period was 15.1 (12.2; 22.9) months. Events constituting CEP occurred in 15 (7.85%) patients: nonfatal myocardial infarction in 2 (1.05%) patients, nonfatal stroke in 2 (1.05%) patients, myocardial revascularization in 6 (3.14%) patients, unstable angina in 5 (2.61%) patients. The presence of carotid AP with echogenicity ≤39 conventional units allowed predicting the development of events constituting CEP with sensitivity of 53.3% and specificity of 80.7%. Kaplan-Meier survivalanalysis revealed that cumulative survival of patients with carotid AP with echogenicity ≤39 conventional units was statistically significantly lower compared to patients with carotid ASB with echogenicity >39 conventional units. DISCUSSION: It should be noted that in the presented study, decreased echogenicity of carotid AP was associated with the risk of adverse cardiovascular events only in the simple and sex- and age-adjusted models, but not in the full-adjusted model. It is likely that this may be due to the fact that the echogenicity of CAP is closely related to the cumulative burden of cardiovascular risk factors, which has been shown in earlier studies including. Probably, combined assessment of carotid atherosclerosis burden and morphological features of CAP may be the most promising approach to obtain additional prognostic information in patients with carotid atherosclerosis. CONCLUSION: Among patients with carotid atherosclerosis 40–64 years old, the presence of ACS with echogenicity ≤39 conventional units was associated with a 3.44 (95% CI 1.19–9.91) fold increase in the relative risk of events constituting the combined endpoint after adjusting for sex and age.