Analysis of quantitative characteristics and vulnerability of coronary atherosclerotic plaques with distribution of age: based on an out-patient cohort study of coronary CT angiography / 中华放射学杂志

ABSTRACT

Objective:To explore the quantitative characteristics and vulnerable features on coronary CT angiography (CCTA) of coronary atherosclerotic plaques according to age-based classification.Methods:A total of 2 660 consecutive out-patient patients after screening for exclusion criteria were enrolled in a single-center prospective cohort study from January to December of 2017 in Fuwai Hospital. They were all suspected with coronary heart disease and referred for CCTA examinations. There were 5 078 main branches of coronary artery with atherosclerosis plaque. 2 660 patients and 5 078 branches were individually divided into five groups according to their age ≤40, 41-50, 51-60, 61-70, >70-year-old group. The plaque burden and volume percentage of fibrous, lipid and calcified components of plaques were measured, as well as the incidence of CT vulnerable signs. Chi-square test and rank sum test were used to compare the differences of baseline data and the distribution characteristics of the above imaging parameters in different age groups. The correlation between routine risk factors of coronary heart disease and vulnerable plaque of CT was also analyzed by logistic regression.Results:The characteristics of each plaque component of age-based groups were different. The main component of coronary plaques in all age groups was fibrous and the proportion was 83.33% (75.42%, 91.60%), 81.51% (74.44%, 89.07%), 81.85% (74.88%, 88.88%), 82.33% (74.03%, 89.20%),80.99% (73.43%, 88.19%) (χ 2=9.775, P=0.044) respectively. The calcification volume percentage of plaque increased significantly with aging 1.10% (0, 5.53%),1.19% (0, 7.58%), 2.29% (0, 10.45%), 3.97% (0, 14.25%), 6.84% (0.40%, 17.55%) (χ 2=146.719, P<0.001); the lipid volume percentage first increased and then decreased with aging, and the value was highest in 40-50-year-old group 10.94% (5.71%, 19.31%), 12.18% (5.81%, 19.56%), 10.48% (4.83%, 17.14%), 8.14% (3.23%, 15.11%), 7.20% (2.44%, 13.68%) (χ 2=137.470, P<0.001).The results of CT vulnerable characteristics of plaques showed that the incidence of positive remodeling and low-attenuation plaque sign and also the percentage of vulnerable plaque identified by CT all first increased and then decreased, also reached the maximum at 41-50 years old (73.9%, 91.9%, 73.4%) (χ 2=8.678, 3.970, 21.577; P=0.07, P<0.001, P<0.001). Age and sex (male) were independent risk factors for vulnerable plaques identified by CT according to logistic regression analysis. The proportion of CT vulnerable plaques decreased with age (regression coefficient was-0.08). However, the percentage of CT vulnerable plaque in male was higher than that in female patients (regression coefficient was 0.188). Conclusions:The plaque burden increased with age. The lipid volume percentage and incidence of vulnerable plaques identified by CT both increased firstly and then decreased with the highest values in 40-50-year-old group.