Résumé
Purpose The thoracic aortic atherosclerotic plaque is an important source of ischemic stroke embolism in the elderly.This study aims to explore the characteristics of vulnerable plaque of atherosclerosis in the thoracic aorta in the elderly by using three-dimensional multi-contrast magnetic resonancewall imaging technique,so as to actively prevent the occurrence of cardiovascular and cerebrovascular complications.Materials and Methods Fifty-three cases of elderly subjects (＞60 years old) without serious cerebrovascular diseases were recruited in this prospective study.All subjects were divided into A and B groups (60-74 and 75-90 years old).All subjects underwent MRI of multiple contrast sequences of the aortic wall.The thoracic aorta was divided into three segments of ascending aorta,aortic arch and descending aorta,and the characteristics of the atherosclerotic plaque were evaluated.The load characteristics of thoracic aortic atherosclerotic plaques in the elderly were calculated quantitatively,and the compositional characteristics were evaluated qualitatively.Results The incidence of intraplaque hemorrhage in the thoracic aortic atherosclerotic plaque in the elderly was 26.4％ (14/53),and the incidence of lipid nucleus was 94.3％ (50/53).Meanwhile,the maximum wall thickness of three segments of ascending aorta,aortic arch and descending aorta in group B was significantly higher than that in group A [(3.1±0.6) mm vs (3.0±0.4) mm,P＜0.05;(3.2±0.7) mm vs (3.1 ±0.7) mm,P＜0.05;(3.0±0.8) mm vs (2.9±0.7) mm,P＜0.001];the normalized wall index of the three segments in group B was significantly higher than that in group A [(26.9±3.5)％ vs (26.7±2.9)％,P＜0.001;(31.9±5.1)％ vs (31.0±5.1)％,P＜0.001;(34.6±5.0)％ vs (34.1 ±4.6)％,P＜0.001)].Conclusion The incidence of hemorrhage in the atherosclerotic plaque in the thoracic aorta in the elderly is higher,and the plaque load increases with age.Therefore,early screening of vulnerable plaque in the thoracic aorta in the elderly using magnetic resonance wall imaging will be helpful for prevention and treatment of stroke.
Résumé
Objective To evaluate the influences of statin treatment on MR vessel wall imagingobserved characteristics of atherosclerotic plaque in the thoracic aorta of the elderly.Methods Elderly subjects (≥ 60 years) without any serious cerebro-cardiovascular diseases were recruited.Thoracic aorta was imaged on MR scanner for all the subjects.The plaque burden was calculated quantitatively,the composition of plaque in thoracic aorta was evaluated qualitatively,and the contributions of statin treatment to these characteristics were also compared by image interpretation personals.The thoracic aorta was divided into three segments (AAO:ascending aorta;AOA:aortic arch,and DOA:descending aorta)on the imaging.Results Totally 55 recruited subjects had atherosclerotic plaque in thoracic aorta,with 24 subjects receiving statin treatment,and 50 ％ (12/24) male,aged 73.8±6.3 years.The level of LDL C[(2.4±0.7)mmol/L vs.(3.1±0.8)mmol/L(P＜ 0.01)]and total cholesterol[(4.4±0.6)mmol/L vs.(5.1 ±1.0)mmol/L(P＜0.01)]were significantly lower in statin group than in non-statin group.The lumen area,wall area,and total vessel area in all three segments of thoracic aorta were significantly smaller in statin group(all P＜0.05)than in nonstatin group.The average wall thickness in segment of AOA[(2.7±0.3)mm vs.(2.8±0.4)mm(P＜0.01)]and DAO[(2.5±0.4)mm vs.(2.6±0.5)mm(P＜0.01)]were smaller in statin group than in non-statin group.The incidence rate of intraplaque hemorrhage / mural thrombus [6 cases (25.0％) vs.8 cases(25.8 ％)]in thoracic aorta was a little lower in statin group than in non-statin group,with no significant difference(P＞0.05).Conclusions Statin treatment decreases LDL-C level,reduces the burden of atherosclerotic plaque in thoracic aorta,and maintains the atherosclerotic plaque stability.