The MRI Detection Of Carotid Artery Plaque And Coronary Artery Stenosis And Its Relative Study

Objectives:Many clinical investigations and pathological studies have shown the atherosclerosis plaques play an important part in the procession of cardiovascular and cerebrovascular diseases. In recent years, Magnetic Resonance Image(MRI) as a kind of high specificity and sensitivity of noninvasive technique in all techniques which detects the atherosclerosis plaques, was gradually perceived by the public. This study investigated the use of MRI in the detection of carotid plaques and its type, the correlation between carotid artery plaques and coronary artery stenosis, and provided valuable information for the prediction of coronary heart disease (CHD) and guiding treatment. This study was divided into two parts.Methods:Part one:29 patients including 14 men and 15 women with carotid atherosclerosis detected by carotid ultrasound were selected in this investigation. Ranging in age from 42 to 80.With the consents of the patients, all of them accepted carotid artery MRI within one week after the detection by ultrasound. According to the findings of carotid artery MRI and carotid ultrasonography, compared the detection rate of plaque, analyzed the MRI feature and of plaques’ components in magnetic resonance imaging, classified the carotid plaques to eight types according to the American Heart Association carotid classification for MRI, compared various types of plaque distribution in carotid artery bifurcation, internal carotid artery and external carotid artery.Part one:42 patients including 24 men and 18 women detected by coronary artery Computed Tomography Angiography(CTA) were selected in this investigation. Ranging in age from 45 to 86. With the consents of the patients, all of them accepted carotid artery MRI within one week after the detection by CTA. According to the results of coronary artery CTA and carotid artery MRI, to investigate the relationship between the degree of coronary artery stenosis and carotid artery stenosis, the relationship between the degree of carotid artery stenosis and coronary artery stenosis involving vascular count, the correlation between the incidence of carotid plaque and plaque score and the degree of the coronary artery stenosis, and to analyze the various types of coronary plaques distributed in varying degrees of coronary artery stenosis, and to explore the predictive value of vulnerable plaque to coronary artery disease and coronary heart disease.Results:(1) Carotid artery MRI detection specificity and sensitivity of the plaques were 75.0% and 92.0% respectively;(2) 64 atherosclerotic plaques were found in 29 patients. Type Ⅰ-Ⅱ was 21.9%,type Ⅲ(17.%),Ⅳ-Ⅴ(32.8%),Ⅵ(20.3%),Ⅶ(1.6%),Ⅷ(6.2%);(3) The difference was statistically significant of various types of plaque distribution in carotid artery bifurcation, internal carotid artery and external carotid artery(Fisher’s exact test:P= 0.028< 0.05).Most Plaques(65.6%) occured in the bifurcation of carotid artery, and the following Primary sites of Plaques were internal carotid artery(25.0%) and external carotid artery(9.4%);(4) Coronary artery stenosis degree and the degree of carotid stenosis were Positively correlated (rs=0.612,P<0.05), with coronary artery stenosis degree aggravating, the degree of carotid stenosis was also rising;(5) Coronary artery stenosis involving vascular count and carotid artery plaque detection rate were positively correlated (rs=0.587,P<0.05), coronary artery stenosis involving vascular count and carotid artery plaque score were positively correlated (rs =0.735,P<0.05), with the increase of coronary artery stenosis involving vascular count, carotid artery plaque detection rate and plaque score were also rising;(6) Coronary artery stenosis involving vascular count and the degree of carotid stenosis were positively correlated(rs=0.572,P<0.05), with the increase of coronary artery stenosis involving vascular count, the degree of carotid stenosis tended to increase;(7) Mild stenosis group Ⅰ-Ⅱ plaque (non-vulnerable plaques) accounted for 71.4%; moderate stenosis group Ⅰ-Ⅱ type,Ⅲplaque (non-vulnerable plaques) each accounted for 38.7%; severe stenosis in type Ⅳ-Ⅴ,Ⅵ type plaques (vulnerable plaques) each accounted for 37.3%,29.4%.Conclusion:(1) Carotid artery MRI of the specificity and sensitivity of plaque detection rate were high.(2) MRI detection of carotid plaques accordance with carotid artery plaque AHA classification, Ⅰ,Ⅱ,Ⅲ,Ⅳ-Ⅴ,Ⅵ were relatively common, Ⅶ,Ⅷ type were relatively rare.(3) In comparison with external and internal carotid artery, carotid artery plaque was likely to occur in carotid artery bifurcation.(4) There was good correlation between degree of carotid stenosis and coronary artery stenosis degree, moreover, the degree of carotid stenosis and coronary artery stenosis involving vascular count also had a good correlation.(5) With the increase of coronary artery stenosis involving vascular count, carotid artery plaque detection rate and plaque score were also higher.(6) Vulnerable plaque was likely to occur in coronary artery severe stenosis group, the non-vulnerable plaque was likely to occur in coronary artery mild stenosis group and coronary artery moderate stenosis group. The vulnerable plaques had good application value in the prediction and prevention of coronary heart disease.(7) Carotid artery MRI is a non-invasive, idle examination to locate and measure carotid atherosclerosis lesions.