The Evaluation Of Coronary Plaque Characteristics By Low-dose MSCT

Purpose:Coronary heart disease(CHD) seriously harms human health.Selective coronary arteriography(CAG) remains gold standard to diagnosis of CHD os far.however,the invasive procedure is costly and dangerously.So an alternative non-invasive technique to evaluate coronary arterial stenosis severity would be of great benefit.recently with the technical development and significantly improved image quality,multisice spiral computed tomography(MSCT),as a kind of non-invasive technique,plays a potential role in diagnosis of the patients with CHD.Especially with low-dose CT coronary imaging technologies to carry out, effectively reducing the risk of subjects in patients with radiation.In this study, people with coronary heart disease by comparing the different types of distribution of coronary plaque type of 64-slice spiral CT scan in the low dose group for the clinical diagnosis of coronary heart disease and provide the basis for risk prediction.Materials and Methods:154 patients with suspected coronary artery disease from September 2009 to October 2010 in our hospital undergone CTCA examination, patients were divided into groups with suspected coronary heart disease, chronic stable angina (SAP) and acute coronary syndrome group (ACS). Clinical baseline data between the two groups was not significant. Line 64-slice CT coronary angiography, ECG-gated axial scan taken, according to different parameters in patients with different BMI, tube current 350-800mA low-dose scan program. Using MPR, MIP, CPR and other post-processing techniques of image processing. Coronary atherosclerosis by measuring the CT value of the plaque compared with adjacent tissue, divided into the plaque lipid plaque, fibrous plaque, calcified and mixed plaque, the main coronary artery stenosis and the evaluation of plaque.Results:154 patients select the right coronary artery (RCA), left main coronary artery (LCA), left anterior descending artery (LAD), left-lateral branch (LCX) were used to assess a total of 616 vascular segments (excluding 2 patients without L-branch) of the coronary artery segments, coronary artery image quality, to meet the imaging evaluation of the vascular section 575 (575/616, 93.3%).①154 patients with suspected cases, 59 cases were detected, 10 plaque, fibrous plaque 13, 5 mixed plaque, calcified plaque 5, SAP group were 54 cases of plaque detection 12, fibrous plaque 23, 4 mixed plaque, calcified plaque 10; ACS detected 41 cases of 20 soft plaque, fibrous plaque 14, 20 mixed plaque, calcified plaque 16 a; lipid plaque and mixed plaque and coronary heart disease risk has a significant correlation (P <0.05).②Three groups of coronary patients with 152 plaques were detected, of which 33 suspected group (59 patients), SAP Group 49 (54 patients), ACS Group 70 (41 patients), the number of plaques and coronary heart disease risk has a significant correlation (P <0.05); three groups of patients with atherosclerotic plaques in the coronary are mainly in the LAD; suspected group and SAP group of patients with soft plaque (lipid plaque and fibrous plaque) oriented, ACS group and mixed plaque plaque based.③Non-calcified plaque luminal stenosis caused mainly light - moderate stenosis, severe stenosis and calcification of the major patches of mixed plaque mainly of different patch types in the comparison between the degree of stenosis was statistically significant ( P <0.05).④Check the 154 cases in all patients, the lowest acceptable dose 1.6mSv, the highest dose of 5.8mSv, patients received an average radiation dose 3.3mSv, of which 117 (76%) radiation dose in patients less than 4mSv .Conclusions:64-slice spiral CT with low dose regimens of qualitative analysis of coronary plaque is feasible, It should be used to guide clinical diagnosis and prognosis of follow-up assessment as a coronary risk screening technology.