The Accuracy Of IVUS In Evaluating Ultra-fast CT And CAG

Objective:To study the accuracy assessment of 256- layer CT in evaluating coronary plaque and evaluate in the diagnosis of coronary artery disease.Methods:The patients with CHD from December 2009 to December 2010. 256- layer CT, CAG and IVUS were performed in every patient. IVUS evaluates the diagnostic sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV) and the detection sensitivity (Se) of plaques properties of 256- layer CT. 256 CT and IVUS to MLA, EEMA, the average plaque area, the partial angiostenosis degree, RI, EI carry on the survey according to, further appraises the their relevance.Results:Comparison of segment-based 256- layer CT, IVUS detection: IVUS found 68 lesion segments, 48 non-lesion segments. 256- layer CT found 65 lesion segments, IVUS examination confirmed 63. In 51 non-lesion segments, 47 were confirmed by IVUS. On the segment basis, the sensitivity (Se), specificity (Sp), positive predictive value (PPV), negative predictive value (NPV) of 256-layer CT was 92.6%, 97.9%, 96.9% 92.2%. On the plaque basis, 256- layer detected 16 soft plaque, 18 fibrous plaque, 11 calcified plaques. Compared with IVUS, the sensitivity (Se) were 72.7% and 78.3%, 91.7%. 256 CT to MLA, EEMA, the average plaque area, the partial angiostenosis degree, RI, EI measurements: 6.86±0.86mm2,15.36±2.45mm2,8.48±1.62mm2, 58.6±9.67%,1.06±0.15,0.48±0.09,IVUS measurements: 5.63±0.89mm2, 14.78±2.36 mm2, 9.16±1.83mm2,67.9±9.53%,1.09±0.16,0.52±0.07。The two measurement result p value is smaller than 0.05, the difference has statistics significance. But regarding the judgment mottling's shape, 256 CT and IVUS inspects the r value respectively is 0.79,0.83,0.88,0.68,0.82,0.87.Conclusion:This study shows that: 256-layer spiral CT is a safe, simple and noninvasive method in all coronary, the calcification has a high diagnostic rate,on coronary atherosclerosis higher sensitivity, more specific, the shape of the plaque, and IVUS assessment of the nature of a higher correlation at high risk of coronary artery disease as non-invasive screening and stenting Census , bypass means for postoperative follow-up. But its non-calcified plaque in the reliability of qualitative analysis is still being questioned, while its operators are higher, and requires years of high, has many years experience in inspection of the standard operation. Lower risk during the examination, but for the patient's body are higher, and frequent atrial premature, ventricular premature beats, atrial tachycardia, atrial fibrillation, ventricular tachycardia and other arrhythmias in patients not suitable for selection of the screening method. Part two: The coronary intravascular ultrasound evaluation of coronary angiography to determine the critical nature of disease and the accuracy of plaque.Objective:To study and compare the coronary intravascular ultrasound of the typical symptoms of angina but coronary angiography in patients with negative value.Methods:The hospitalization from December 2009 to December 2010 who diagnosed coronary heart disease but the coronary angiography for 50-70% of patients, do IVUS examination. To patch the plaque morphology,nature, location and degree of stenosis were analyzed, the stent patients discharged were follow-up (myocardial infarction, hospitalization, death, etc.).Results:In this study, qualitative research found that: 49 patients with 59 lesions and eccentric plaques in 42 patients (71.19%), concentric plaque in 17 patients (28.81%), of which 40 cases of soft plaque (67.80%) , fiber-type plaques in 9 cases (15.25%), calcified plaque in 6 cases (10.17%), mixed plaque in 4 cases (6.78%). Found 49 cases of thrombosis in 1 patient (2.04%). Quantitative research found that: IVUS plaque of 59 separate measurements: the average minimum lumen area 4.84±1.13mm2, average EEMA 12.65±3.31mm2, the average plaque area 7.77±2.32mm2, the average minimum lumen diameter 2.22±0.58mm, The average maximum lumen diameter 2.74±0.7mm, mean plaque burden 61.08±11.66%. In which the lesion stent plaque is measured: the average minimum lumen area 3.51±0.94mm2, average EEMA 11.94±2.08mm2, the average plaque area 8.42±1.63mm2, the average minimum lumen diameter 1.87±0.24mm, the average maximum lumen diameter 2.32±0.36mm, the average plaque burden 69.04±7.37%. The average coronary angiography lesion stenosis was 56.4±5.6%, IVUS examination the lesion plaque burden 61.08±11.66%, CAG lesions underestimated the stenosis, the risk of underestimating the disease, the difference was between the two results significance (p = 0.028 <0.05). Conclusion:The clinical symptoms of typical angina pectoris, coronary arteriography lesions underestimated the stenosis, the risk of underestimating the disease, coronary arteriography in patients with critical lesions should be further intravascular ultrasound to accurately assess the degree of stenosis and plaque, for unstable lesions can be down in the IVUS guided PCI treatment, to reduce the rate of plaque rupture lead to serious cardiovascular events.