The Influence On Image Quality And Clinical Application Of 64-Slice Spiral CT Angiography For Coronary Artery

Objective: To investigate the influence on image quality of coronary artery using 64-multi slice computed tomography in detecting coronary artery lesions and analysis the CT appearance of coronary artery and to explore the clinical application . Methods: 64 MSCT coronary angiography were performed in 398 patients. Based on the heart rate we used the different sector scan technique and reconstitution the image in the post-processing workstation. Analysis the 13 segments of coronary in each case. To appreciation the clinical application of 64-slice spiral CT angiography of coronary artery. Results:Image quality was excellent when the heart rate was 50-70 bpm. But if the heart rate change significantly during the scaning, image quality could decline. When the heart rate was more than 70 bpm, two or four sentor recombination image were applied and the superior qulity image could be acquired. 4399 segments of 398 patients were considered to have the diagnostic image quality. Because of motion, severe calcification and completely occlusion, 649 segments could not be sufficiently evaluated. 309 patients were found stenosis. 208 patients have calcification and the calcium score [Agatston score equivalent (ASE)] of 158 patients were less than 400. 42 of the 208 patients had an ASE between 400 to 1000 and 8 patients had an ASE greater than 1000. Compared with Internal Carotid Artery (ICA), the sensitivity, specificity, positive predictive value and negative predictive value of the 64-slice spiral CT angiography of the 32 patients were 95.70%, 90.91%, 82.40%, 97.94%, respectively. 142 segments had stenting in all the 63 patients who were performed percutaneous transluminal stenting. Seven patitents of them were operated the coronary artery bypass grafts and there were 17 bypass artery graft. Conclusion: As a minimally invasive examination, 64-slice spiral CT angiography is a valuable method with higher sensitivity and specificity. It can be an excellent screening test for coronary heart disease and a useful tool to assess the coronary stent patency.