多层螺旋CT在诊断冠状动脉病变中的应用

目的　评价多层螺旋CT结合回顾性心电门控技术在诊断冠状动脉病变中的应用价值。方法　本组 34例 ,对疑有冠状动脉狭窄的病人分别行多层螺旋CT和导管法冠状动脉造影 ,将 2者结果进行比较 ,分析2者有无一致性以及心率与CT图像质量的关系。结果　右冠状动脉、左冠状动脉前降支、回旋支的最佳显示心电相位窗分别为R波后 5 0 %,5 0 %(6 0 %) ,6 0 %,但图像质量与心率呈明显负相关P <0 0 5 ,当心率低于 75次 /min时可获得最佳图像质量。多层螺旋CT可显示冠状血管近段约 10 0mm的血管情况包括管壁有无斑块及管腔有无狭窄。结论　通过减缓心率可获得符合诊断标准的CT图像 ,结合合适的心电相位窗可有效地减少心动伪影。多层螺旋CT是诊断冠状动脉疾病的有意义的无创检查方法 ,且有广阔的应用前景。

ECG-gated Reconstructed Multi-detector Row CT Coronary Angiography for Coronary Artery Disease

Objective To evaluate the value of electrocardiographical (ECG)-gated retrospective imag4e reconstruction for multi-detector row computed tomographic coronary angiography in diagnosis of coronary artery disease. Methods 34 patients with different heart rates underwent coronary CT angiography and digital subtraction angiography (DSA). The accordance between two methods and the relationships between heart rate, trigger delay and image quality were analyzed. Results Optimal image quality was achieved with a 50% trigger delay for the right coronary artery and 60% for the left circumflex coronary artery. Optimal image quality for the left anterior descending coronary artery was equally obtained at 50% and 60% triggering. A significant negative correlation was observed between heart rate and image quality (P<0.05). The best image quality was achieved when the heart rate was less than 75 beats per minute. Conclusion To achieve high image quality, the heart rate should be sufficiently slowed. Selection of appropriate trigger delay and a decreasing heart rate might be effective to reduce cardiac motion artifacts.