双源CT在心律失常患者冠状动脉成像中的应用

Application of dual source CT in coronary artery imaging for patients with arrhythmia

目的：探讨双源CT在心律失常患者的冠状动脉成像扫描技术及图像后处理中的应用。方法：452例怀疑冠心病的患者行双源CT冠状动脉成像，心律失常患者70例，其中增强扫描过程中平均心率〉100次／min的患者共56例，房性早搏（atrial premature beat）6例，室性早搏（ventricular oremature beat）5例，房颤（atrial fibrillation）3例。双源CT自动重建最佳收缩期（beat diast）、最佳舒张期（beat syst）图像，若图像欠佳者编辑心电图，然后重建图像．把增强扫描图像行多平面重组（MPR）、最大密度投影（MIP）、容积再现技术（VRT）重建、曲面（CPR）重建。将图像质量分为3级，以美国心脏协会（American heart association，AHA）推荐的解剖分段方法为标准评价冠状动脉各个节段的图像质量。结果：70例心律失常患者经过心电图编辑后冠状动脉重建的最佳时相均为收缩期。共评价561个节段冠状动脉，其中图像质量1级者占87.9％（493／561），图像质量2级者占7.5％（42／561），图像质量3级者占4.6％（26／561）。结论：双源CT用于心律失常患者的冠状动脉成像可获得满意的冠状动脉各节段图像。

Objective：To explore the scanning technique and image quality of coronary artery imaging by dual source CT in patients with arrhythmia. Methods： Four hundred and fifty two cases undergone coronary imaging with dual-source CT. There were 70 cases with arrhythmia, among which there were 56 cases with heart rate more than 100 bprn, 6 cases with atrial premature beat, 5 eases with ventricular oremature beat, and 3 cases with atrial fibrillation. Best diast and syst were reconstructed automatically by dual source CT. Multi-planar reconstruction （MPR）, maximum intensity projection （MIP） and volume rendering （VR） were obtained using contrast enhanced images. The image quality was classified into 3 grades, and coronary seg- ments named according to AHA standard were evaluated. Results： After electrocardiogram edition, the best reconstruction phase was in the systolic phase in 70 patients with high heart rates and arrhythmia. All the 561 coronary segments were evaluated, among which 87.9% （493/561） belonged to the first grade, 7.5% （42/56]） belonged to the second grade, and 4.6% （26/561） belonged to the third grade. Conclusion： Satisfactory coronary artery images can be obtained in patients with high heart rate and arrhythmia by dual source CT.