房间隔缺损患者行冠状动脉CTA检查的个性化对比剂注射方案研究

Individual contrast medium injection protocol for coronary CT angiography in atrial septal defect patients

目的:探讨房间隔缺损患者行冠状动脉CTA检查的理想对比剂注射方案。方法:将连续90例拟行介入治疗或外科手术治疗中老年房间隔缺损患者,于术前行冠状动脉CTA检查,依据不同的对比剂注射方案将患者随机分为3组。A组:单期相注射方案(仅注射基础量对比剂,不注射生理盐水);B组:双期相注射方案(先注射基础量对比剂,后以40mL生理盐水冲洗);C组:三期相注射方案(先注射基础量对比剂,后注射30%生理盐水与对比剂的混合物30mL,最后注射40mL生理盐水冲洗)。基础量对比剂按1mL/kg计算,注射流率均为5.0mL/s。比较3组方案CTA图像上冠状动脉及左、右心系统的CT值及房间隔缺损的可评估性。结果:3组患者在平均年龄、体重及心率方面差异无显著性意义。各组患者冠状动脉、升主动脉及左心房、左心室的CT值差异无显著性意义(P>0.05),但各组右心房、右心室及肺动脉的CT值均数大于250HU;此外,B组对比剂用量明显低于其它2组(P<0.05),房间隔缺损量化评分高于C组(P<0.05)。结论:双期注射方案由于对比剂用量减少,利于房间隔缺损评估,因而是房间隔缺损患者行冠状动脉CTA检查的理想的对比剂注射方案。

Objective：To determine the individual protocol for dual-source CT contrast-enhanced cardiac imaging for better visualization of both coronary artery and atrial septal defect. Methods：A total of ninety consecutive patients were in- cluded in this prospective study. Each 30 patients were assigned to use a different contrast protocol., group Ⅰ.. monophasic protocol （basic contrast injection without saline chaser） with a single-syringe injector; group Ⅱ; biphasic protocol （basic contrast injection ＋ saline chaser 40mL） with a dual-syringe injector; group Ⅲ..triphasic protocol （basic contrast media＋ 30% saline-to-contrast medium mixture 30mL＋ saline chaser 40mL） with a dual-syringe injector. The basic contrast media was 1.0ml/kg. Two radiologists rated the visualization of right and left heart structures, coronary artery, ASD （atrial septal defect） and the degree of streak artifacts. One observer performed attenuation measurements of the cardiac chambers and of the coronary arteries. Data were analyzed with one-way analysis of variance and LSD post-hoc multiple comparison proce- dures. Results： Data for 33 men and 57 women （mean age, 58 years） were included, the groups were comparable in mean age, body weight and heart rate. Among the three groups, there were no significant differences for the mean medium atte- nuation of the left heart and the coronary arteries among the three groups （p〉0.05）. Mean contrast medium attenuation in the right heart was significantly （P〈0. 001） higher in the group 3 than the other groups, while the 250HU of CT values were met in right ventriculars and pulmonary arteries in all groups, and the delineation of ASD received significantly higher scores （p〈0.05 LSD test） in the group 2 than the groups 3 for the latter＇s diminished difference in contrast medium con- centration between the left and the right atrium. Conclusion：Biphasic protocol are superior to the other protocols for redu- cing the amount of contrast media and improving the delineation of ASD, and it is advisable for coronary CT angiography with atrial septal defect patients.