目的 比较前瞻性心电门控与回 顾性心电门控冠状动脉CT对于小儿先天性 心脏病的诊断价值、图像质量及辐射剂 量。方法 回顾性分析76例经手术证实的 先天性心脏病，所有患者均在本院行MSCT 心脏成像，并记录患者心率、扫描时间、 有效剂量。其中行前瞻性心电门控及回顾 性心电门控MSCT心脏成像各38例。76例患 者均经手术证实并在术前行经胸骨后心脏 超声(TTE)检查。所有心脏CTA图像均由两 名高年资心胸组影像科医师采用双盲法对 图像质量进行评分，评分标准参照五点分 级量化表，评估内容包括整体图像质量， 心腔结构、冠状动脉开口、冠状动脉主干 及主、肺动脉的显示情况。结果 76例患 儿均成功完成扫描，76例患儿的心腔结 构、心外大血管、冠状动脉开口及主干均 能清晰显示，其中前瞻心电门控组患儿的 有效剂量及扫描时间与回顾性心电门控组 相比有显著差异(P<0.05)。前瞻性心电门 控组患儿的平均有效剂量比回顾性心电门 控组减少约76.21%。结论 MSCT前瞻性心 电门控心脏成像在保证图像质量的前提下 辐射剂量明显低于回顾性心电门控，应为 先天性心脏病儿童心脏MSCT检查的首选。

Objective To compare the image quality, dose, diagnostic value of perspective ECG-triggering and restrospective ECG gating coronary artery computed tomography. Methods Retrospective analysis of 76 cases of congenital heart disease, which was confirmed by surgery, all patients in our hospital MSCT cardiac imaging, and record the patients' heart rate, scan time, effective dose. Line of prospective heart switch controlled switch and a retrospective heart MSCT imaging all the 38 cases of heart. 76 patients were confirmed by surgery and preoperative via after sternal cardiac ultrasound (TTE) examination. The image quality of all cardiac CTA images evaluated by two high qualification radiologists by double blind method, classification of quantitative criteria refer to five tables, evaluation content includes the overall image quality, opening heart cavity structure, coronary artery, coronary artery and the mainpulmonary artery showed. Results 76 cases of children were successfully completed the scan, 76 cases of children with cardiac structure, extravascular large blood vessels, coronary artery opening and trunk can clearly show that the prospective ECG gating group of effective dose and scan time And there was significant difference compared with retrospective ECG gated group (P<0.05). The mean effective dose of the prospective ECG gated group was about 76.21% lower than the retrospective ECG gated group. Conclusion MSCT prospective ECG gated cardiac imaging is superior to retrospective ECG under the premise of ensuring image quality. It should be the first choice for MSCT in children with congenital heart disease.