64排螺旋CT对冠状动脉搭桥术后桥血管评价的研究

Application 64 detector spiral CT to evaluate the graft vessels after coronary artery bypasses graft

目的评价64排螺旋CT对冠状动脉搭桥术后桥血管通畅性的随访价值。方法41例搭桥术后患者,共计104条桥血管,其中42条动脉桥,51条静脉桥,11条序贯桥血管,平均2.54条/例。所有患者在术后3～6个月进行64排螺旋CT桥血管成像检查,扫描范围自胸廓入口至左侧膈肌心尖处,层厚0.5mm,重建间隔1.0mm,螺距1.25,对比剂用量60～70ml,注射速度4ml/s,延迟时间23～28s,对所有病例图像进行后处理重建,包括最大密度投影(MIP)、多平面重建(MPR)、表面遮盖显示(SSD)、容积重建技术(VR)等。对所有图像进行观察,对桥血管通畅性或再狭窄程度进行诊断,特别是近端和远端吻合口的通畅情况。结果所有41例患者顺利完成桥血管64排螺旋CT成像检查,其中94条桥血管显影,10条未见显影血管考虑闭塞,另有10条动脉桥血管可见管壁钙化,5条动脉桥、3条静脉桥以及2条序贯桥血管可见近端或远端吻合口狭窄。结论64排螺旋CT不但能显示冠状动脉桥血管,而且能清晰地显示原始的冠状动脉及吻合口的再狭窄情况,是无创性随访搭桥术后桥血管通畅情况的有效方法。

Objective To investigate the value of 64 detector CT on evaluating the patent of graft vessels following up coronary artery bypass graft （CABG） .Methods Forty-one patients which underwent successfully CABG were performed 64 detector GT 3 - 6 months after procedures. There were totally 104 graft vessels were imaged,including 42 artery vessels, 51 venous vessels and 11 sequential vessels. The scan scale was inlet of thorax to cardiac apex in left diaphragmatic muscle, the protocol was thickness 0.5 mm,interval 1.0 mm, Pitch 1.25,the dose of contrast medium 65 ~ 70 ml, velocity of injection 4 ml/s, delay time 23 - 28 s. All raw images were postprocessed reconstruction with maximum intensity projection （MIP）, multiplanar reconstruction （MPR）, three dimensional surface reconstructions （SSD）, and volume render （VR）. The obtained images were evaluated by two experienced radiologists, to evaluate the patent of graft vessels and restenosis in proximal and distal anastomotic stoma. Results Totally 94 graft vessels in 41 cases were clearly displayed, other 10 graft vessels were considered to be occluded. There were 10 artery graft vessels had calcified, and 5 artery graft vessels,3 venous grafts and 2 sequential grafts had stenosis in proximal or distal anastomotie stoma. Conclusion The 64 detector spiral CT could imaged graft vessels well, also evaluated the native coronary and anastomotie stoma. It provided that it was a good non-invasire method to follow up the patent of graft vessels.