64层螺旋CT在冠状动脉旁路移植术后的诊断价值

目的探讨64层螺旋CT在冠状动脉旁路移植术后诊断桥血管及自体冠状动脉的临床价值。方法对术后2周～8年58例共140条桥血管（动脉桥43条，静脉桥97条）进行64层CT检查，以冠状动脉造影作为金标准，评价显著狭窄（管径狭窄〉50％）的桥血管及〉1．5inin管径的所有自体冠状动脉节段。结果140条桥血管中，38条闭塞，102条开通，CT全部诊断正确。102条开通的桥血管中，18条存在显著性狭窄，CT诊断敏感性100％，特异性95，2％。CT图像能够满足诊断的自体冠状动脉节段占90％。在可评价的冠状动脉节段中，以节段为单位诊断自体冠状动脉显著性狭窄的敏感性84％（87／103）、特异性74％（384／518）。临床正确诊断率为91％（53／58）。结论64层螺旋CT可准确诊断桥血管及自体冠状动脉的显著狭窄，是评价桥血管移植术后的一种无创、可靠的检查方法。

Diagnostic value of 64-slice spiral CT coronary angiography for restenosis after bypass surgery

Objective To assess the accuracy of 64-slice spiral CT in diagnosis of restenosis of coronary artery bypass grafts (CABG) and native coronary arteries in patients after bypass surgery. Methods Fifty-eight patients receiving bypass surgery with totally 140 CABG (43 arterial and 97 venous grafts) were examined using 64-slice spiral CT. CABG and all native coronary arteries with a diameter of >1.5 mm were evaluated for the presence of significant stenoses (>50% diameter reduction) in comparison with the results by coronary angiography as the golden standard. Results Of the 140 CABG examined, 38 were occluded and 104 remained patent, all of which were accurately identified by 64-slice spiral CT. The sensitivity of CT for restenosis detection in the patent graft was 100% (18/18) with a specificity of 95.2% (80/84). In the segmental evaluation of the native coronary arteries, the sensitivity of the CT in identifying significant stenosis in the evaluable segments (90%) was 84% (87/103) with a specificity of 74% (384/518). The accuracy of CT in detecting the presence of at least 1 stenosis in the CABG, distal runoff vessels or nongrafted arteries was 91% (53/58). Conclusion CT allows noninvasive angiographic evaluation of both the native coronary arteries and bypass grafts after bypass surgery.