双源CT自适应前瞻性心电门控冠状动脉造影:与传统冠状动脉造影对照

Adaptive Prospective ECG Triggering for Dual-source CT Coronary Angiography:Comparison with Conventional Coronary Angiography

目的评价双源CT(DSCT)自适应前瞻性心电门控CT冠状动脉成像(CTCA)对冠状动脉病变诊断的准确性和可行性。资料与方法选取同期行自适应前瞻性心电门控CTCA(扫描前心率低于75次/min)和传统冠状动脉造影(CAG)的30例连续患者作为研究对象。另选取同期行回顾性心电门控CTCA和CAG的45例连续患者作为对照。由两名CT医师和两名造影医师分别对CTCA和CAG图像进行评估。记录CTCA的图像质量和X线剂量。比较自适应前瞻性和回顾性心电门控CTCA的诊断准确性、X线剂量和图像质量。结果对患者冠状动脉病变的诊断,自适应前瞻性和回顾性心电门控CTCA的差异无统计学意义,其敏感性分别为100%、97.4%(P=0.86),特异性分别为66.7%、100%(P=0.65);对分支冠状动脉病变的诊断,两者差异也无统计学意义,其敏感性分别为95.9%、91.1%(P=0.46),特异性分别为97.2%、97.0%(P=0.85);对节段冠状动脉病变的诊断,两者差异同样无统计学意义,其敏感性分别为90.5%、91.2%(P=0.92),特异性分别为98.4%、99.3%(P=0.35)。自适应前瞻性心电门控CTCA的冠状动脉图像质量与回顾性心电门控CTCA类似(3.3±0.5与3.2±0.3;P=0.23)。与回顾性心电门控CTCA比较,自适应前瞻性心电门控CTCA能降低71%的X线剂量[(3.1±1.3)mSv与(10.8±4.6)mSv,P<0.01]。结论在心率低于75次/min、心律稳定的情况下,DSCT自适应前瞻性心电门控CTCA能获得与DSCT回顾性心电门控CTCA相同的诊断准确性,图像质量也无差别,而X线剂量却大大降低。

Objective To evaluate the accuracy and feasibility of dual-source computed tomography coronary angiography （CTCA） using adaptive prospective ECG triggering for the assessment of coronary artery disease （CAD）. Materials and Methods A total of 30 patients with heart rate less than 75 beats per minute underwent adaptive prospective ECG triggering and conventional coronary angiography （Study group） and 45 patients underwent retrospective ECG gating and conventional coronary angiography （Control group）.Two independent radiologists assessed the coronary artery stenosis by CT coronary angiograms,and two independent cardiologists assessed the coronary artery stenosis by conventional angiogra ms.All of them used blinding method.Effective radiation dose was calculated and coronary artery image quality was valuated. Results The diagnostic performance on a per-patient basis between prospective CT angiography and retrospective CT angiography was not significantly different：sensitivity was 100.0%,97.4%,respectively（P=0.86）;specificity was 66.7%,100.0%,respectively （P=0.65）.Similarly,no significant difference was reached on a per-vessel analysis：sensitivity was 95.9%,91.1%,respectively（P=0.46）;specificity was 97.2%,97.0%,respectively （P=0.85）.In the same way no significant difference was reached on a per-segment analysis：sensitivity was 95.9%,91.1%,respectively（P=0.46）;specificity was 97.2%,97.0%,respectively （P=0.85）.Consensus-determined image quality in coronary artery branches was similar between prospective CT angiography and retrospective CT angiography （3.3±0.5 vs 3.2±0.3,respectively;P=0.23）.Calculated effective dose with prospective CT angiography was 71% lower than that with retrospective CT angiography （3.1 msv ±1.3 vs 10.8 msv±4.6,respectively;P〈0.01）. Conclusion Adaptive prospective CT angiography can reduce radiation dose below that of retrospective CT angiography,while maintain the image quality and the ability to assess luminal obstructions in patients with a stable heart rates of less than 75 beats per minute.