冠状动脉搭桥术后磁共振桥血管成像的初步探讨

目的 以ＭＲ成像评价桥血管开通及功能，探讨适用于国人冠状动脉搭桥（ＣＡＢＧ）术后的影像学随访手段，方法 用１．５ＴＭＲ机检查２７例ＣＡＢＧ术后患者的７４支桥血管，行屏气快速场回波（ＦＦＥ）序列扫描观察桥血管的开通。其中１６例４２支桥血管行相位对比磁共振血流成像（ＰＳＭＲＡｆｌｏｗ），得出血流速度和流量曲线，对桥血管的开通进行再评价。结果 本组桥血管ＦＦＥ成像开通率为８９．２％（６６／７４）。以ＰＳ

MR imaging of coronary artery bypass graft: a preliminary study

Objective To study the patency and function of coronary artery bypass grafts(CABG) by magnetic resonance(MR) imaging and to establish a suitable method for followup study after CABG surgery Methods5BZMR imaging was performed with a Toshiba 15T unit in 27 patients with 74 graftsAll patients were examined with a breathhold ECGgated twodimensional fast field echo (FFE) sequence to evaluate the patency of bypass grafts,and among them 16 patients with 42 grafts were further examined with phase shift magnetic renance angiography flow (PSMRAflow) sequence to evaluate the graft patency as well as flow velocity and flow volume vs time Results 66 of the 74 grafts in patients of the present series studied with FFE were patent with a patency rate of 892%The results evaluated both with FFE and PSMRAflow were consistent except two grafts which were patent with FFE but the results with PSMRAflow were uncertain Diastolic perfusion pattern curves were demonstrated in 25 of the 32 grafts Comparing the flow curves of the grafted left internal mammary artery with those of the native right internal mammary artery in 7 patients, the systolic peak velocity value (SPV) of the grafted arteries was significantly lower than that of the ungrafted ones, whereas the diastolic peak velocity value (DPV) and the ratio of DPV to SPV were significantly greater than those of the ungrafed ones 5HZConclusions The FFE and PSMRAflow sequences are efficient in evaluating the patency of the bypass grafts, and obtaining the curves of flow velocity and volume as well therefore, they may offer a reasonable followup study in patients after CABG surgery, although its accuracy should be further evaluated in more patients and compared with other methods