Gulbins H, Reichenspurner H, Becker C, Boehm D H, Knez A, Schmitz C, Bruening R, Haberl R, Reichart B
Department of Cardiac Surgery, University Hospital Grosshadern, Ludwig-Maximilians University Munich, Marchioninistr. 15, D-81366 Munich, Germany.
Heart Surg Forum. 1998;1(2):111-5.
The direct left internal mammary artery (LIMA) bypass to the left anterior descending (LAD) without the use of extracorporal circulation through a small anterolateral thoracotomy has become established among the minimally invasive techniques in cardiac surgery. Technical difficulties may occur in patients with an enlarged left ventricle and subsequent lateral positioning of the LAD, a small LAD, or a small LIMA. We used electron beam tomography (EBT) for preoperative visualization of the topographical structures to seek out patients with potential technical difficulties.
Eighteen patients, mean age 62 +/- 13 years, were entered in this study; in all cases the indication for revascularization was a significant stenosis of the LAD. Preoperatively an ECG-triggered EBT was performed. Following the image acquisition, a three-dimensional reconstruction of the data was performed. The LIMA, LAD, first diagonal branch, and chest wall were stained different colors for better visualization. Surgery was performed using a left anterolateral mini-thoracotomy and through this access, the LIMA was dissected and anastomosed using a stabilizer without the use of extracorporal circulation.
In all but one of the 18 patients who had a preoperative EBT, the minimally invasive direct coronary artery bypass (MIDCAB) procedure was successfully performed using an anterolateral mini-thoracotomy. Based on the results of the EBT, the 5 centimeter incision was done parasternally in six patients, and more laterally (2-4 cm parasternally) in the other eleven cases. In 13 patients the access penetrated the fourth intercostal space; in four cases the fifth intercostal space was used. In one patient EBT revealed a very laterally positioned and diffusely arteriosclerotic LAD so the patient was operated using a median sternotomy, but without the use of extracorporal circulation. In all 18 patients the preoperatively acquired information of the anatomical topography was confirmed intraoperatively. One case without a preoperative EBT had to be converted to a conventional procedure due to a small, intramyocardial LAD and a very small LIMA. Postoperative angiography revealed patent LIMA grafts and uneventful anastomoses.
For minimally invasive direct coronary artery bypass (MIDCAB) the topography of the LIMA, LAD and intercostal spaces is of major importance. Using the ECG-triggered EBT with subsequent three-dimensional reconstruction these relationships can be visualized. This enables an individual planning of the operation and a minimalization of the skin incision.
在心脏外科的微创技术中，经左前外侧小切口不使用体外循环直接将左乳内动脉（LIMA）吻合至左前降支（LAD）已得到确立。对于左心室增大导致LAD侧移、LAD细小或LIMA细小的患者，可能会出现技术困难。我们使用电子束断层扫描（EBT）对局部结构进行术前可视化，以找出存在潜在技术困难的患者。
18例患者纳入本研究，平均年龄62±13岁；所有病例的血运重建指征均为LAD严重狭窄。术前进行心电图触发的EBT检查。图像采集后，对数据进行三维重建。将LIMA、LAD、第一对角支和胸壁染成不同颜色以更好地可视化。手术采用左前外侧小切口，通过该切口，使用稳定器解剖并吻合LIMA，不使用体外循环。
18例术前进行EBT检查的患者中，除1例患者外，其余均成功采用左前外侧小切口完成微创直接冠状动脉旁路移植术（MIDCAB）。根据EBT结果，6例患者在胸骨旁做5厘米切口，另外11例患者切口更偏向外侧（胸骨旁2 - 4厘米）。13例患者的切口穿过第四肋间间隙；4例患者使用第五肋间间隙。1例患者的EBT显示LAD位置非常偏外侧且弥漫性动脉硬化，因此该患者采用正中胸骨切开术进行手术，但未使用体外循环。所有18例患者术中均证实了术前获得的解剖局部信息。1例术前未进行EBT检查的患者因LAD细小且位于心肌内以及LIMA非常细小，不得不转为传统手术。术后血管造影显示LIMA移植物通畅，吻合口良好。
对于微创直接冠状动脉旁路移植术（MIDCAB），LIMA、LAD和肋间间隙的局部解剖结构至关重要。使用心电图触发的EBT并进行后续三维重建，可以可视化这些关系。这使得能够进行个体化的手术规划并最小化皮肤切口。
