We measured the time elapsed to move the da Vinci from the left side to the right side. The starting point was the moment that the RIMA harvesting was completed and thoracic hemostasis was confirmed, whereas the end point was the start of the LIMA harvesting.
For preparation for distal anastomosis, the RIMA was passed through the pericardium and led to the left thoracic cavity for distal anastomosis. Through the left thoracotomy in the fourth ICS, distal anastomosis was performed under direct vision (video, http://links.lww.com/INNOV/A104).
Bilateral IMA harvesting by the double-docking technique was performed in ten men and two women with a mean ± SD age of 58.3 ± 10.8 years. The mean ± SD hemoglobin A1c (National Glycohemoglobin Standardization Program) was 7.7 ± 2.2%. The mean ± SD preoperative ejection fraction was 60.0 ± 15.7%. The patients who received dual antiplatelet therapy continued the medication until the operative day.
Bilateral IMA harvesting was successful in all patients. There were no injuries to the BIMA during harvesting, and no dissection was observed in any of the grafts. Total grafts per patient ranged from 2 to 4 (mean ± SD, 2.7 ± 0.5). The graft distribution is listed in Table 1. The median ± SD operation time was 248.8 ± 115.8 minutes. The mean ± SD time required for rotation from the right to left side was 6.5 ± 0.6 minutes. Transposition of the da Vinci was successful in all cases with no mechanical problems. There were no cases of operative death, myocardial infarction, cerebrovascular accident, or renal failure.
Bilateral IMA harvesting from one side of the patient is very difficult and requires an advanced technique. Feasibility of this technique depends heavily on the patient's anatomy because the far side of the IMA must cross the mediastinum. Surgical vision is limited, and sufficient ITA length cannot be harvested. Harvesting is especially difficult in patients who are obese or small or have a funnel chest. In our new approach of the double-docking technique using the da Vinci, BIMA can be harvested easily with acceptable length, and RIMA grafts was used for left anterior descending artery as an in situ graft. As reported previously, using this method, bypass to the target vessel was achieved in every patient. RIMA harvesting from the patient's right side is technically easy because the heart does not project as far into the right thoracic cavity as it does into the left thoracic cavity and surgical vision is not restricted by the heart during the harvest.
Furthermore, during the ITA harvest, insufflation to the thoracic cavity by CO2 is performed. In BIMA harvesting using a unilateral approach, the bilateral lungs are suppressed for oxygenation by pneumothorax. This can lead to high airway pressure, which can cause severe pulmonary complications such as barotrauma. Using the double-docking technique, the CO2 insufflation is performed on one side at a time and the lungs are not simultaneously suppressed. Thus, we noted no respiratory system complications reported in other studies.
Skeletonized IMA harvesting reportedly has better patency for CABG.1 With the use of a high-resolution three-dimensional monitoring system, robotic IMA harvesting can be performed with less damage. The side branch of the IMA was detected clearly, and the IMA was dissected quickly and with little damage. In our study, no postoperative re-exploration was required because the side branch was adequately dissected.
For patients with severe diabetes mellitus, the risk of infection to the mediastinitis by a median sternotomy in harvesting both IMA is considered high. This approach avoids the need for median sternotomy and seems to reduce the risk of mediastinitis. Avoiding a sternotomy also reduced the blood loss. In our study, more than half of the patients were administered two antiplatelet drugs (also known as hybrid therapy), but the procedure was performed safely regardless.
The double-docking technique of the da Vinci is now in the developing stage. Technical advancements are needed to decrease the operation time. The time for rotating the da Vinci will shorten with an acceptable learning curve. In the near future, the transposition time will decrease with the learning curve, and the results will continuously improve. This approach may be an evolutionary step toward total endoscopic coronary bypass surgery.
1. Srivastava S, Gadasalli S, Agusala M, et al. Use of bilateral internal thoracic arteries in CABG through lateral thoracotomy with robotic assistance in 150 patients. Ann Thorac Surg
2. Ishikawa N, Watanabe G, Tomita S, Yamaguchi S, Nishida Y, Iino K. Robot-assisted minimally invasive direct coronary artery bypass grafting. ThoraCAB. Circ J
3. Bonatti J, Schachner T, Bonaros N, et al. Effectiveness and safety of total endoscopic left internal mammary artery bypass graft to the left anterior descending artery. Am J Cardiol
4. Locker C, Schaff HV, Dearani JA, et al. Multiple arterial grafts improve late survival of patients undergoing coronary artery bypass graft surgery: analysis of 8622 patients with multivessel disease. Circulation
5. Halkos ME, Liberman HA, Devireddy C, et al. Early clinical and angiographic outcomes after robotic-assisted coronary artery bypass surgery. J Thorac Cardiovasc Surg
Keywords:©2017 by the International Society for Minimally Invasive Cardiothoracic Surgery
Double-docking technique; Bilateral internal thoracic artery harvesting; Minimally invasive coronary artery bypass grafting; da Vinci surgical system; Robotically-assisted surgery