Surgical Technique:

After the completion of robotic-assisted LIMA harvest, robotic trocars are undocked. Peripheral cannulation, either axillary or femoral as planned according to preoperative CT findings, is performed under TEE guidance. Femoral and axillary cannulations are carried out through a 2-3 cm mini-incision with ultrasound guidance.

For axillary cannulation, after the skin incision is made, the pectoralis major muscle is divided and the infraclavicular fat tissue is dissected. The axillary artery is visualised. The artery is encircled with vascular tape proximal to the origin of the thoracoacromial branch and pulled superficially. A purse string suture with 5-0 prolene is placed with a snare on the axillary artery. The guidewire is then advanced through direct puncture of the vessel. The position of the guidewire is confirmed by its visualization inside the ascending or descending thoracic aorta with TEE. After systemic heparinization, direct cannulation of the axillary artery with Seldinger technique under TEE guidance is performed. A pulse oximeter is placed on the cannulated extremity until decannulation. Percutaneous femoral vein cannulation is performed along with axillary artery cannulation.

If femoral cannulation is opted for, it is carried out in the same manner under TEE guidance with a 2-3 cm incision. Cardiopulmonary bypass is then initated and minimally invasive coronary bypass surgery is performed.

 Factors in favour of choosing axillary cannulation:

 Results:

There were no cases of post-operative mortality or stroke in either group. The cross- clamp times were 64.1 ± 16.9 mins in the axillary cannulation group and 80.3 ± 20.8 mins in the femoral cannulation group. Cardiopulmonary bypass times were 153.7 ± 40.3 mins and 155.6 ± 43.5 mins respectively. Mechanical ventilation times were 4.2 ± 1.9 hours and 5.3 ± 3.6 hours respectively in the axillary and femoral cannulation groups. The ICU stay was 19.7 ± 4.7 hours and 19.9 ± 5.4 hours; and the hospital stay was 7.3 ± 2.5 days and 7.6 ± 2.7 days, respectively. No complications including hematomas, cannulation site infections, emboli, dissection, neurovascular injury or brachial plexus injuries were observed in any of the patients in either groups. No other complications were encountered in the axillary cannulation group. One patient (2.6%) in the femoral cannulation group was reoperated for mediastinal bleeding. No other complications were encountered in patients with femoral artery cannulation except for seromas at the cannulation site in 3 (7.7%) of the patients, and this low rate of complications was attributed to the elaborative preoperative investigation of patients with severe calcification and the preference of axillary artery cannulation if atherosclerotic disease is present.

Conclusion: