Arterial Switch Operation – Step by Step

The arterial switch operation (ASO) is the definitive correction for neonatal transposition of the great arteries (TGA). Contemporary series report excellent results—near-universal early survival and >95% survival beyond two decades with experienced teams [1,7,8]. Success hinges on precise execution at each stage and, above all, on durable coronary transfer.

1. Preparation and Cannulation

Secure venous and arterial cannulation (typically bicaval/RA and ascending aorta) precedes CPB. In small neonates, plan cannula size and placement to protect venous return and avoid aortic injury; preoperative stabilization (PGE₁, balloon atrial septostomy when needed) and a team checklist streamline initiation [2].

2. Initiation of CPB and Myocardial Protection

After CPB initiation, PDA ligation is performed, the aorta is cross-clamped, and cardioplegia is delivered (blood or crystalloid; antegrade ± retrograde). Neonatal myocardial protection emphasizes careful dosing, temperature strategy, and timely redosing to support postoperative recovery [2].

3. Division of the Aorta

Transect the ascending aorta to expose coronary origins and prepare for transfer. Maintain generous root mobilization to facilitate a tension-free reconstruction [2].

4. Coronary Button Creation and Dissection

Harvest the coronaries as generous “buttons” with a surrounding sinus cuff. Mobilize along the proximal course to gain length while safeguarding intramural segments or single-ostium patterns—key variants that demand tailored strategies and meticulous handling [4].

5. Coronary Transfer (Reimplantation)

Reimplant the buttons into the neo-aortic root (native pulmonary root) with correct orientation and lie. Choose a technique (trap-door, punch, tailored neo-ostia) that minimizes kinking or tension; technical errors here drive early morbidity/mortality and late ischemia, so confirm flow and geometry before proceeding [4].

6. Aortic Anastomosis

Reconstruct the neo-aorta with a wide, tension-free anastomosis and careful hemostasis. Ensure appropriate alignment to avoid twisting or outflow compromise [2].

7. Pulmonary Artery Reconstruction

Prepare the native aortic root as the neo-pulmonary outflow. Patch augmentation may be required to achieve a smooth RVOT with laminar flow; avoid distortion of branch PAs during mobilization [2].

8. Pulmonary Artery Anastomosis (Lecompte Maneuver)

Bring the pulmonary arteries anterior to the neo-aorta (Lecompte maneuver) to prevent great-vessel compression and reduce tension on the PA anastomosis. Patch techniques influence reintervention: redundant pantaloon pericardial patches have been associated with lower neopulmonary reintervention versus some synthetic options [5].

9. Closure of the Atrial Septal Defect

Close the ASD (often intentionally left preoperatively for mixing) to restore complete separation of systemic and pulmonary venous return and finalize anatomic correction [2].

10. Weaning from CPB

Remove the cross-clamp, rewarm, and wean gradually while assessing ventricular function, valve competence, and coronary perfusion. Use TEE, hemodynamics, and lactate to detect residual lesions (coronary insufficiency, neoaortic regurgitation, neopulmonary obstruction) and address them before separation [2,3].

Key Pitfalls and Risk Modifiers

Coronary anatomy (intramural course, single ostium, unusual patterns) increases technical complexity and the risk of ischemia or reintervention; plan transfer strategy accordingly [4].
Pulmonary artery reconstruction technique affects late neopulmonary stenosis; thoughtful patch selection and geometry matter [5].
Complex anatomy or prior PAB and certain morphologies are associated with higher reintervention risk; anticipate surveillance and counsel families appropriately [4].

Expected Outcomes and Follow-up

With current techniques and perioperative care, short-term survival approaches 100%, and long-term survival exceeds 95% in many series; most children achieve excellent functional status [1,7,8]. Late issues include neopulmonary stenosis, neoaortic regurgitation, and coronary complications—necessitating lifelong follow-up with imaging and functional assessment [3,7].

References

[1] Frederick Morfaw, Alvin Leenus, L. Mbuagbaw, L. Anderson, R. Moerloose, et al. Outcomes after corrective surgery for congenital transposition of the great arteries and double outlet right ventricle with subpulmonic ventricular septal defect: A review. Systematic Reviews. 2020. doi:10.1186/s13643-020-01487-3.

[2] C. Fraser. The Neonatal Arterial Switch Operation: How I Teach It. Annals of Thoracic Surgery. 2016. doi:10.1016/j.athoracsur.2016.07.047.

[3] C. Herbst. The Arterial Switch Operation—Not the End of the Story. World Journal for Pediatric & Congenital Heart Surgery. 2021. doi:10.1177/21501351211018202.

[4] Tyson A. Fricke, I. Konstantinov. Arterial Switch Operation: Operative Approach and Important Lessons Learned. Annals of Thoracic Surgery. 2019. doi:10.1016/j.athoracsur.2018.06.002.

[5] Harish S Rudra, C. Mavroudis, C. Backer, S. Kaushal, H. Russell, et al. The arterial switch operation: 25-year experience with 258 patients. Annals of Thoracic Surgery. 2011. doi:10.1016/j.athoracsur.2011.04.101.

[6] A. Castañeda. Arterial Switch Operation for Simple and Complex Transposition of the Great Arteries. The Thoracic and Cardiovascular Surgeon. 1991. doi:10.1055/s-2007-1020009.

[7] Hong-Gook Lim, W. Kim, Jeong Ryul Lee, Yong Jin Kim. Long-term results of the arterial switch operation for simple and complex transposition of the great arteries. European Journal of Cardio-Thoracic Surgery. 2013. doi:10.1093/ejcts/ezs264.

[8] D. Dibardino, Andrew Allison, W. Vaughn, E. Mckenzie, C. Fraser, et al. Current Expectations for Newborns Undergoing the Arterial Switch Operation. Annals of Surgery. 2004. doi:10.1097/01.sla.0000124293.52814.a7.