Arterial Switch Operation — Surgeon’s View #1: Operative Overview

1. Surgical Concept

The arterial switch operation is the definitive anatomic repair for dextro-transposition of the great arteries. The operation restores ventriculoarterial concordance by connecting the morphologic left ventricle to the aorta and the morphologic right ventricle to the pulmonary artery.

The operation is not simply a “switch” of the great arteries. Its technical success depends on three-dimensional reconstruction of the coronary arteries, neo-aorta, and neo-pulmonary artery. Among these, coronary transfer is the defining step. The coronary arteries must be detached from the native aortic root and reimplanted into the neo-aorta without tension, torsion, kinking, ostial narrowing, or compression.

Common coronary transfer methods include the trap-door flap technique and circular buttonhole technique, both of which have been described as practical and reproducible approaches for coronary reimplantation during arterial switch operation [1]. The choice of technique is individualized according to coronary anatomy, spatial relationship of the great arteries, and the final anticipated lie of the coronary arteries after reconstruction.

From the surgeon’s view, the arterial switch operation can be understood as three integrated reconstructions:

1. Coronary transfer
2. Neo-aortic reconstruction
3. Neo-pulmonary artery reconstruction after the Lecompte maneuver

The operation is successful only when all three reconstructions are anatomically aligned and physiologically unobstructed.

2. Establishment of Cardiopulmonary Bypass

After median sternotomy and pericardial exposure, cardiopulmonary bypass is established. Standard cannulation usually includes arterial cannulation of the ascending aorta and venous drainage through the right atrium or bicaval cannulation, depending on whether associated intracardiac repair is required.

The ductus arteriosus is controlled early because it can obscure the operative field and contribute to runoff during bypass. In neonates with d-TGA, the great arteries are usually arranged in an anterior–posterior relationship, with the aorta anterior and the pulmonary artery posterior. This relationship is central to planning the later Lecompte maneuver and coronary transfer.

Key objectives at this stage are:

• Establish safe cardiopulmonary bypass
• Maintain an effective myocardial protection strategy
• Define the relationship between the aorta, pulmonary artery, branch pulmonary arteries, and coronary arteries
• Prepare for safe great artery transection and coronary mobilization

3. PDA Ligation, Aortic Cross-Clamping, and Aortic Transection

The patent ductus arteriosus is ligated and divided. The aorta is cross-clamped, cardioplegia is administered, and the heart is arrested.

The ascending aorta is transected above the sinotubular junction. The transection level must provide adequate tissue for coronary button creation while preserving enough proximal root tissue for later neo-pulmonary reconstruction.

Aortic transection exposes the coronary ostia directly and allows the surgeon to evaluate coronary anatomy before committing to the transfer strategy. This step shifts the operation from exposure to the most important decision-making phase: coronary anatomy analysis.

4. Inspection of Coronary Artery Anatomy

Before creating the coronary buttons, the surgeon must inspect the coronary artery anatomy carefully. Coronary anatomy in d-TGA is variable, and the transfer strategy must be individualized.

The surgeon assesses:

• Location of each coronary ostium
• Relationship between the coronary ostia and commissures
• Proximal coronary course
• Presence of intramural coronary artery
• Single coronary ostium
• Retropulmonary or interarterial coronary course
• Commissural malalignment
• Distance between the coronary origin and intended neo-aortic implantation site
• Height and angle of coronary takeoff

High takeoff, paracommissural origin, and tangential coronary origin increase surgical risk during coronary transfer [2]. These features may create difficulty with button creation, coronary mobilization, and reimplantation geometry. A coronary ostium close to a commissure may also limit the safe margin of aortic wall around the button and increase the risk of commissural distortion or ostial narrowing.

The goal is to predict the final coronary lie before making irreversible incisions.

5. Coronary Button Creation and Mobilization

Each coronary artery is excised as a button of native aortic wall. The button must be large enough to avoid ostial distortion but not so large that it destabilizes the native aortic root or compromises later neo-pulmonary reconstruction.

Mobilization is performed along the proximal coronary course. The purpose is to obtain enough length for tension-free transfer while avoiding injury to the coronary artery, early branches, or surrounding epicardial tissue.

Technical principles include:

• Avoid excessive traction on the coronary artery
• Preserve the natural curvature of the proximal coronary course
• Avoid unnecessary skeletonization
• Maintain adequate adventitial support
• Mobilize enough tissue to prevent tension after neo-aortic reconstruction
• Anticipate the final position after the Lecompte maneuver

Coronary transfer failure may present as ventricular dysfunction, ischemic electrocardiographic changes, difficulty separating from bypass, mitral regurgitation from ischemic papillary muscle dysfunction, or postoperative low cardiac output. Coronary events after arterial switch operation are not rare. In a large series of 1,304 patients, coronary events occurred in 94 patients, or 7.2%, with an early and late distribution and an association with type B or C coronary patterns [3].

6. Main Pulmonary Artery Transection

The main pulmonary artery is transected. The proximal pulmonary root becomes the future neo-aortic root because it remains connected to the left ventricle. The distal pulmonary artery and branch pulmonary arteries are later brought anterior to the neo-aorta during the Lecompte maneuver.

The level of pulmonary artery transection is important. It must allow:

• Adequate length for neo-aortic reconstruction
• Safe coronary implantation into the neo-aortic root
• Sufficient distal pulmonary artery tissue for later neo-pulmonary reconstruction
• Avoidance of branch pulmonary artery tension or distortion

The surgeon must continuously think in three dimensions. The proximal pulmonary root will become systemic outflow, while the distal pulmonary artery will be reconstructed as the right ventricular outflow pathway.

7. Creation of Trap-Door Incisions in the Neo-Aorta

Trap-door incisions are created in the neo-aortic root to receive the coronary buttons. These incisions are made in the proximal pulmonary root, which will become the neo-aorta.

The trap-door technique allows the coronary button to sit into the neo-aortic wall with a favorable angle. It creates a hinged flap that can accommodate the natural direction of the coronary artery and reduce the risk of kinking. Contemporary standardized strategies often use the trap-door method for coronary transfer, combined with preservation of neo-sinotubular junction geometry and extensive branch pulmonary artery mobilization [4].

Key considerations include:

• The trap-door should face the natural direction of the coronary artery
• The incision should avoid excessive rotation of the button
• The implantation site should avoid commissural distortion
• The button should sit without tension after reimplantation
• The neo-aortic wall should not narrow the coronary ostium
• The final coronary takeoff should not be compressed by the reconstructed great arteries

The location of the trap-door incision is determined by coronary anatomy, not by a fixed template.

8. Coronary Artery Reimplantation

The coronary buttons are anastomosed to the neo-aortic root. This is the defining step of the arterial switch operation.

During and after each anastomosis, the surgeon reassesses coronary geometry repeatedly. The coronary artery should leave the neo-aorta smoothly, without acute angulation, twist, stretch, or compression.

Important technical endpoints are:

• Widely patent coronary ostium
• No purse-string narrowing of the button
• No tension on the proximal coronary artery
• No torsion of the button
• No kinking at the coronary takeoff
• No compression after neo-aortic and neo-pulmonary reconstruction
• Preservation of neo-aortic valve competence

Intraoperative imaging can provide additional physiologic information. Abnormal coronary Doppler patterns, particularly flow reversal in the left coronary artery, have been associated with adverse early myocardial events after arterial switch operation [5]. Therefore, the intraoperative assessment should include not only visual inspection of the coronary lie but also evaluation of ventricular function, regional wall motion, electrocardiographic findings, and coronary flow patterns when available.

Even a small imperfection in coronary geometry may have major physiologic consequences because the neonatal myocardium has limited reserve during separation from bypass.

9. Lecompte Maneuver

The distal pulmonary artery and branch pulmonary arteries are brought anterior to the neo-aorta. This is the Lecompte maneuver.

The Lecompte maneuver shortens the course of the reconstructed right ventricular outflow tract and places the pulmonary bifurcation anteriorly. It helps avoid compression of the pulmonary arteries behind the aorta and allows direct reconstruction of the neo-pulmonary pathway.

However, the maneuver can also create branch pulmonary artery distortion if the pulmonary arteries are short, asymmetric, or under tension.

The surgeon must assess:

• Orientation of the pulmonary bifurcation
• Tension on the right and left pulmonary arteries
• Relationship to the reconstructed neo-aorta
• Risk of branch pulmonary artery narrowing
• Relationship between pulmonary artery reconstruction and coronary button position

The Lecompte maneuver should produce a smooth, untwisted pulmonary artery course. The pulmonary arteries should not compress the coronary arteries, and the coronary arteries should not be stretched by the final great artery configuration.

10. Neo-Aortic Patch Augmentation, If Necessary

After coronary transfer, the neo-aortic reconstruction must preserve root geometry, sinotubular junction alignment, and valve competence. Patch augmentation may be used selectively to improve geometry, reduce tension, or compensate for tissue deficiency.

The principle is not simply to close defects, but to reconstruct an anatomically appropriate systemic outflow pathway. Poor geometry may contribute to supravalvar obstruction, valve distortion, coronary compression, or late neo-aortic valve regurgitation.

Contemporary long-term outcome data emphasize that neo-aortic regurgitation, neo-aortic root dilatation, neo-pulmonary stenosis, and coronary artery-related events remain important late concerns after arterial switch operation [4].

11. Neo-Aortic Anastomosis

The proximal neo-aorta is anastomosed to the distal ascending aorta. This establishes the left ventricular outflow tract to the systemic circulation.

At this stage, the surgeon confirms that:

• The neo-aortic anastomosis is not narrowed
• The neo-aorta is not twisted
• The coronary buttons are not under tension
• The coronary courses remain unobstructed
• The neo-aortic valve is not distorted
• The reconstructed ascending aorta has appropriate length and alignment

This step completes the systemic outflow reconstruction. After completion, the surgeon should reassess the coronary arteries because the final neo-aortic geometry may alter the apparent lie of the transferred coronaries.

12. Patch Preparation for Pulmonary Artery Reconstruction

The sites where the coronary buttons were removed from the native aortic root must be reconstructed because this root becomes the neo-pulmonary root.

Patch material is prepared to close the coronary harvest defects and restore continuity of the neo-pulmonary artery. The patch must provide enough tissue to prevent supravalvar neo-pulmonary stenosis and maintain a smooth right ventricular outflow pathway.

Patch design should anticipate the final anterior position of the pulmonary arteries after the Lecompte maneuver.

13. Pulmonary Artery Reconstruction With Patch Augmentation

The coronary button harvest sites are patched, and the neo-pulmonary root is reconstructed. Patch augmentation prevents narrowing at the proximal pulmonary artery and helps create a broad, nonrestrictive right ventricular outflow tract.

Technical goals include:

• Avoid supravalvar pulmonary stenosis
• Avoid pulmonary valve distortion
• Maintain a smooth transition to the branch pulmonary arteries
• Prevent tension at the distal pulmonary artery anastomosis
• Preserve the geometry created by the Lecompte maneuver

Pulmonary artery stenosis is one of the important late morbidities after arterial switch operation. In a 25-year experience including 195 patients, pulmonary stenosis was the most frequent complication and required 45 reinterventions in 26 patients [6]. More recent standardized surgical strategies still report neo-pulmonary stenosis as a relevant late issue, with 15-year freedom from neo-pulmonary stenosis of 77.7% in one single-center series [4].

Therefore, the pulmonary reconstruction must be generous, tension-free, and anatomically aligned.

14. Pulmonary Artery Anastomosis

The reconstructed proximal neo-pulmonary artery is anastomosed to the distal pulmonary artery bifurcation. This completes the right ventricular outflow tract.

The surgeon must ensure that the pulmonary artery pathway is not compressed by the neo-aorta and that neither branch pulmonary artery is stretched, narrowed, or kinked.

The final reconstruction should create two unobstructed outflow pathways:

• Left ventricle → neo-aorta → systemic circulation
• Right ventricle → neo-pulmonary artery → branch pulmonary arteries

The operation is complete only when both pathways are anatomically sound and hemodynamically unobstructed.

15. Separation From Cardiopulmonary Bypass

After rewarming, de-airing, and restoration of cardiac rhythm, the patient is separated from cardiopulmonary bypass.

The immediate assessment focuses on ventricular function, coronary perfusion, valve competence, and outflow tract gradients.

Key findings to evaluate include:

• Left ventricular systolic function
• Right ventricular function
• Regional wall motion abnormalities
• Electrocardiographic evidence of ischemia
• Neo-aortic valve competence
• Neo-pulmonary valve competence
• Neo-aortic anastomotic gradient
• Right ventricular outflow tract and branch pulmonary artery gradients
• Coronary flow concerns
• Bleeding from coronary buttons, great artery anastomoses, or patch suture lines

Difficulty separating from bypass should prompt immediate evaluation for coronary insufficiency, residual intracardiac lesions, ventricular dysfunction, pulmonary hypertension, or technical obstruction.

16. Surgical Priorities and Pitfalls

The arterial switch operation is a geometry-dependent operation. The technical result depends on how the coronary arteries, great arteries, and pulmonary bifurcation lie after reconstruction.

Major pitfalls include:

• Coronary kinking or torsion
• Coronary ostial narrowing
• Excessive coronary tension
• Intramural coronary mismanagement
• Neo-aortic anastomotic narrowing
• Neo-aortic valve distortion
• Supravalvar pulmonary stenosis
• Branch pulmonary artery distortion after the Lecompte maneuver
• Bleeding from coronary buttons or patch reconstruction sites
• Residual VSD or outflow obstruction when associated lesions are present

Complex coronary patterns require deliberate planning. Type B or C coronary patterns have been associated with coronary events after arterial switch operation [3]. High takeoff, paracommissural origin, tangential origin, and intramural coronary course should be recognized before and during the operation because they can significantly alter the transfer strategy [2,4].

The surgeon must repeatedly reassess the final three-dimensional configuration before and after completing each reconstruction.

17. Clinical Significance and Long-Term Surveillance

The arterial switch operation restores the morphologic left ventricle as the systemic ventricle. Compared with atrial switch procedures, it avoids the long-term burden of systemic right ventricular failure and atrial baffle-related complications.

However, long-term surveillance remains essential. Important late issues include:

• Coronary artery stenosis or occlusion
• Neo-aortic root dilatation
• Neo-aortic valve regurgitation
• Supravalvar pulmonary stenosis
• Branch pulmonary artery stenosis
• Residual or recurrent lesions when VSD, arch obstruction, or LVOTO coexist

Late coronary abnormalities may be clinically silent. In one retrospective series, late coronary stenosis or occlusion was identified in 11.3% of patients who underwent coronary evaluation after arterial switch operation, often without preceding symptoms and sometimes after negative noninvasive screening [7]. Earlier angiographic follow-up data also emphasized that asymptomatic patients may still have coronary abnormalities after coronary transfer [8].

Long-term outcome studies also demonstrate that adverse events are not limited to the coronaries. In a contemporary single-center series using a standardized strategy, 15-year freedom from significant neo-aortic regurgitation was 91.7%, freedom from neo-pulmonary stenosis was 77.7%, and freedom from coronary artery-related events was 92.3% [4].

Therefore, the arterial switch operation should be understood not only as a neonatal anatomic repair, but also as the beginning of lifelong surveillance of the coronary arteries, neo-aortic root, neo-aortic valve, and pulmonary artery reconstruction.

18. Core Teaching Message

The arterial switch operation is an anatomic repair built around coronary geometry.

The operation begins with cardiopulmonary bypass and great artery transection, but its success is determined by how safely the coronary arteries are transferred and how smoothly the neo-aortic and neo-pulmonary pathways are reconstructed.

From the surgeon’s view, every step must protect three-dimensional alignment:

1. Coronary perfusion
2. Systemic outflow
3. Pulmonary artery geometry

A technically successful arterial switch operation is not defined by completing the switch alone. It is defined by tension-free coronary transfer, unobstructed ventricular outflow pathways, competent semilunar valves, and pulmonary arteries that remain open and undistorted after the Lecompte maneuver.

References

[1] Baslaim GM. Is preoperative delineation of coronary artery pattern a prerequisite for arterial switch operation? J Card Surg. 2006;21(5):465-470.

[2] Li J, Tulloh RMR, Cook A, Schneider M, Ho SY, Anderson RH. Coronary arterial origins in transposition of the great arteries: factors that affect outcome. A morphological and clinical study. Heart. 2000;83(3):320-325.

[3] Legendre A, Losay J, Touchot-Koné A, Serraf A, Belli E, Piot JD, Lambert V, Capderou A, Planché C. Coronary events after arterial switch operation for transposition of the great arteries. Circulation. 2003;108(Suppl 1):II186-II190.

[4] Lee JH, Kwak JG, Kim ST, Kwon HW, Cho S, Kim WH. Long-term outcomes of standardized strategy in arterial switch operation: an 18-year review in a single center. Korean Circ J. 2026;56:250-265.

[5] Nield LE, Dragulescu A, MacColl C, Manlhiot C, Brun H, McCrindle BW, Kuipers B, Caldarone CA, Miner SES, Mertens L. Coronary artery Doppler patterns are associated with clinical outcomes post-arterial switch operation for transposition of the great arteries. Eur Heart J Cardiovasc Imaging. 2018;19(4):461-468.

[6] Hutter PA, Kreb DL, Mantel SF, Hitchcock JF, Meijboom EJ, Bennink GBWE. Twenty-five years’ experience with the arterial switch operation. J Thorac Cardiovasc Surg. 2002;124(4):790-797.

[7] Tsuda T, Bhat AM, Robinson BW, Baffa JM, Radtke W. Coronary artery problems late after arterial switch operation for transposition of the great arteries. Circ J. 2015;79(11):2372-2379.

[8] Bonnet D, Bonhoeffer P, Piéchaud JF, Aggoun Y, Sidi D, Planché C, Kachaner J. Long-term fate of the coronary arteries after the arterial switch operation in newborns with transposition of the great arteries. Heart. 1996;76(3):274-279.