Surgical Management of Pulmonary Atresia With Ventricular Septal Defect and Major Aortopulmonary Collateral Arteries: Part II—Midline Unifocalization and Unifocalization Revision

A Deep Dive Into Retroesophageal Major Aortopulmonary Collateral Arteries

Background: The anatomy of major aortopulmonary collateral arteries (MAPCAs) can be highly variable with regard to number, anatomic origin, course, and relationship to the native pulmonary arteries. Some MAPCAs travel behind the esophagus (retroesophageal) and bronchus before entering the lung parenchyma. The purpose of this paper was to review the anatomy, physiology, and surgical characteristics of retroesophageal MAPCAs. Methods: This manuscript summarizes the data from a series of three papers that have focused on the subject of retroesophageal MAPCAs from our institution over the past ten years. Results: Two-thirds of patients evaluated had a retroesophageal MAPCA identified at surgery. Retroesophageal major aortopulmonary collateral arteries (REMs) were more common with a left arch (77%) compared with a right arch (53%). Of all REMs evaluated, 83% were single supply, 13% were dual supply with an inadequate connection, and 4% were dual supply with an adequate connection. Based on these findings, 96% of retroesophageal MAPCAs were unifocalized. Follow-up catheterization was performed at a median of 17 months after surgery; 75% of unifocalized MAPCAs were widely patent, 20% were patent but stenotic, and 5% were occluded. Conclusions: The data demonstrate that retroesophageal MAPCAs are relatively common and almost always require unifocalization. At mid-term follow-up, 95% of unifocalized MAPCAs were found to be patent.

Commentary: Should we "keep rollin'" for PA/VSD/MAPCA?

Pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries (PA/VSD/MAPCA) represents an anatomically diverse and technically demanding spectrum of congenital disease. Here, we review a manuscript by Onalan et al. in the Journal of Cardiac Surgery detailing a retrospective, single-center cohort study of patients undergoing unifocalization for PA/VSD/MAPCA via either a pulmonary artery patch augmentation or pericardial roll technique. While they report statistically equivalent outcomes using both techniques, longer follow-up and increased sample size are necessary to determine efficacy and safety.

Midterm fate of unifocalized major aortopulmonary collateral arteries in patients with retroesophageal major aortopulmonary collateral arteries

BACKGROUND

Pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries (MAPCAs) is a relatively rare and complex form of congenital heart disease. Unifocalization of MAPCAs has been advocated by some groups for the treatment of this condition. The purpose of this study was to assess the midterm fate of unifocalized MAPCAs in a cohort of patients with retroesophageal MAPCAs.

METHODS

This was a retrospective review of 37 patients who underwent a unifocalization procedure. All patients in this study had 1 or more retroesophageal MAPCAs, and detailed mapping of the MAPCAs was made based on a combination of the cardiac catheterization and surgical findings.

RESULTS

The 37 patients had a total of 166 MAPCAs, or 4.5 MAPCAs per patient. One hundred twenty-nine (78%) MAPCAs were unifocalized, whereas 37 (22%) were ligated because they were dual supply. Median follow-up was 69 months. At follow-up cardiac catheterization, evaluation of the 129 unifocalized MAPCAs demonstrated that 123 (95%) had antegrade flow, whereas 6 were occluded. For the 123 MAPCAs with antegrade flow, 97 (80%) were widely patent, whereas 26 were stenotic. Thirteen of the 37 patients have subsequently undergone reintervention on MAPCAs that were determined to be stenotic following unifocalization. Seven of these patients had mild disease and had complete resolution with balloon (n = 5) or surgical revision (n = 2). Six patients with moderate or severe disease underwent surgical revision with confirmed resolution in 4 of 6.

CONCLUSIONS

The data demonstrate that the majority of unifocalized MAPCAs remain widely patent following unifocalization. However, one-quarter of unifocalized MAPCAs develop stenoses or occlusion. These results suggest the fate for most unifocalized MAPCAs is favorable but highlight the need for close vigilance.

To Unifocalize or Not to Unifocalize?: A Comparison of Retroesophageal Versus Anterior Collaterals

BACKGROUND

The anatomy of major aortopulmonary collateral arteries (MAPCAs) can be highly variable with regard to number, anatomic origin, course, and relationship to the native pulmonary arteries. Some MAPCAs travel behind the esophagus (retroesophageal) and bronchus before entering the lung parenchyma. This study compared the physiologic and surgical characteristics of retroesophageal vs anterior located MAPCAs.

METHODS

This was a retrospective review of 42 patients who had 1 (n = 36) or 2 (n = 6) retroesophageal MAPCAs. These MAPCAs were then characterized as (1) single supply, meaning no connection to the pulmonary arteries; (2) dual supply, but inadequate connection to the distal pulmonary vascular bed; and (3) dual supply with adequate connection.

RESULTS

The 42 patients presented with 187 MAPCAs, or 4.5 MAPCAs per patient. Of these, 48 MAPCAs were retroesophageal, including 40 that were single supply, 6 were dual supply with inadequate connection, and 2 had dual supply with adequate connection. On the basis of this anatomy and physiology, 96% of retroesophageal MAPCAs were unifocalized. For the 139 anterior MAPCAs, 89 were single supply, 15 were dual supply with inadequate connection, and 35 were dual supply with adequate connection; thus, 75% of anterior MAPCAs were unifocalized (P < .01 compared with retroesophageal MAPCAs).

CONCLUSIONS

The data demonstrate that retroesophageal MAPCAs had very different anatomy and physiology compared with anterior MAPCAs. These results suggest that nearly every retroesophageal MAPCA should be unifocalized to incorporate the lung segments supplied.