Basic Concepts and Insights into Aortopulmonary Collateral Arteries in Congenital Heart Diseases

Aortopulmonary collateral arteries are persistent embryological vessels supplying lung parenchyma in various cardiopulmonary diseases with underlying pulmonary hypoperfusion. Their identification and mapping are important because of associated clinical implications and tendency to affect the surgical outcome. This article describes the embryological development and clinical relevance of aortopulmonary collaterals in various congenital cardiopulmonary conditions, along with the significance for treatment planning. Roles, strength, and shortcomings of the various imaging options and image-guided interventions are discussed, with a focus on presurgical planning and preparation, as well as postsurgical management.

Unifocalization with pericardial roll technique in pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries

OBJECTIVE

This study aims to compare both the pericardial roll technique with the patch augmentation technique of the unifocalization, and single-stage complete repair with the unifocalization and shunt for the repair of the ventricular septal defect, pulmonary atresia, and major aortopulmonary collateral arteries.

METHODS

This was a retrospective review of the 48 patients undergoing unifocalization of the ventricular septal defect, pulmonary atresia, and major aorticopulmonary collateral arteries from a single center. Our cohort had two surgical pathways, including single-stage midline unifocalization (n = 40), unifocalization after pulmonary artery rehabilitation by creating an aortopulmonary window or central shunt (n = 8). There were two surgical techniques in single-stage midline unifocalizaton, including widening of the pulmonary arteries with a patch (n = 30), and connecting pulmonary arteries with a pericardial roll (n = 10).

RESULTS

A total of 14 (29.2%) of 48 patients underwent single-stage complete repair, 26 patients underwent shunt palliation with unifocalization. Combined early and late mortality was seen in seven patients in those who underwent shunt palliation with unifocalization, while it was seen in one patient in those who underwent a single-stage complete repair (mortality ratio 26.8% vs. 7.1%, p = .22). There was no statistically significant difference between the pericardial roll and patch augmentation techniques in terms of pulmonary artery reintervention (p = .65). Although all pulmonary artery reinterventions were for unilateral pulmonary artery in the roll technique group, 41.7% of reinterventions were for bilateral pulmonary arteries in the pericardial augmentation group.

CONCLUSION

Single-stage complete repair of the ventricular septal defect, pulmonary atresia, and major aorticopulmonary collateral arteries has better results than unifocalization with a shunt. In terms of nonvaluable raw material, the use of the pericardial roll technique is a considerable alternative for unifocalization.

Relation Between Pulmonary Artery Pressures Measured Intraoperatively and at One-Year Catheterization After Unifocalization and Repair of Tetralogy with Major Aortopulmonary Collateral Arteries

To assess the relationships between pulmonary artery (PA) pressure and the PA:aortic systolic pressure ratio measured intraoperatively and at surveillance catheterization in patients achieving complete unifocalization and repair for tetralogy of Fallot with major aortopulmonary collateral arteries (TOF/MAPCAs). This was a single-center retrospective cohort analysis of all patients who underwent complete repair of TOF/MAPCAs from 2002-2019 and received a postoperative surveillance catheterization at our center 6-24 months after surgery. Associations between intraoperative and catheter hemodynamic data were analyzed. 163 patients were included. Median systolic PA pressure was 30 (quartiles 26, 35) and 35 (28, 42) mmHg intraoperatively and at catherization respectively; systolic aortic pressure 90 (86, 100) and 84 (76, 92); and PA:aortic pressure ratio was 0.33 (0.28, 0.40) and 0.41 (0.34, 0.49). Moderate correlation was found between the intraoperative and catheter-based hemodynamics, with the majority of systolic PA pressures within 10mmHg and PA:Ao systolic ratios within 0.1. Changes in the ratio were influenced to a similar degree by differences in PA and aortic pressures. Surgical and/or catheter reinterventions were more common in patients with both higher intraoperative PA systolic pressure and PA:aortic systolic ratios and in those with greater discrepancy between intraoperative and catheterization values. PA systolic pressure and the PA:aortic systolic pressure ratio measured immediately after repair remain useful metrics for assessing the initial operative PA reconstruction, and as indicators of longer term hemodynamics. Initially elevated and subsequently discrepant PA systolic pressure and PA:aortic systolic pressure ratios were associated with higher rates of reintervention. (Figure 7).

Outcome of patients with tetralogy of Fallot with pulmonary atresia

OBJECTIVE

Tetralogy of Fallot patients with pulmonary atresia (TOFPA) have a largely varying source of pulmonary perfusion with often hypoplastic and even absent central pulmonary arteries. A retrospective single center study was undertaken to assess outcome of these patients regarding type of surgical procedures, long-term mortality, achievement of VSD closure and analysis of postoperative interventions.

METHODS

76 consecutive patients with TOFPA operated between 01.01.2003 and 31.12.2019 are included in this single center study. Patients with ductus dependent pulmonary circulation underwent primary single stage full correction including VSD closure and right ventricular to pulmonary conduit implantation (RVPAC) or transanular patch reconstruction. Children with hypoplastic pulmonary arteries and MAPCAs without double supply were predominantly treated by unifocalization and RVPAC implantation. The follow up period ranges between 0 and 16,5 years.

RESULTS

31 patients (41%) underwent single stage full correction at a median age of 12 days, 15 patients could be treated by a transanular patch. 30 days mortality rate in this group was 6%. In the remaining 45 patients the VSD could not be closed during their first surgery which was performed at a median age of 89 days. A VSD closure was achieved later in 64% of these patients after median 178 days. 30 days mortality rate after the first surgery was 13% in this group. The estimated 10-year-survival rate after the first surgery is 80,5% ± 4,7% showing no significant difference between the groups with and without MAPCAs (p > 0,999). Median intervention-free interval (surgery and transcatheter intervention) after VSD closure was 1,7 ± 0,5 years [95% CI: 0,7-2,8 years].

CONCLUSIONS

A VSD closure could be achieved in 79% of the total cohort. In patients without MAPCAs this was possible at a significant earlier age (p < 0,01). Although patients without MAPCAs predominantly underwent single stage full correction at newborn age, the overall mortality rate and the interval until reintervention after VSD closure did not show significant differences between the two groups with and without MAPCAs. The high rate of proven genetic abnormalities (40%) with non-cardiac malformations did also pay its tribute to impaired life expectancy.

Concomitant Single-Stage Unifocalization and Cavopulmonary Anastomosis (Glenn Shunt) in an Adolescent Patient With Univentricular Physiology and Major Aortopulmonary Collateral Arteries: A Technically Challenging Case

Long-segment pulmonary atresia (PA), non-confluent branch pulmonary arteries, ventricular septal defect, tricuspid valve atresia (type 1A), and single ventricle physiology is a relatively rare and extremely heterogeneous form of congenital heart disease. This subset of patients having pulmonary atresia, ventricular septal defect, and major aortopulmonary collateral arteries (MAPCAs) have to undergo multiple unifocalization staging operations before a complete repair is attempted. Most of the patients were deemed inoperable. We report a rare case of a concomitant single-stage unifocalization and cavopulmonary anastomosis (bi-directional Glenn procedure) in an adolescent cyanotic girl with tricuspid valve atresia (type 1 A), long-segment pulmonary atresia, non-confluent branch pulmonary arteries, bilateral patent ductus arteriosus, MAPCAs, and single-ventricle physiology. Reconstruction of the absent central pulmonary artery and non-confluent branch pulmonary arteries was achieved by dividing the bilateral patent ductus arteriosus feeding the bilateral pulmonary arteries.

Collateral or fistula? Coronary artery as the primary source of pulmonary blood flow in a patient with pulmonary atresia and ventricular septal defect

In patients with pulmonary atresia and ventricular septal defect (PA/VSD), a coronary artery being the primary source of pulmonary blood flow is a rare entity. We describe two cases of PA/VSD with coronary-to-pulmonary artery fistula with emphasis on the role of Computed Tomographic Angiography (CTA) in depicting all the sources of pulmonary blood supply, to predict surgical management and need for unifocalization of Major Aortopulmonary Collateral Arteries (MAPCA's).

Outcomes After Repair of Pulmonary Atresia With Ventricular Septal Defect and Major Aortopulmonary Collateral Arteries: A Tailored Approach in a Developing Setting

Objectives: Pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries (PA/VSD/MAPCAs) is complex and diverse that has led to a variety of treatment strategies. Experience has been largely obtained in the advanced countries. The clinical diversity is greater in China. We evaluated our surgical approaches and outcomes of these patients. Methods: We reviewed 127 patients undergoing varied surgeries in our center in 2010-2019. Results: Thirty patients underwent single-stage complete repair by unifocalizing MAPCAs and VSD closure (aged 3.9-131.4 months, median 22) with 3 (10%) early deaths. Ninety-seven underwent the first-stage rehabilitation strategy including systemic-to-pulmonary shunt in 29 (aged 0.5-144 month, median 8), and palliative RV-PA conduit in 68 (aged 2.2-209.6 months, median 14) with 5 (5.2%) early deaths. Eight-one patients (63.8%) eventually achieved complete repair with a median right/left ventricular (RV/LV) pressure ratio of 0.7 (ranged 0.4-1.0). Fourteen patients (11.0%) accepted palliation as final destination. Survival for the entire cohort was 89.5, 85.2, and 76.1% at 1, 5, and 10 years, respectively. Survival for those undergoing complete repair was 88.2 and 76.6% at 1 and 5 year, respectively. RV/LV pressure ratio ≥0.8 was risk factor for mortality (HR10.3, p = 0.003). Conclusions: Our cohort, the largest from China, had distinctive clinical features with substantially wider age range and higher RV/LV pressure ratio. Using the combined approaches tailored to individual patients, complete repair was achieved in 64% of patients. The early and intermediate outcomes are acceptable compared to many of the previous reports.

Surgical Management of Fallot's Tetralogy With Pulmonary Atresia and Major Aortopulmonary Collateral Arteries: Multistage Versus One-Stage Repair

A strict and rational approach to Fallot's tetralogy with pulmonary atresia and major aortopulmonary collateral arteries allows to achieve optimal results. Rehabilitative and unifocalization strategies do not constitute separate philosophies; instead the surgical strategy should be tailored to each individual patient. Based on our previous experience, the ability to achieve definitive intracardiac repair is the real determinant of both improved survival and adequate systolic right ventricular performance on mid-term follow-up.

Unifocalization and pulmonary artery reconstruction in patients with tetralogy of Fallot and major aortopulmonary collateral arteries who underwent surgery before referral

OBJECTIVE

The study objective was to characterize and analyze outcomes in patients with tetralogy of Fallot and major aortopulmonary collateral arteries who had undergone surgery elsewhere before referral (prereferral surgery).

METHODS

Patients with tetralogy of Fallot and major aortopulmonary collateral arteries who underwent surgery between 2001 and 2019 at our center were reviewed. Prereferral surgery and unoperated patients were compared, as were subsets of prereferral surgery patients who had undergone different types of prior procedures. Primary outcomes included complete repair with survival to 6 months, death, and perioperative metrics.

RESULTS

Of 576 patients studied, 200 (35%) had undergone a wide range and number of prior operations elsewhere, including 92 who had pulmonary blood supply through a shunt and 108 who had a right ventricle pulmonary artery connection. Patients who underwent prereferral surgery with an existing right ventricle pulmonary artery connection had undergone more prereferral surgery procedures than those with a shunt and were more likely to have a right ventricle outflow tract pseudoaneurysm or pulmonary artery stent (all P < .001) at the time of referral. The cumulative incidences of complete repair and death were similar regardless of prereferral surgery status, but the cumulative incidence of complete repair with 6-month survival was higher (P = .002) and of death lower (P = .18) in patients who had prior right ventricle pulmonary artery connection compared with those who had received a prior shunt only.

CONCLUSIONS

Our comprehensive management strategy for tetralogy of Fallot and major aortopulmonary collateral arteries can be applied with excellent procedural results in both unoperated patients and those who have undergone multiple and varied procedures elsewhere.

Comprehensive Management of Major Aortopulmonary Collaterals in the Repair of Tetralogy of Fallot

The heterogenous anatomy of Tetralogy of Fallot with major aortopulmonary collateral arteries has engendered a similar degree of diversity in its management and, ultimately, outcome. We summarize our comprehensive treatment paradigm for this lesion evolved over 15 years of experience through 458 patients and the results obtained. An updated analysis of 307 patients treated primarily at our institution is included. A review of recent literature, comparison of management strategies, and discussion of ongoing controversies are provided.

Approaches to Pulmonary Atresia With Major Aortopulmonary Collateral Arteries

Pulmonary atresia with major aortopulmonary collateral arteries (MAPCAs) is one of the most challenging surgical conditions to manage-not only because of the technical complexity of the surgery but also in terms of defining the anatomy of the pulmonary vasculature, the timing of surgery, and decision making on staged vs complete repair. The importance of early definition of pulmonary blood supply is paramount, establishing which areas of the lung are supplied by MAPCAs alone and which have dual supply with the native system (noting that 20% of patients have absent intrapericardial native vessels). Early unifocalization (3-6 months) is ideal, with closure of the ventricular septal defect (VSD) performed if 15 or more out of 20 lung segments can be recruited. Leaving the ventricular septal defect open with a limiting right ventricle-pulmonary artery conduit can be a useful interim or even definitive circulation in patients with borderline vasculature. Rehabilitation of small native vessels with central shunts can be very effective, but best outcomes are achieved by a combination of unifocalization of MAPCAs together with the native vessels (if present). A variety of reconstructive techniques are necessary to be able to effect these complex repairs with careful choice of materials. Ideally, surgery can be completed through sternotomy alone, but separate thoracotomies may be necessary to control and access some MAPCAs.