Pulmonary atresia with ventricular septal defect, extremely hypoplastic pulmonary arteries, major aorto-pulmonary collaterals

Staged correction of pulmonary atresia, ventricular septal defect, and collateral arteries

Objectives

Pulmonary atresia (PA) with ventricular septal defect (VSD) and systemic‐pulmonary collateral arteries (SPCAs) presents with variable anatomy with regard to the pulmonary vasculature, requiring personalized surgical treatment. A protocol consisting of staged unifocalization and correction was employed.

Methods

Since 1989, 39 consecutive patients were included (median age at first operation 13 months). In selected cases, a central aorto‐pulmonary shunt was performed as the first procedure. Unifocalization procedures were performed through a lateral thoracotomy. Correction consisted of shunt takedown, VSD closure, and interposition of an allograft between the right ventricle and the reconstructed pulmonary artery. Echocardiographic data were obtained postoperatively and at interval follow‐up.

Results

In 39 patients 66 unifocalization procedures were performed. Early mortality was 5%. Seven patients were considered not suitable for correction, of which four have since died. One patient is awaiting further correction. A correction was performed successfully in 28 patients. Operative mortality was 3% and late mortality was 11%. Median follow‐up after the correction was 19 years. Eleven patients required homograft replacement. Freedom from conduit replacement was 88%, 73%, and 60% at 5, 10, and 15 years respectively. Right ventricular function was reasonable or good in 75% of patients. All but one patient were in NYHA Class I or II.

Conclusions

After complete unifocalization 30/37 patients (81%) were considered correctable. The staged approach of PA, VSD, and SPCAs results in adequate correction and good functional capacity. RV function after correction remains reasonable or good in the majority of patients.

Pulmonary atresia with ventricular septal defect and tetralogy of Fallot: transannular path augmentation versus systemic to pulmonary artery shunt for first-stage palliation

BACKGROUND

Pulmonary atresia with ventricular septal defect and severe tetralogy of Fallot require a palliative procedure for pulmonary artery rehabilitation. For first-stage palliation, two main surgical options are still debated: right ventricle to pulmonary artery connection and modified Blalock-Taussig shunt. We compared the clinical outcomes of the two procedures.

METHODS

From 1995 to 2018, 88 patients needed palliation (pulmonary atresia with ventricular septal defect n = 47; tetralogy of Fallot n = 41). Among these patients, 70 modified Blalock-Taussig shunt and 18 transannular path augmentation were performed before 6 months of age. Using a 1:1 propensity score match analysis, 20 patients were included in the analysis. The primary outcome was in-hospital mortality and pulmonary artery growth.

RESULTS

After matching, the pre-operative Nakata was smaller in transannular path augmentation 54 ± 24 mm2/m2 than modified Blalock-Taussig shunt 109 ± 31 mm2/m2 (p < 0.001). The age and weight were similar (p = 0.31 and p = 0.9, respectively). There was no difference in in-hospital mortality (p = 0.3). The Nakata index before biventricular repair and delta Nakata were smaller in modified Blalock-Taussig shunt group (206 ± 80 mm2/m2, 75 ± 103 mm2/m2) than transannular path augmentation (365 ± 170 mm2/m2, 214 ± 165 mm2/m2; p = 0.03; p < 0.001). Median time to biventricular repair was similar (p = 0.46). The rate of interstage reintervention was similar (p = 0.63).

CONCLUSIONS

The transannular path augmentation is better for the rehabilitation of the native pulmonary artery. Despite a smaller pulmonary artery, right ventricle to pulmonary artery connection is equivalent to modified Blalock-Taussig shunt for rate of biventricular repair and time to biventricular repair.

Outcomes of palliative right ventricle to pulmonary artery connection for pulmonary atresia with ventricular septal defect

OBJECTIVES

To determine the early, intermediate and long-term outcomes of pulmonary atresia with ventricular septal defect (PA/VSD) Types I, II and III initially palliated by a right ventricle to pulmonary artery (RVPA) connection.

METHODS

We performed a retrospective study from 2000 to 2014 that included 109 patients with PA/VSD who had undergone an RVPA connection (tetralogy of Fallot and PA/VSD Type IV excluded). The end-points of this strategy were adequate pulmonary artery tree post-palliation, second palliation, biventricular repair, right ventricular pressure post-biventricular repair and late reoperation. Mean follow-up was 5.4 years (1 day to 14-78 years).

RESULTS

Early mortality after an RVPA connection was 2.7% (3 of 109). The interstage mortality rate was 6.6% (7 of 106). Eighty-four (77%) patients had a biventricular repair and 8 patients (7%) are awaiting repair. Overall survival was 90% at 1 year and 81% at 10 years. The RVPA connection allowed significant growth of the native pulmonary artery with a Nakata index of 101 mm2/m2 before the RVPA connection and 274 mm2/m2 after (P = 0.001). Twenty-nine reinterventions for restrictive pulmonary blood flow have been done (9 before 2 months and 20 after 2 months). Of the 84 patients who had a repair, 22 patients (26%) initially had a right ventricular pressure greater than 40 mmHg. Twenty-eight patients (33%) required late reoperation.

CONCLUSIONS

Hospital deaths after the RVPA connection were low. The procedure allowed good growth of the native pulmonary artery. Biventricular repair was possible in a large number of cases. The late morbidity rate remains significant. Early reinterventions could be avoided by appropriate calibration. This technique appears to be suitable for any type of PA/VSD with central pulmonary arteries.

Bleeding in the lung complicates a routine intracardiac repair: What went wrong!!!

Cyanotic congenital heart disease presents an increased tendency to bleed in view of subtle coagulation defects. Airway bleeding can be particularly difficult to manage while maintaining an adequate ventilation. An isolated lung bleed with the exclusion of possible traumatic, medical and surgical causes of bleeding, should alert the attending anesthesiologist to the possibility of the collateral-related bleeding. Preoperative coil embolization remains an important initial management step in a case of tetralogy of Fallot (TOF) with major aortopulmonary collaterals. Nevertheless, the coiling of the collaterals in certain specific case scenarios is not feasible, rendering the management of a lung bleed, all the more challenging. We, hereby discuss a case of a 7-year-old girl with a massive endotracheal bleed at the time of weaning from cardiopulmonary bypass after corrective surgery for TOF. The subsequent approach and management are discussed. The optimal management of tetralogy with collaterals mandates an effective communication among the cardiologist, radiologist, anesthesiologist, and the surgeon.

Catheter, MRI and CT Imaging in Newborns with Pulmonary Atresia with Ventricular Septal Defect and Aortopulmonary Collaterals: Quantifying the Risks of Radiation Dose and Anaesthetic Time

A comprehensive understanding of the native pulmonary blood supply is crucial in newborns with pulmonary atresia with ventricular septal defect and aortopulmonary collaterals (PA/VSD/MAPCA). We sought to describe the accuracy in terms of identifying native pulmonary arteries, radiation dose and anaesthetic time associated with multi-modality imaging in these patients, prior to their first therapeutic intervention. Furthermore, we wanted to evaluate the cumulative radiations dose and anaesthetic time over the study period. Patients with PA/VSD/MAPCA diagnosed at < 100 days between 2004 and 2014 were identified. Cumulative radiation dose and anaesthetic times were calculated, with imaging results compared with intraoperative findings. We then calculated the cumulative risks to date for all surviving children. Of 19 eligible patients, 2 had echocardiography only prior to first intervention. The remaining 17 patients underwent 13 MRIs, 4 CT scans and 13 cardiac catheterization procedures. The mean radiation dose was 169 mGy cm² (47-461 mGy cm²), and mean anaesthetic time was 111 min (33-185 min). 3 children had MRI only with no radiation exposure, and one child had CT only with no anaesthetic. Early cross-sectional imaging allowed for delayed catheterisation, but without significantly reducing radiation burden or anaesthetic time. The maximum cumulative radiation dose was 8022 mGy cm² in a 6-year-old patient and 1263 min of anaesthetic at 5 years. There is the potential to generate very high radiation doses and anaesthetic times from diagnostic imaging alone in these patients. As survival continues to improve in many congenital heart defects, the important risks of serial diagnostic imaging must be considered when planning long-term management.

Promoting Pulmonary Arterial Growth via Right Ventricle-to-Pulmonary Artery Connection in Children With Pulmonary Atresia, Ventricular Septal Defect, and Hypoplastic Pulmonary Arteries

Background:

Complete repair of pulmonary atresia (PA) ventricular septal defect (VSD) with hypoplastic or absent native pulmonary arteries, often with major aortopulmonary collateral arteries (MAPCAs), involves construction of an adequate sized pulmonary arterial tree. We report our results with a previously described staged strategy using initial right ventricle (RV)-to-reconstructed pulmonary arterial tree (RV-PA) connection to promote pulmonary arterial growth and facilitate later ventricular septation.

Methods:

We retrospectively reviewed data for all patients (N = 10) with initial echocardiographic diagnosis of PA-VSD and hypoplastic pulmonary arteries operated in our center from October 2008 to August 2016. Pulmonary arterial vessel size measured on preoperative and postoperative angiography was used to calculate Nakata index.

Results:

Seven patients had PA-VSD, three had virtual PA-VSD, and seven had MAPCAs. All underwent creation of RV-PA connection at a median age of 7.5 days and weight 3.6 kg. Eight patients had RV-PA conduits, two had a transannular patches, and seven had major pulmonary artery reconstruction simultaneously. There were no deaths or serious morbidity; one conduit required revision prior to complete repair. Complete repair with ventricular septation and RV pressure less than half systemic was achieved in all patients at a median age of 239 days. Nakata index in neonatal period was 54 mm2/m2 (range 15-144 mm2/m2) and at time of septation 184 mm2/m2 (range 56-510 mm2/m2; P = .004). Growth rates of right and left branch pulmonary arteries were similar. The 10 patients underwent 28 catheterizations with 13 interventions in 8 patients prior to full repair.

Conclusion:

Early palliative RV-PA connection promotes pulmonary arterial growth and facilitates eventual full repair with VSD closure with low RV pressure and operative risk.

Outcomes of the rehabilitative procedure for patients with pulmonary atresia, ventricular septal defect and hypoplastic pulmonary arteries beyond the infant period

OBJECTIVES

To determine the effect and safeness of the right ventricle to pulmonary artery connection with occlusion of major aortopulmonary collaterals and pulmonary artery angioplasty to rehabilitate the hypoplastic pulmonary arteries in patients with pulmonary atresia and ventricular septal defect beyond the infant period.

METHODS

From December 2009 to August 2012, 37 consecutive patients (mean age 1.9 ± 1.7 years, range 0.6-7.2 years) diagnosed with pulmonary atresia, ventricular septal defect and pulmonary artery hypoplasia (Nakata index 90.9 ± 42.6 mm(2)/m(2); McGoon ratio 1.0 ± 0.2) were included in this retrospective study. All patients underwent the procedure of right ventricle to pulmonary artery connection, during which most of them received transcatheter occlusion of major aortopulmonary collaterals and/or pulmonary angioplasty. Mean follow-up was 1.6 ± 0.8 years (range 0.6-3.3 years). Continuous variables are expressed as means ± standard deviation.

RESULTS

There were no early deaths, but one patient died of myocarditis 1 year after the rehabilitation. Significant pulmonary artery growth was obtained (Nakata index 215.1 ± 95.1 mm(2)/m(2), P < 0.001; McGoon ratio 1.6 ± 0.5, P < 0.001) in all of the 37 patients, and among them, 17 patients (45.9%) whose pulmonary growth was considered adequate obtained a complete repair without perforation of the ventricular septal defect. The preoperative McGoon ratio might be a good predictor for adequate pulmonary growth. There was one early death after anatomical repair. At the last visit, all survivors who underwent anatomical repair were in New York Heart Association class I-II with satisfactory haemodynamics.

CONCLUSIONS

Connection of the right ventricle to the pulmonary artery is safe and effective to promote the growth of the native pulmonary arteries in patients with pulmonary atresia, ventricular septal defect and hypoplastic native pulmonary arteries. Ultimately, this strategy allows complete repair in the majority of patients beyond infancy.

Growth of diminutive central pulmonary arteries after right ventricle to pulmonary artery homograft implantation

BACKGROUND

The management of tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collateral arteries is controversial because of the wide variability of pulmonary artery (PA) and major aortopulmonary collateral arteries morphology. Several different staged strategies have been used to promote growth of diminutive PA branches. We have preferred a right ventricular (RV)-PA homograft for symmetrical growth of the central PA branches. In this study we evaluated the success of this strategy.

METHODS

Between 2006 and 2012, 23 patients with pulmonary atresia and diminutive PAs underwent RV-PA homograft implantation. Median age was 2 months (range, 4 days to 18 months), and median body weight was 5.1 kg (range, 1.7 to 8.5 kg). The type of homograft was aortic in 8, pulmonary in 6, and femoral vein in 9. The mean diameter of the homograft was 10.5 mm (range, 6 to 16 mm). All procedures were performed on cardiopulmonary bypass. The PA diameter was measured at the time of the operation and subsequent catheterization.

RESULTS

The median size of the branch PA was 2.1 mm. In the 18 patients who had serial assessment of PA size, the right PA increased by 307% ± 184%, the left PA increased by 283% ± 139%, and the Nakata index increased from 28.8 ± 20.1 mm(2)/m(2) to 253 ± 96 mm(2)/m(2) during a median period of 347 days (range, 44 to 1,520 days). The PA growth ratio (PA growth in mm/mo) was similar between the right PA (0.42 ± 0.46 mm/mo) and the left PA (0.43 ± 0.47 mm/mo). There was no acute conduit failure. Seventeen patients required 28 percutaneous interventions for embolization of an aortopulmonary collateral or stenosis of the conduit or PA. There were no hospital deaths. Three patients died late after other procedures during a mean follow-up of 44.7 months. Twenty patients (87%) have undergone complete repair to date.

CONCLUSIONS

RV-PA homograft implantation can be performed in neonates and infants with minimal risk of acute occlusion. The RV-PA homograft promotes rapid and balanced growth of central pulmonary arteries leading to complete repair in most patients.

Neonatal right ventricle to pulmonary connection as a palliative procedure for pulmonary atresia with ventricular septal defect or severe tetralogy of Fallot

OBJECTIVES

Right ventricle to pulmonary artery connection (RVPA connection) without prosthetic material has been our ideal strategy to palliate pulmonary atresia with ventricular septal defect (VSD) or severe tetralogy of Fallot for the last decade. We speculate that RVPA connection ensures adequate postoperative haemodynamics for symptomatic neonates and promotes pulmonary artery rehabilitation. The present study was undertaken to assess the outcome of this strategy.

METHODS

Between 2000 and 2010, among 107 patients who benefited from an RVPA connection, 57 were neonates. Forty-eight of these underwent autologous tissue reconstruction, 5 using left atrial appendage. Median weight was 2.9 kg (range 1.8-4.4). Median Nakata index was 100 mm2/m2 (range 17-185 mm2/m2); 12% had major aortopulmonary collaterals. All patients were reviewed retrospectively. End-points were death or complete repair; reintervention for restrictive pulmonary blood flow was considered as failure. At follow-up, we evaluated reintervention after complete repair, and quality of life.

RESULTS

There were 2 early deaths (RV hypoplasia and RV failure) and 3 late sudden deaths (range 3-6 months). Pulmonary blood flow required to be increased in 8 patients: 4 underwent shunt after a median delay of 1 month; RVPA connection enlargement was needed in 3; 1 patient had percutaneous angioplasty. Finally, 47 patients (81%) had a complete repair, of which 70% were performed without prosthetic material at a median age of 7 months (range 2-53), with a median Nakata index of 221 mm2/m2 (range 102-891). One patient died early and 1 was a failure with opening of the VSD after intracardiac repair. At last follow-up, 4 patients were still awaiting repair, with 1 late death and 5 who had required reintervention after intracardiac repair; there were 3 conduit replacements and 2 balloon dilatation patch enlargements.

CONCLUSIONS

The neonatal RVPA connection approach (i) provides an acceptable survival rate with a satisfactory haemodynamic adaptation, (ii) facilitates rehabilitation of PAs and (iii) avoids the use of prosthetic graft at correction.

Management of patients with pulmonary atresia, ventricular septal defect, hypoplastic pulmonary arteries and major aorto-pulmonary collaterals: Focus on the strategy of rehabilitation of the native pulmonary arteries

Pulmonary atresia with ventricular septal defect (VSD), hypoplastic native pulmonary arteries (PAs) and major aorto-pulmonary collateral arteries (MAPCAs) is a rare and complex congenital cardiac disease. In broad outline, two surgical approaches are available for patients with this condition. The first is characterized by one or several stages of complete unifocalization of the supplying MAPCAs, with or without incorporation of the native pulmonary arteries (PAs), connection of the right ventricle to the 'neo-Pas' and, if possible, concomitant or delayed closure of the VSD. The second strategy is based on rehabilitation of the native pulmonary arteries. The first step is a direct right ventricle to native PA connection, to promote the growth of native PAs. The establishment of antegrade flow also allows an easier approach for interventional catheterization, enabling dilatation or stenting of the stenosis and then closure of the communicant collaterals. When the development of the native PAs is satisfactory, the complete repair is performed. If it is necessary to suture a MAPCA to the PA ('unifocalization'), this is accomplished by connecting the collateral artery to an already developed native branch. Our team developed this multidisciplinary strategy with good results. Based on this experience as well as on the published literature, we describe this strategy of management of patients with pulmonary atresia, VSD, hypoplastic pulmonary arteries and major aorto-pulmonary collaterals (MAPCAs).

Outcome of Staged Repair of Tetralogy of Fallot with Pulmonary Atresia and a Ductus-dependent Pulmonary Circulation: Should Primary Repair Be Considered?

BACKGROUND

The tetralogy of Fallot (TOF) with pulmonary atresia (PA) and a ductus-dependent pulmonary circulation (no major aorto-pulmonary collateral arteries (MAPCAs)) has been treated with staged repair or primary repair depending on the preference of surgeons or institutions. We evaluated the 19-year outcome of staged repair for this anomaly to find out whether our surgical strategy should be changed.

MATERIALS AND METHODS

Forty-four patients with TOF/PA with patent ductus arteriosus (PDA) who underwent staged repair from June 1991 to October 2010 were included in this retrospective study. The patients with MAPCAs were excluded. The average age at the first palliative shunt surgery was 40.8±67.5 days (range: 0~332 days). Thirty-one patients (31/44, 70%) were neonates. The average weight was 3.5±1.6 kg (range: 1.6~8.7 kg). A modified Blalock-Taussig (BT) shunt was performed in 38 patients, classic BT shunt in 4 patients, and central shunt in 2 patients. Six patients required concomitant procedures: pulmonary artery angioplasty was performed in 4 patients, pulmonary artery reconstruction in one patient, and re-implantation of the left pulmonary artery to the main pulmonary artery in one patient. Four patients required a second shunt operation before the definitive repair was performed. Thirty-three patients underwent definitive repair at 24.2±13.3 months (range: 7.3~68 months) after the first palliative operation. The average age at the time of definitive repair was 25.4±13.5 months (range: 7.6~68.6 months) and their average weight was 11.0±2.1 kg. For definitive repair, 3 types of right ventricular outflow procedures were used: extra-cardiac conduit was performed in 30 patients, trans-annular patch in 2 patients, and REV operation in 1 patient. One patient was lost to follow-up after hospital discharge. The mean follow-up duration for the rest of the patients was 72±37 months (range: 4~160 months).

RESULTS

Ten patients (10/44, 22.7%) died before the definitive repair was performed. Four of them died during hospitalization after the shunt operation. Six deaths were thought to be shunt-related. The average time of shunt-related deaths after shunt procedures was 8.7 months (range: 2 days~25.3 months). There was no operative mortality after the definitive repair, but one patient died from dilated cardiomyopathy caused by myocarditis 8 years and 3 months after the definitive repair. Five-year and 10-year survival rates after the first palliative operation were 76.8% and 69.1%, respectively.

CONCLUSION

There was a high overall mortality rate in staged repair for the patients with TOF/PA with PDA. Majority of deaths occurred before the definitive repair was performed. Therefore, primary repair or early second stage definitive repair should be considered to enhance the survival rate for patients with TOF/PA with PDA.

Unifocalization of major aortopulmonary collateral arteries in pulmonary atresia with ventricular septal defect is essential to achieve excellent outcomes irrespective of native pulmonary artery morphology

OBJECTIVE

Pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries is a complex lesion with a high rate of natural attrition. We evaluated the outcomes of our strategy of unifocalization in the management of these patients.

METHODS

From 1989 to 2008, 216 patients entered a pathway aiming for complete repair by unifocalizing major aortopulmonary arteries to a right ventricle-pulmonary artery conduit with ventricular septal defect closure. Where ventricular septation was not possible, definitive repair was considered to include pulmonary artery reconstruction and a right ventricle-pulmonary artery conduit or systemic shunt. Native pulmonary artery morphology was classified into confluent intrapericardial (n = 139), confluent intrapulmonary (n = 51), and nonconfluent intrapulmonary (n = 26).

RESULTS

A total of 203 patients (85%) had definitive repair at a median age of 2.0 years. There was no statistically significant difference in survival after complete repair among the 3 morphologic pulmonary artery groups (P = .18). A total of 132 patients (56%) had complete repair with ventricular septal defect closure, as a single procedure in 111 patients and a staged procedure in 21 patients. Focalization of major aortopulmonary collateral arteries with proven long-term patency with the right ventricle was associated with a survival benefit compared with 14 patients in whom unifocalization was not possible and who had only systemic shunts. Overall survival was 89% at 3 years after definitive repair. During follow-up, 190 patients required 196 catheter reinterventions and 60 surgical reinterventions.

CONCLUSION

By using a strategy of unifocalization, intrapericardial pulmonary artery reconstruction, and right ventricle-pulmonary artery conduit, excellent long-term survival can be achieved in this group of patients even in the absence of native intrapericardial pulmonary arteries.

Individualized approach to the surgical treatment of tetralogy of Fallot with pulmonary atresia

BACKGROUND

Tetralogy of Fallot with pulmonary atresia is a heterogeneous group of defects, characterised by diverse sources of flow of blood to the lungs, which often include multiple systemic-to-pulmonary collateral arteries. Controversy surrounds the optimal method to achieve a biventricular repair with the fewest operations while basing flow to the lungs on the native intrapericardial pulmonary arterial circulation whenever possible. We describe an individualized approach to this group of patients that optimizes these variables.

METHODS

Over a consecutive 10-year period, we treated 66 patients presenting with tetralogy of Fallot and pulmonary atresia according to the source of the pulmonary arterial flow. Patients were grouped according to whether the flow of blood to the lungs was derived exclusively from the intrapericardial pulmonary arteries, as seen in 29 patients, exclusively from systemic-to-pulmonary collateral arteries, as in 5 patients, or from both the intrapericardial pulmonary and collateral arteries, as in the remaining 32 patients. We divided the latter group into 9 patients deemed simple, and 23 considered complex, according to whether the pulmonary arterial index was greater than or less than 90 millimetres squared per metre squared, and whether the number of collateral arteries was less than or greater than 2, respectively.

RESULTS

We achieved complete biventricular repair in 58 patients (88%), with an overall mortality of 3%. Repair was accomplished in a single stage in all patients without systemic-to-pulmonary collateral arteries, but was staged, with unifocalization, in the patients lacking intrapericardial pulmonary arteries. Complete repair without unifocalization was achieved in all patients with the simple variant of the mixed morphology, and in 56% of patients with the complex variant. The average number of procedures per patient to achieve complete repair was 1, 2.2, 3.8, and 2.6 in patients with exclusively native intrapericardial, simple and mixed, complex and mixed and exclusively collateral pulmonary arterial flow, respectively.

CONCLUSIONS

An individualized approach based on the morphology of the pulmonary arterial supply permits achievement of a high rate of complete intracardiac repairs, basing pulmonary arterial flow on the intrapericardial pulmonary arteries in the great majority of cases, and has a low rate of reoperation and mortality.

Surgical management of pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals: a protocol-based approach

Historically, outcomes of pulmonary atresia with ventricular septal defect and major aortopulmonary collaterals have been quite poor. Over the past 15 years, our group has strived to apply a consistent surgical strategy for this lesion based on two guiding principles: early unifocalization of all important collaterals; and the early establishment of a low-pressure pulmonary arterial bed, preferably using simultaneous intracardiac repair. We describe a management protocol that has been developed to handle the highly variable nature of pulmonary blood flow observed with this lesion.

Magnetic guide-wire navigation in pulmonary and systemic arterial catheterization: initial experience in pigs

PURPOSE

Cardiovascular catheterization can be challenging whenever a stenosis or an abnormal vascular course interferes with probing the target vessel. This study addresses the feasibility of navigating a guide wire with a magnetic tip by an external magnetic field through pulmonary and systemic arteries in an experimental porcine model.

MATERIALS AND METHODS

We investigated six piglets using magnetic guide-wire navigation. Two pulmonary arteriograms were taken from different angles in order to reconstruct the three-dimensional vessel anatomy. A computer interface then calculated three-dimensional coordinates for the vessel in space. Using these coordinates, two external magnets were positioned to create magnetic vectors along the expected vessel course. Magnetically enabled guide wires were then navigated into the vessels using the magnetic field to orient the guide-wire tips. Aortic and renal branches were addressed in a similar fashion. Difficulty in reaching the target vessel was reflected by the number of attempts that were necessary. After 10 failed attempts, the maneuver was recorded to have failed.

RESULTS

Thirty-five of 37 (94.6%) arteries with branches at acute angles were reached successfully using magnetic navigation. In two pigs, the left upper lobe artery could not be probed. Peripheral arteries of small diameter were easier to reach than large central arteries, requiring less attempts.

CONCLUSIONS

Magnetic guide-wire navigation is feasible in the arteries of the lungs, the head and neck, and the kidneys. It is particularly useful in entering small arterial branches at acute angles and may facilitate interventional therapy in a variety of vascular diseases in children and adults.

Independent factors associated with mortality, reintervention, and achievement of complete repair in children with pulmonary atresia with ventricular septal defect

OBJECTIVES

We described morphologic characteristics, particularly pulmonary anatomy, and determined the prevalence of definitive end states and their determinants in children with pulmonary atresia associated with ventricular septal defect (PAVSD).

BACKGROUND

Pulmonary atresia associated with ventricular septal defect represents a broad morphologic spectrum that greatly influences management and outcomes.

METHODS

From 1975 to 2004, 220 children with PAVSD presented to our institution. Blinded angiographic review (n = 171) characterized bronchopulmonary segment arterial supply.

RESULTS

A total of 185 patients underwent surgery, and repair was definitive in 75%. Initial operations included systemic-pulmonary artery shunt in 57%, complete primary repair in 31%, or right ventricular outflow tract reconstruction in 12%. Based on angiographic review, 118 patients had simple PAVSD and 53 patients had PAVSD with major aortopulmonary collateral arteries (MAPCAs). Overall survival from initial operation was 71% at 10 years. Risk factors for death after initial operation included younger age at repair, earlier birth cohort, fewer bronchopulmonary segments supplied by native pulmonary arteries, and initial placement of a systemic-pulmonary artery shunt. Competing-risks analysis for initially palliated patients predicted that after 10 years, 68% achieved complete repair (with associated factors including later birth cohort and more bronchopulmonary segments supplied by native pulmonary arteries), 22% died without repair, and 10% remained alive without repair. Reoperations after complete repair occurred in 38 children (27%), with risk factors including older age at palliation, MAPCAs, and more segments supplied by collaterals.

CONCLUSIONS

Outcomes in children with PAVSD have improved over time, and are better in completely repaired cases. Bronchopulmonary arterial supply is an important determinant of mortality, achievement of definitive repair, and post-repair reoperation.

The influence of pulmonary artery morphology on the results of operations for major aortopulmonary collateral arteries and complex congenital heart defects

OBJECTIVE

Congenital heart defects with major aortopulmonary collateral arteries show marked variability in the size and distribution of native pulmonary arteries. We sought to classify the size and distribution of native pulmonary arteries and to determine their influence on surgical outcome.

METHODS

Between 1989 and 2002, 164 patients underwent surgical intervention for congenital heart defects with major aortopulmonary collateral arteries (median age, 10 months). Three patterns of native pulmonary arteries were identified: intrapericardial native pulmonary arteries present (group I); confluent intrapulmonary native pulmonary arteries without intrapericardial native pulmonary arteries (group II); and nonconfluent intrapulmonary native pulmonary arteries (group III). Thirty-seven (23%) patients had single-stage and 76 (47%) patients had multistage complete repair. Thirty (18%) patients await septation, and 8 (5.0%) patients are not septatable. Follow-up is 98% complete (median follow-up, 5.8 years).

RESULTS

In the 164 patients there were 15 (9.1%) early and 12 (7.3%) late deaths. Early mortality after complete repair was 4.4% (n = 5). Actuarial survival was 90% +/- 3% and 85% +/- 4% at 1 and 10 years, respectively. Actuarial freedom from surgical or catheter reintervention in septated patients was 77% +/- 4% and 45% +/- 8% at 1 and 10 years, respectively. On multivariate analysis, the morphology of the native pulmonary arteries was the only factor that influenced actuarial survival after complete repair (P =.04). Group III had the highest risk of death after septation (P =.008). Group II fared better than group III after the initial operation (P <.05).

CONCLUSIONS

Current classifications of congenital heart defects with major aortopulmonary collateral arteries are based on the presence or absence of intrapericardial pulmonary arteries. We have identified a subgroup without intrapericardial native pulmonary arteries but with confluent intrapulmonary native pulmonary arteries. This group has a better outcome than those with nonconfluent intrapulmonary native pulmonary arteries.

Techniques and applications of transcatheter embolization procedures in pediatric cardiology

Transcatheter embolization of congenital or acquired superfluous vascular structure has become routine procedures performed by interventional pediatric cardiologists. Embolization procedure is often part of a collaborative effort with cardiac surgeons to palliate complex congenital heart defect, such as in embolizing aortopulmonary collateral arteries in patient with single ventricle physiology. In other cases, the procedure is the definitive treatment as in embolizing coronary artery fistula. Pediatric cardiologists performing embolization procedures should be familiar with available technologies as well as understand the underlying cardiac anatomy and pathophysiology. This article provides a comprehensive review of presently available embolization agents and technologies. Some of the technologies are used only by interventional radiologists but may be useful to pediatric cardiologists. Specific clinical applications in pediatric cardiology are also discussed with summary of current literature. With continue advancement in transcatheter technology and operator expertise, all unwanted vascular communication should be amenable to transcatheter embolization.

Staged repair of pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries: Experience with 104 patients

OBJECTIVE

To determine the early and intermediate-term outcome of the staged repair used to treat children with pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries.

METHODS

We reviewed a retrospective case series of 104 patients with this complex lesion. Information was obtained from medical records and referring physicians.

RESULTS

Of the 104 patients treated with the staged repair, 58 achieved completion of anatomic repair. The 10-year mortality was 16.5%. In the patients with complete repair, the median right-to-left ventricle pressure ratio was 0.5. The overall surgical reoperation rate was 17%, and 15.5% of patients required postoperative interventional cardiac catheterization. In the multivariate analysis, the number of collateral vessels incorporated in the repair was found to be an independent risk factor for postoperative mortality and an elevated right-to-left ventricle pressure ratio after complete repair.

CONCLUSION

The staged repair can be successfully used to treat patients with pulmonary atresia with ventricular septal defect and major aortopulmonary collateral arteries. This method yields a relatively low mortality with good functional results.

Staged repair of tetralogy of Fallot with pulmonary atresia and major aortopulmonary collateral arteries

OBJECTIVE

To assess the results of a staged surgical approach for tetralogy of Fallot with pulmonary atresia, hypoplastic or absent pulmonary arteries, and major aortopulmonary collateral arteries.

METHODS

We retrospectively reviewed a consecutive series of these patients from a single institution.

RESULTS

From July 1993 to April 2001, 46 consecutive patients with tetralogy of Fallot, pulmonary atresia, and major aortopulmonary collateral arteries were treated with staged surgical repair. The operative sequence usually began with a central aortopulmonary shunt followed by unifocalization of aortopulmonary collateral arteries depending on the source and distribution of pulmonary blood flow. Twenty-eight patients (61%) subsequently underwent complete repair with ventricular septal defect closure and right ventricle to pulmonary artery connection. Those patients who underwent complete repair had a median of 3 total operations (range 1-6). The ratio of the mean pulmonary artery pressure to the mean systemic blood pressure at the time of complete repair was 0.36 (range 0.19-0.58). Two of the 28 repaired patients (7.1%) required subsequent fenestration of the ventricular septal defect closure due to later development of supersystemic right ventricular pressure and right ventricular failure. Eighteen patients (39%) have undergone 1 or more staging operations and are considered good candidates for eventual complete repair. There were no hospital deaths. There was 1 late death (2.2%; 95% CI 0.4-11.3%) in a patient born prematurely who developed severe bronchopulmonary dysplasia precluding complete repair.

CONCLUSIONS

For tetralogy of Fallot with pulmonary atresia and major aortopulmonary collateral arteries, a staged surgical approach yields low overall mortality and acceptable hemodynamics after complete repair.