Perforation and right ventricular outflow tract stenting: Alternative palliation for infants with pulmonary atresia/ventricular septal defect

Transcatheter-Based Interventions for Tetralogy of Fallot Across All Age Groups

Tetralogy of Fallot (TOF) is the most common form of cyanotic congenital heart disease. Palliative procedures, either surgical or transcatheter, aim to improve oxygen saturation, affording definitive procedures at a later stage. Transcatheter interventions have been used before and after surgical palliative or definitive repair in children and adults. This review aims to provide an overview of the different catheter-based interventions for TOF across all age groups, with an emphasis on palliative interventions, such as patent arterial duct stenting, right ventricular outflow tract stenting, or balloon pulmonary valvuloplasty in infants and children and transcatheter pulmonary valve replacement in adults with repaired TOF, including the available options for a large, dilated native right ventricular outflow tract.

Accuracy of Fetal Echocardiography in Defining Pulmonary Artery Anatomy and Source of Pulmonary Blood flow in Pulmonary Atresia with Ventricular Septal Defect (PA/VSD)

Precise delineation of central and branch pulmonary artery anatomy, patent ductus arteriosus, and major aorto-pulmonary collateral artery anatomy in the fetal diagnosis of pulmonary atresia with ventricular septal defect is challenging but important to prenatal counseling and postnatal management. We aimed to evaluate the accuracy of fetal echocardiography to determine these anatomical nuances in pulmonary atresia with ventricular septal defect. This was a retrospective, single-institution, 10-year chart review of consecutive prenatal diagnosis of pulmonary atresia with ventricular septal defect for assessment of pulmonary artery, patent ductus arteriosus, and major aorto-pulmonary collateral artery anatomy and comparison with postnatal imaging including echocardiography, cardiac catheterization, and computerized tomography angiography. Twenty-six fetuses were diagnosed with pulmonary atresia with ventricular septal defect during the review period and complete postnatal follow-up was available in 18, all confirming the basic prenatal diagnosis. Fetal echocardiography accurately predicted central and branch pulmonary artery anatomy in 16 (89%) [confluent in 14, discontinuous in 2], patent ductus arteriosus status in 15 (83%) [present in 10, absent in 5], and major aorto-pulmonary collateral arteries in 17 (94%) [present in 9, absent in 8]. Accuracy increased to 100% for pulmonary artery anatomy (16/16) and major aorto-pulmonary collateral artery (17/17) when excluding patients whose anatomy was reported as uncertain on fetal echocardiography. Fetal echocardiography can provide accurate anatomical details in the vast majority of fetuses with pulmonary atresia with ventricular septal defect. This allows for more anatomy-specific counseling, prognostication, and improved selection of postnatally available management options.

Right Ventricular Outflow Tract Stenting as Palliation of Critical Tetralogy of Fallot: Techniques and Results

Background. Despite current trends toward early primary repair, the surgical systemic-to-pulmonary shunt is still considered the first-choice palliation in patients with critical tetralogy of Fallot (TOF) and duct-dependent pulmonary circulation unsuitable for primary repair. However, stenting of the right ventricular outflow tract (RVOT) is nowadays emerging as an effective alternative to surgical palliation in selected patients. Methods and results. RVOT stenting is usually performed from a venous route, either femoral or, in selected cases, the right internal jugular vein. Less frequently, mostly in pulmonary infundibular/valvar atresia, this procedure can be performed using a hybrid surgical/interventional approach by surgical exposure of the RVOT, puncture of the atretic valve, and stent deployment under direct vision. The size and type of the most appropriate stent may be chosen, based on ultrasound measurements of the RVOT, to cover the right ventricular infundibulum completely and, at the same time, sparing the pulmonary valve, unless significant pulmonary valve annulus hypoplasia and/or supra-valvular stenosis is a significant component of the obstruction. In the large series so far published, early mortality of RVOT stenting is less than 2%, comparing favourably with either Blalock-Thomas-Taussig shunt or early primary repair. In addition, morbidity and clinical sequelae of this approach do not significantly differ from surgical palliation, even if RVOT stenting shows lesser durability and a higher rate of trans-catheter re-interventions over a mid-term follow-up. Finally, similar but more balanced pulmonary artery growth than surgical palliation following RVOT stenting is reported over a mid-term follow-up. Conclusions. RVOT stenting is a technically feasible, well-tolerated, and effective palliation in critical TOF. This approach is cost-effective with respect to surgical palliation either in high-risk neonates or whenever a short-term pulmonary blood flow source is anticipated due to the early surgical repair. It effectively increases pulmonary blood flow, improves arterial saturation, and promotes balanced pulmonary artery growth over a mid-term follow-up.

Gudnason J, Synnergren M, Sunnegårdh J. Outcome after surgery for pulmonary atresia with ventricular septal defect, a long-term follow-up study

Aim

To study the long‐term outcome after surgery for pulmonary atresia and ventricular septal defect (PA‐VSD), and to determine association between the contribution of major aorto‐pulmonary collateral arteries (MAPCAs) to the pulmonary blood flow, comorbidity and cause of death.

Methods

Patients who had undergone surgery for PA‐VSD from January 1st 1994 to December 31st 2017 were studied retrospectively. Survival was cross‐checked against the Swedish National Population Register.

Results

Seventy patients were identified, giving an incidence of 5.3 newborns per 100 000 live births. In 41 patients (59%) the pulmonary blood flow originated from a patent ductus arteriosus (PDA), while 29 patients (41%) had contribution of the pulmonary blood flow from MAPCAs. Extracardiac disease was found in 34 patients (49%), 16 of whom had 22q11‐microdeletion syndrome (23%). Survival at follow‐up was similar in patients with and without MAPCAs (72.4% vs. 75.6%, n.s.), with a median follow‐up time of 14.3 years (3.2–41.8 years). No difference was found in mortality in patients with or without any syndrome or extracardiac disease.

Conclusion

Long‐term survival did not differ between those with and without MAPCAs and no difference in mortality was seen in patients with and without concomitant extracardiac disease or any kind of syndrome.

Short to medium term outcomes of right ventricular outflow tract stenting as initial palliation for symptomatic infants with complete atrioventricular septal defect with associated tetralogy of Fallot

OBJECTIVES

To assess the impact of right ventricular outflow tract (RVOT) stenting as the primary palliation in infants with complete atrioventricular septal defect with associated tetralogy of Fallot (cAVSD/TOF).

BACKGROUND

Historically, palliation of symptomatic patients with cAVSD/TOF has been achieved through surgical systemic to pulmonary artery shunting. More recently RVOT stenting has evolved as an acceptable alternative in patients with tetralogy of Fallot.

METHODS

Retrospective review of all patients with cAVSD/TOF who underwent RVOT stenting as palliation over a 13-year period from two large tertiary referral centers.

RESULTS

Twenty-six patients underwent RVOT stenting at a median age of 57 days (interquartile range [IQR] 25.5-106.5). Median weight for stent deployment was 3.7 kg (IQR 2.91-5.5 kg). RVOT stenting improved oxygen saturations from a median of 72% (IQR 70-76%) to 90% (IQR 84-92%), p < .001. There was a significant increase in the median Z-score for both branch pulmonary arteries at median follow-up of 255 days (IQR 60-455). Eight patients required RVOT stent balloon dilatations and 8 patients required re-stenting for progressive desaturation. The median duration between reinterventions was 122 days (IQR 53-294 days). Four patients died during the follow-up period. No deaths resulted from the initial intervention. To date, definitive surgical intervention was achieved in 19 patients (biventricular repair n = 15) at a median age of 369 days (IQR 223-546 days).

CONCLUSION

RVOT stenting in cAVSD/TOF is a safe and effective palliative procedure in symptomatic infants, promoting pulmonary artery growth and improving oxygen saturations.