Waterston anastomosis for initial palliation of tetralogy of Fallot

Transcatheter creation of an aortopulmonary shunt in an animal model

BACKGROUND

The surgical creation of an aortopulmonary shunt is an important tool in the therapy of complex congenital heart defects. We report on a transcatheter approach to establish an aortopulmonary shunt in piglets.

MATERIAL, METHODS AND RESULTS

In 10 piglets with a median body weight of 10.5 kg (8-12 kg), a central aortopulmonary shunt was created by radiofrequency perforation from the aorta to the pulmonary trunk, followed by stent implantation. The procedures were performed via the femoral vessels through 5F sheaths under biplane fluoroscopy guidance. A total of six bare metal coronary stents and five polytetrafluoroethylene-covered coronary stents of 3-4 mm diameter were deployed. Four animals were sacrificed immediately after intervention; six pigs were reevaluated 4-5 weeks later for stent patency and measurement of shunt volume. The procedure was successful in all pigs. Median shunt volume was Qp:Qs = 2.4:1. At re-evaluation median body weight had increased to 18 kg (15.5-27.5 kg) P < 0.028. Four of six stents were completely obstructed due to tissue ingrowth in the bare metal stents (two cases) and thrombus formation in the covered stents (two cases). A third bare metal stent had a residual lumen, and a third covered stent was fully open without any thrombus formation or tissue ingrowth.

CONCLUSIONS

Transcatheter creation of an aortopulmonary shunt by radiofrequency perforation and stent implantation is feasible. The use of appropriate covered stents and an effective anticoagulatory regimen seem to be crucial to keep the shunts open.

Growth of the pulmonary artery after neonatal balloon dilatation of the right ventricular outflow tract in an infant with the tetralogy of Fallot and atrioventricular septal defect

A two week old girl with tetralogy of Fallot and atrioventricular septal defect underwent palliation, for severe hypoxaemia, by balloon dilatation to the right ventricular outflow tract. This procedure was repeated once over the next eight months without complications. Serial right ventricular angiograms showed growth of the hypoplastic pulmonary ring ("annulus"), trunk, and arteries. Balloon dilatation is an alternative palliative procedure for patients with the tetralogy of Fallot which may promote growth of the pulmonary ring, trunk, and arteries.

Balloon dilatation of the pulmonary valve in the first year of life in patients with tetralogy of Fallot: a preliminary study

Fifteen infants with tetralogy of Fallot, who would otherwise have required a palliative operation, underwent balloon dilatation of the right ventricular outflow tract. The mean period of palliation was 8.5 months (range 0-26 months). The procedure was performed without serious complications on 88% of occasions. This preliminary study suggests that balloon dilatation may be useful in the management of tetralogy of Fallot.

The surgical treatment of tetralogy of Fallot

This is a review of the last 307 patients with tetralogy of Fallot who were operated on in our unit at Groote Schuur Hospital and Red Cross War Memorial Children's Hospital. Complete repair was undertaken in 301 patients, and shunts were performed in 6 children. There were 17 hospital deaths and 1 late death. The mortality was 5.5% for children less than 12 years old and 6.6% in patients between 12 and 20 years old. During this study period, there was a change in our policy as to when complete repair should be attempted. At present, we perform systemic-pulmonary shunts in patients less than 6 months old and delay complete repair until the child is 2 years old. In deciding whether a shunt should precede complete repair, our experience has shown that age is not as important a consideration as the anatomy of the outflow tract of the right ventricle and pulmonary arteries.