[Utilisation of gastric ring systems for pulmonary artery banding: an animal study]

Pulmonary artery banding is often required as a first palliative procedure in infants with congenital heart disease and high pulmonary blood flow or to retrain the left ventricle. The purpose of the study was to demonstrate the safety of a gastric banding system as an adjustable pulmonary artery banding in chronic implantation.

Five ewes underwent implantation of the banding system around the main pulmonary artery through a left thoracotomy. All had functional evaluation with progressive occlusion and opening of the device every two weeks for a total period of three months. Invasive pressure measurements in the right ventricle and aorta were carried out each time.

Devices could be implanted easily. Progressive occlusion and re-opening were possible in all animals during each time point. All animals survived throughout the protocol. Retrieval of the device was achieved in all animals. In one, it was challenging because of the presence of a fibrotic reaction around the device. It died because of pulmonary artery perforation before the sacrifice. At autopsy, microscopic examination showed no signs of myocardial fibrosis.

In animals, gastric banding system is a safe and effective implantable device to adjust pulmonary artery diameter over a prolonged period of time. This new device may be a valuable alternative to the repeated conventional pulmonary artery banding needed for ventricular retraining in humans.