Balloon dilatation of pulmonary artery banding in dogs: an experimental study.

The technique at our institution for banding of the pulmonary artery (PA) makes debanding by balloon dilatation theoretically possible. Previously we tested this hypothesis in an in vitro study (see previous article in this issue). This study describes balloon dilatation in dogs. Eight Labrador Retriever dogs had a PA band placed early in life, and when their body weight had doubled, they were restudied and debanded by balloon dilatation or surgical removal. One dog died of a virus infection before debanding and was excluded from the study. Five of the dogs (groups 1 and 2) underwent balloon dilatation with satisfactory relief of the gradient across the PA band. Two dogs (group 3) underwent surgical debanding without a plastic procedure on the PA, and this also produced satisfactory relief of the gradient. All dogs in group 2 and 1 dog in group 3 were studied 3 months later, and 1 dog in group 2 was also studied 6 months after the debanding procedure. The systolic pressure gradient fell from a mean of 54 to 18 mm Hg after the debanding procedure. There was no difference in the gradient after debanding in the balloon group compared to the surgical group.