Immediate outcomes of low-pressure balloon valvuloplasty for severe pulmonary valve stenosis in 20 dogs: a retrospective, single-center case series.

ABSTRACT

INTRODUCTION: The primary objective of this study was to describe the immediate post-procedural outcomes in dogs with severe pulmonary stenosis that were treated with low-pressure balloon valvuloplasty (BV) at a single institution. ANIMALS, MATERIALS AND METHODS: Retrospective case series; medical records of dogs that underwent BV performed with a balloon dilation catheter >20 mm in diameter and a burst pressure of less than 4 atm (atm) were retrospectively reviewed. Twenty animals were identified fitting the criteria. Pre-procedural and post-procedural echocardiograms and peri-procedural angiograms were reviewed. Procedural success was defined as greater than 50% reduction in echocardiographically derived transpulmonary systolic pressure gradient (TPPG) or post-procedural TPPG of less than 50 mmHg. RESULTS: The median percent reduction from initial TPPG was 53% (range = 15-90%). Sixty percent of the dogs met the pre-specified criteria for a successful outcome. Post-procedural TPPG was not different based on valve types A or B (p=0.67), presence or absence of additional supravalvular (p=0.23) or subvalvular (p=0.83) obstructive components. DISCUSSION: The proportion of dogs that reach the successful outcome were not different based on valve type A or B. No relationship was noted between immediate outcomes and bodyweight or pulmonary annulus diameter. CONCLUSION: Dogs with severe pulmonic stenosis that underwent low-pressure BV had good immediate outcomes with no difference in outcome based on valve morphology. Further randomized controlled studies are needed to compare the outcomes of different strategies for BV in dogs with large-diameter pulmonary annulus.