Independent predictors of immediate and long-term results after pulmonary balloon valvuloplasty in dogs

Objectives: Determine whether valve morphology, pulmonary annulus diameter, aortic/pulmonic annulus ratio, balloon-to-annulus ratio (BAR), pre-pulmonary balloon valvuloplasty (PBV), Doppler gradient, and residual Doppler gradient are independent predictors of immediate and long-term results after PBV in dogs as in humans. Animals, materials and methods: Retrospective study. Medical records of dogs that underwent PBV, from January 1999 to December 2008 were reviewed. All dogs with pre- and immediate (24 h) post-PBV echocardiographic examination were included. 126 dogs were selected. Immediate outcome was optimal when the dog survived the PBV and Doppler gradient was ≤50 mmHg. Long-term outcome (1 year) was optimal when the dog survived at least 1-year follow-up without symptoms and Doppler gradient was ≤50 mmHg. Results: Only pre-PBV Doppler gradient was identified as a significant independent predictor of immediate results (P < 0.001; OR 0.97, CI 0.96-0.98). Pre-PBV Doppler gradient and residual Doppler gradient were the only independent predictors of long-term results (P = 0.036; OR 0.98, CI 0.96-0.99 and P = 0.005; OR 0.95, CI 0.92-0.98, respectively). Conclusion: In dogs as in humans higher pre-PBV Doppler gradient is one of the most important independent predictor of suboptimal immediate and long-term results after PBV and must be considered before scheduling this procedure. Moreover higher valvar residual Doppler gradient is an important independent predictors of suboptimal long-term results.