Aortoseptal angle and pressure gradient reduction following balloon valvuloplasty in dogs with severe subaortic stenosis

Introduction: To determine the relationship between aortoseptal angle Echocardiography; (AoSA) and the short- and long-term systolic pressure gradient (PG) reduction folAngiography; lowing combined cutting and high-pressure balloon valvuloplasty (CB/HPBV) in dogs Aortic stenosis; with severe subaortic stenosis. Congenital; Animals: Retrospective study of 22 client-owned dogs of various breeds with Cardiovascular severe subaortic stenosis (mean left ventricular to aortic PG = 143 mmHg; range = 80-322 mmHg) that underwent CB/HPBV. Materials and methods: Initial angiographic and left apical and right-sided parasternal long-axis view echocardiographic video loops were used for measuring the angle between the plane of the interventricular septum and the longitudinal axis of the ascending aorta. The PG reduction ratio immediately after CB/HPBV and 6 and 12 months later were compared with AoSA. Results: Weak correlations were observed for all instances of PG reduction ratio and AoSA type. Significantly greater mean differences of PG reduction ratio were observed for angles >160 degrees than for angles <160 degrees at 24 h (>160 degrees mean: 54.45, standard error [SE]: +/- 3.8; <160 degrees mean: 39.88, SE: +/- 2.09), 6 months (>160 degrees mean: 57.73, SE: +/- 10.9; <160 degrees mean: 28.22, SE: +/- 3.42), and 12 months (>160 degrees mean: 76.11, SE: +/- 17.5; <160 degrees mean: 27.61, SE: +/- 6.44; p=0.003). Conclusions: Dogs with AoSA >160 degrees on right-sided parasternal long-axis view echocardiograms responded with a greater PG reduction following CB/HPBV than did dogs with AoSA <160 degrees. This suggests that AoSA is associated with long-term outcomes of CB/HPBV, and measurement could help in the evaluation of dogs that are candidates for CB/HPBV. Crown Copyright (C) 2016 Published by Elsevier B.V. All rights reserved.