Transthoracic two-dimensional and three-dimensional echocardiography for the measurement of mitral valve area planimetry in English Bull Terriers with and without heart disease.
INTRODUCTION
Mitral valve area (MVA) planimetry is used to diagnose and classify mitral stenosis (MS) in humans using two-dimensional and three-dimensional echocardiography (MVA2D and MVA3D). This study aimed to evaluate agreement, feasibility, and observer variability between MVA2D and MVA3D in English Bull Terriers (BT). Our hypotheses were (1) that the MVA of BT is generally smaller than that of breeds with similar body weight and (2) that these techniques could be used to diagnose MS in BTs.


ANIMALS
Twenty healthy BTs, 15 healthy Boxers, and 49 BTs with heart disease.


MATERIALS AND METHODS
A prospective diagnostic agreement study was conducted. All dogs underwent a thorough clinical examination, conventional transthoracic echocardiography, and three-dimensional echocardiography.


RESULTS
Bland-Altman plots (limits of agreement: 0.12-1.5) showed consistent bias and poor agreement between MVA2D and MVA3D. For the 69 BTs, MVA3D (2.1 ± 0.50 cm2) measurements were significantly lower than MVA2D measurements (2.9 ± 0.60 cm2), and healthy BTs had significantly lower MVA parameters than healthy Boxers (p < 0.001). Intraobserver and interobserver variability were excellent for both MVA2D and MVA3D (intraclass correlation coefficient >0.9). Six BTs were diagnosed with MS, with MVA3D less than 1.8 cm2 and a mean transmitral gradient (MTG) of more than 5 mmHg.


CONCLUSIONS
Both MVA2D and MVA3D are feasible, have low observer variability and can be used to diagnose MS in BTs. For assessing the narrowest orifice area, the preferred method is MVA3D. The smaller MVA in BTs compared to Boxers may indicate some degree of MS.
['Chompoosan|C|C|', 'Schrøder|A S|AS|', 'Bach|M B T|MBT|', 'Møgelvang|R|R|', 'Willesen|J L|JL|', 'Langhorn|R|R|', 'Koch|J|J|']
D000818:Animals D004283:Dog Diseases D004285:Dogs D019560:Echocardiography, Three-Dimensional D017548:Echocardiography, Transesophageal D008943:Mitral Valve D008946:Mitral Valve Stenosis D011446:Prospective Studies
Mitral stenosis Boxer Canine Mitral valve orifice