The ACVIM consensus statement definition of left ventricular enlargement in myxomatous mitral valve disease does not always represent left ventricular enlargement

• Published in: Journal of veterinary cardiology 2022-08, Vol.42, p.92-102
• Main Authors: Rishniw, M., Brown, D.
• Format: Article
• Language: English
• Subjects: Allometric scaling; canine; Cardiac mensuration; echocardiography
• ISSN: 1760-2734; 1875-0834
• DOI: 10.1016/j.jvc.2022.06.004

To determine how frequently the current criteria for left ventricular enlargement in dogs misclassify healthy dogs as having left ventricular enlargement; to examine the effect of breed on diastolic left ventricular normalized dimensions (LVIDDN); to propose appropriate scaling exponents and reference limits for dogs. Echocardiographic data from 1,124 healthy adult dogs, including 454 dogs weighing 10% of apparently healthy dogs as having left ventricular enlargement, with specific breeds being misclassified up to 50% of the time. However, with a scaling exponent of 0.33, a constant of 1.7 represented a normal left ventricular size in 97.5% of healthy dogs in both generic and non-conforming breeds. Left ventricular internal dimension in diastole normalized to bodyweight is breed-dependent. A constant of 1.7 with a scaling exponent of 0.294 does not always represent ventricular enlargement; a scaling exponent of 0.33, with breed-specific reference limits for breeds that fail to conform to allometric models of generic dogs, reduces the misclassification of healthy dogs as having left ventricular enlargement.