Department of Clinical Pathology, Faculty of Veterinary Medicine, Okayama University of Science, 1-3 Ikoinooka, Imabari-shi, Ehime 794-8555, Japan.
Laboratory of Veterinary Internal Medicine II, Nippon Veterinary and Life Science University, 1-7-1 Kyonan-cho, Musashino-shi, Tokyo 180-8602, Japan.
J Vet Cardiol. 2020 Aug;30:92-99. doi: 10.1016/j.jvc.2020.06.001. Epub 2020 Jun 23.
INTRODUCTION/OBJECTIVES: The American College of Veterinary Internal Medicine (ACVIM) guidelines suggest that pimobendan should be initiated in dogs which meet all criteria of stage B2 myxomatous mitral valve disease (MMVD): murmur intensity ≥ 3/6, left atrial-to-aortic ratio ≥ 1.6, normalized left ventricular internal diameter in diastole ≥ 1.7, and vertebral heart size > 10.5. Recently, a new radiographic index for left atrial enlargement, vertebral left atrial size (VLAS), was proposed. The objective of the present study was to evaluate whether VLAS is useful in staging MMVD and if it can distinguish between ACVIM stages B1 and B2.
Ninety-seven client-owned dogs with MMVD were evaluated and classified as ACVIM stage B1, B2, or C-D.
The echocardiographs and radiographs of all the dogs were retrospectively evaluated to obtain left atrial-to-aortic ratio, normalized left ventricular internal diameter in diastole, and VLAS values. The data were analyzed to assess the correlation between these measurements and VLAS, and the optimal cutoff value of VLAS was determined.
A VLAS cutoff value of 2.6 provided the greatest diagnostic accuracy for identification of dogs with ACVIM stage B2 MMVD (area under the curve, 0.96; sensitivity, 95%; specificity, 84%). A VLAS ≥2.5 exhibited the highest sensitivity (sensitivity, 100%; specificity, 78%), and a VLAS ≥ 3.1 exhibited the highest specificity (sensitivity, 47%; specificity, 100%).
VLAS is a helpful index for monitoring MMVD using radiography. A VLAS cutoff value of 2.5 could be used to identify dogs that may benefit from echocardiography to determine if they have reached ACVIM stage B2.
简介/目的：美国兽医内科协会（ACVIM）指南建议，在满足以下所有 B2 期黏液瘤性二尖瓣疾病（MMVD）标准的犬中，应开始使用匹莫苯丹：杂音强度≥3/6，左心房至主动脉比≥1.6，正常舒张期左心室内径≥1.7，以及脊椎心脏大小>10.5。最近，提出了一种用于评估左心房扩大的新放射学指数，即椎骨左心房大小（VLAS）。本研究的目的是评估 VLAS 是否有助于 MMVD 分期，以及它是否可以区分 ACVIM 分期 B1 和 B2。
评估了 97 只患有 MMVD 的患犬，并将其分类为 ACVIM 分期 B1、B2 或 C-D。
回顾性评估所有犬的超声心动图和 X 光片，以获取左心房至主动脉比、正常舒张期左心室内径和 VLAS 值。分析数据以评估这些测量值与 VLAS 之间的相关性，并确定 VLAS 的最佳截断值。
VLAS 截断值为 2.6 时，对识别患有 ACVIM 分期 B2 MMVD 的犬具有最大的诊断准确性（曲线下面积为 0.96；敏感性为 95%；特异性为 84%）。VLAS≥2.5 具有最高的敏感性（敏感性为 100%；特异性为 78%），VLAS≥3.1 具有最高的特异性（敏感性为 47%；特异性为 100%）。
VLAS 是一种通过 X 光监测 MMVD 的有用指数。VLAS 截断值为 2.5 可用于识别可能受益于超声心动图以确定是否达到 ACVIM 分期 B2 的犬。
