Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, 14853, Ithaca, NY, USA; Veterinary Information Network, Davis, CA, 95616, USA.
Department of Veterinary Medicine, University of Sassari, Via Vienna 2, 07100, Sassari, Italy.
J Vet Cardiol. 2021 Feb;33:69-75. doi: 10.1016/j.jvc.2020.12.001. Epub 2020 Dec 24.
Clinicians measure left ventricular dimensions in dogs from both M-mode and two-dimensional images. Little information currently exists as to whether these two methods provide measurements similar enough to be interchangeable.
The animals included in this study are 206 client-owned dogs: 68 healthy, 105 with myxomatous mitral valve disease, 33 with other cardiac or extracardiac disease.
Investigators measured left ventricular diastolic and systolic dimensions from archived M-mode and two-dimensional images obtained from the right parasternal short-axis view. Agreement between the pairs of measurements was examined using limits of agreement (Bland-Altman) plots.
Left ventricular diastolic dimensions showed no fixed or proportional bias but did show heteroscedasticity. Ninety-five percent limits of agreement for normalized differences approximated ±10%; 95% of the absolute differences for any pair of measurements were <3.9 mm regardless of bodyweight and <2.7 mm for dogs <15 kg. Left ventricular systolic dimensions showed slight proportional bias, with two-dimensional measurements being progressively larger than M-mode measurements as ventricular size increased. Ninety-five percent limits of agreement for normalized differences approximated ±20%; 95% of the absolute differences for any pair of measurements were <4.6 mm regardless of bodyweight and <3.5 mm for dogs <15 kg. Mitral valve disease did not appreciably affect these findings.
Left ventricular internal dimensions in dogs with and without cardiac disease measured from two-dimensional right parasternal short-axis images are interchangeable with those measured from M-mode images using the same view.
临床医生通过 M 型和二维图像测量犬的左心室尺寸。目前关于这两种方法提供的测量值是否足够相似以相互替换的信息很少。
本研究包括 206 只患犬：68 只健康犬，105 只患有黏液瘤性二尖瓣疾病，33 只患有其他心脏或心脏外疾病。
研究人员从右胸骨旁短轴视图获得的存档 M 型和二维图像中测量左心室舒张和收缩尺寸。使用一致性界限（Bland-Altman）图检查测量值对之间的一致性。
左心室舒张尺寸没有固定或比例偏差，但存在异方差。归一化差异的 95%一致性界限接近±10%；无论体重如何，任何一对测量值的绝对差异的 95%都<3.9mm，对于<15kg 的犬<2.7mm。左心室收缩尺寸显示出轻微的比例偏差，随着心室大小的增加，二维测量值比 M 模式测量值逐渐增大。归一化差异的 95%一致性界限接近±20%；无论体重如何，任何一对测量值的绝对差异的 95%都<4.6mm，对于<15kg 的犬<3.5mm。二尖瓣疾病并没有明显影响这些发现。
在患有和不患有心脏病的犬中，从二维右胸骨旁短轴图像测量的左心室内部尺寸与使用相同视图从 M 模式图像测量的尺寸可互换。
