Karsten Schober, Stephanie Savino, Vedat Yildiz
Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, 601 Vernon L Tharp Street, Columbus, OH 43210, U.S.A.
Center for Clinical and Translational Science, Wexner Medical Center, Main Campus, The Ohio State University, Columbus, OH, 43210, U.S.A.
J Vet Med Sci. 2017 Nov 10;79(11):1764-1771. doi: 10.1292/jvms.17-0250. Epub 2017 Oct 6.
The objective of the study was to evaluate the effects of body weight (BW), breed, and sex on two-dimensional (2D) echocardiographic measures, reference ranges, and prediction intervals using allometrically-scaled data of left atrial (LA) and left ventricular (LV) size and LV wall thickness in healthy cats. Study type was retrospective, observational, and clinical cohort. 150 healthy cats were enrolled and 2D echocardiograms analyzed. LA diameter, LV wall thickness, and LV dimension were quantified using three different imaging views. The effect of BW, breed, sex, age, and interaction (BW*sex) on echocardiographic variables was assessed using univariate and multivariate regression and linear mixed model analysis. Standard (using raw data) and allometrically scaled (Y=a × M) reference intervals and prediction intervals were determined. BW had a significant (P<0.05) independent effect on 2D variables whereas breed, sex, and age did not. There were clinically relevant differences between reference intervals using mean ± 2SD of raw data and mean and 95% prediction interval of allometrically-scaled variables, most prominent in larger (>6 kg) and smaller (<3 kg) cats. A clinically relevant difference between thickness of the interventricular septum (IVS) and dimension of the LV posterior wall (LVPW) was identified. In conclusion, allometric scaling and BW-based 95% prediction intervals should be preferred over conventional 2D echocardiographic reference intervals in cats, in particular in small and large cats. These results are particularly relevant to screening examinations for feline hypertrophic cardiomyopathy.
本研究的目的是利用健康猫左心房（LA）和左心室（LV）大小及LV壁厚度的异速生长缩放数据，评估体重（BW）、品种和性别对二维（2D）超声心动图测量、参考范围和预测区间的影响。研究类型为回顾性、观察性临床队列研究。纳入150只健康猫并分析其2D超声心动图。使用三种不同的成像视图对LA直径、LV壁厚度和LV尺寸进行量化。使用单变量和多变量回归以及线性混合模型分析评估BW、品种、性别、年龄和交互作用（BW*性别）对超声心动图变量的影响。确定了标准（使用原始数据）和异速生长缩放（Y = a×M）参考区间及预测区间。BW对2D变量有显著（P<0.05）独立影响，而品种、性别和年龄则无此影响。使用原始数据的均值±2SD以及异速生长缩放变量的均值和95%预测区间的参考区间之间存在临床相关差异，在较大（>6 kg）和较小（<3 kg）的猫中最为明显。确定了室间隔（IVS）厚度和LV后壁（LVPW）尺寸之间的临床相关差异。总之，在猫中，特别是在小型和大型猫中，异速生长缩放和基于BW的95%预测区间应优于传统的2D超声心动图参考区间。这些结果与猫肥厚性心肌病的筛查检查尤为相关。
