Body weight had a significant independent effect on two-dimensional echocardiographic variables in healthy cats, demonstrating that allometric scaling and body weight-based 95% prediction intervals should be preferred over conventional reference intervals.
Observational (n=150)
No
Does allometric scaling improve the accuracy of echocardiographic reference intervals in healthy cats?
Allometric scaling and body weight-based 95% prediction intervals should be preferred over conventional 2D echocardiographic reference intervals in cats to avoid misdiagnosis, particularly during screening for hypertrophic cardiomyopathy.
p-value: p=<0.05
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 × Mb) reference intervals and prediction intervals were determined. BW had a significant (P6 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.
Karsten et al. (2017) conducted an observational in Healthy (n=150). Allometric scaling vs. Conventional reference intervals was evaluated on Effect of body weight on 2D echocardiographic variables (p=<0.05). Body weight had a significant independent effect on two-dimensional echocardiographic variables in healthy cats, demonstrating that allometric scaling and body weight-based 95% prediction intervals should be preferred over conventional reference intervals.