. 2019 Jul 16;33(5):1909–1920. doi: 10.1111/jvim.15562

Table 3.

Scaling exponents and prediction intervals of normalized linear left heart chamber measurements

Echocardiographic chamber measurement	97.5 percentile	95 percentile	75 percentile	50 percentile	25 percentile	5 percentile	2.5 percentile	Scaling exponent
LVIDd^{2DE, Lx}	1.59	1.55	1.43	1.36	1.29	1.19	1.16	0.316
LVIDd^{2DE, Sx}	1.62	1.57	1.45	1.37	1.30	1.20	1.16	0.316
LVIDd^{MM, Sx}	1.64	1.60	1.48	1.40	1.33	1.23	1.20	0.299
LVIDs^{2DE, Lx}	1.11	1.07	0.96	0.89	0.82	0.73	0.71	0.351
LVIDs^{2DE, Sx}	0.97	0.92	0.80	0.73	0.66	0.58	0.55	0.392
LVIDs^{MM, Sx}	0.96	0.92	0.80	0.73	0.66	0.57	0.55	0.387
LAD^{2DE, Lx}	1.57	1.53	1.43	1.37	1.30	1.22	1.19	0.309

Notes: Scaling exponents permit the prediction of normalized echocardiographic linear measurements (in cm) for any body weight (in kg) using the rearranged allometric equation: a = Y/x ^b and the desired prediction interval can be consulted to aid clinical decisions. For example, the LVIDd (MM, Sx) normalized for body weight for 95% of healthy dogs is predicted to be 1.20‐1.64. The equation used to normalize LVIDd (MM, Sx) for any body weight is the measured LVIDd (MM, Sx) / body weight^0.299. See Table 1 for the abbreviations key.