. Author manuscript; available in PMC: 2015 Feb 23.

Published in final edited form as: Echocardiography. 2013 Sep 19;31(3):375–384. doi: 10.1111/echo.12351

Table III. Conventional Echocardiographic Measurements.

	Age (weeks)

	3	5	7	11	P-value
Morphometric parameters
Body weight (g)	7.8 ± 0.3	18.3 ± 1.2^*	20.7 ± 1.0^*	24.5 ± 2.0^*	<0.01
Tibia length (mm)	11.3 ± 0.1	14.8 ± 0.2^*	16.1 ± 0.1^*	16.1 ± 0.9^*	<0.01
LV mass (mg) (necropsy)	27 ± 1	61 ± 4^*	72 ± 6^*	84 ± 7^*	<0.01
LV mass (mg) (ECHO^†)	28.4 ± 5.9	41.9 ± 6.8	73.7 ± 12.7	79.8 ± 18.2	<0.01
Conventional echocardiographic measurements
Ejection fraction (%)	75 ± 1	70 ± 3	60 ± 1^*	61 ± 2^*	<0.01
Fractional shortening (%)	44 ± 1	39 ± 2	33 ± 2^*	34 ± 2^*	<0.01
LVEDD (mm)	2.7 ± 0.1	3.5 ± 0.1^*	4.3 ± 0.1^*	4.0 ± 0.2^*	<0.01
LVESD (mm)	1.5 ± 0.04	2.1 ± 0.10^*	2.9 ± 0.1^*	2.7 ± 0.2^*	<0.01
LVPWd (mm)	0.4 ± 0.04	0.5 ± 0.04	0.6 ± 0.03^*	0.6 ± 0.02^*	<0.01

LV = left ventricle; LVEDD = left ventricle end-diastolic dimension; LVESD = left ventricular end-systolic dimension; LVPWd = left ventricular posterior wall thickness.

P < 0.01 as compared to 3 weeks.

^†

LV mass calculated from echocardiographic measurements.