Table 1.

Tissue Doppler velocities, strain and strain rate- normal RV value.

	Neonates/ infants	Children	Adults	Intra-observer variability	Inter-observer variability	References
TDI						Kukulski (18) Eidem (125)
S’ (basal)	10.2 ± 5.5 PTDI	12.8 (10.7-16.5) 16.1 ±4.7 PTDI	15.2 ± 2.8 PTDI	6.17 (COV)	8.82 (COV)
E’(basal)	13.8 ± 8.2 PTDI	-16.2 (-12.6 to -21.1) PTDI	14.5 ± 3.5 PTDI	2.2% - 3.4% (mean % difference)	1.6% - 2.0% (mean % difference)
A’(basal)	9.8 ± 2.4 PTDI	−8.6 (−5.5 to −12.1) PTDI	16.2 ± 3.1 PTDI
Strain				12.9 (mean % diff)	14.4 (mean % diff)	Weidemann (40) Pena (42)
Basal	−28.38 ± .90 CTDI	−36 ± 11 CTDI	19±6	NA	NA
Mid	−33.20 ± .34 CTDI	−45 ± 13 CTDI	27±6	NA	NA
Apical	−31.95 ± 5.06 CTDI	−34 ± 11 CTDI	32±6	NA	NA
Strain rate				11.8 (mean % difference)	13.6 (mean % difference)	Weidemann (40) Pena (42)
Basal	−1.93 ± 0.52 CTDI	−2.4 ± 0.6 CTDI	1.5±0.41	NA	NA
Mid	−1.91 ± 0.45 CTDI	−2.8 ± 0.7 CTDI	1.72±0.27	NA	NA
Apical	−1.81± 0.40 CTDI	−2.5 ± 0.6 CTDI	2.04±0.41	NA	NA

The values in the table are shown as follows. For each age group the standard deviation (s) was taken to construct ranges of the mean ± 2s. Abbreviations: A’, peak late diastolic velocity, COV, coefficient of variation; CTDI, color tissue Doppler imaging, E’, peak early-diastolic velocity; NA, not available; PTDI, pulsed tissue Doppler imaging; S’, peak systolic velocity. Copyright from Mertens L, Friedberg MK, Nat. Rev. Cardiol 2010, (doi:10.1038/nrccardio.2010.118) with permission from the publisher, Macmillan Publishers Limited, Copyright © approval from Nature Publishing Group.