Table 5.

Heritability estimates of flow metrics in the ascending aorta.

Trait	QTDT ${\text{h}}^2$			GCTA SNP-based ${\text{h}}^2$
	P value	h2 (%)	n	P value	h2 (%)	n
Cross sectional area (${\text{mm}}^2$)	0.0019	36	317	0.0079	31	294
Diameter (m)	0.0094	29	319	0.0101	30	295
$U_{\mathit{pm}}$ (m/s)	0.007	36	311	0.0020	41	287
$U_{\mathit{max}}$ (m/s)	$>0.05$	16	298	$>0.05$	17	276
$R{e}_{\mathit{pm}}$	0.0012	41	302	0.0017	39	279
$R{e}_{\mathit{max}}$	$>0.05$	13	273	$>0.05$	12	253

Narrow-sense heritability estimates shown here were calculated using QTDT pedigree-based software and GCTA GREML-based software. P values that are not significant are identified here as $>0.05$. The traits, P value, heritability estimate as a percentage (${\text{h}}^2$), and the sample number (n) are shown. The number of samples differs by adjustment for covariates, and 10% of samples were not genotyped so heritability estimated by GCTA had a lower sample size.