Table 2.

LVOT geometry, stroke volume index, and aortic valve area of all study patients and a subset of patients with cardiac CT available, stratified by different imaging methods.

All study patients (n=134)	Standard TTE	Biplane TTE	p-value
LVOT AP diameter (cm)	2.18 (2.00–2.30)	2.09 (1.96–2.28)	0.002
LVOT ML diameter (cm)	--	2.49 (2.35–2.68)	--
Eccentricity index	--	1.19 ± 0.11	--
LVOT area (cm2)	3.73 (3.14–4.15)	4.20 (3.66–4.90)	<0.001
Stroke volume index (ml/m2)	46 ± 12	54 ± 13	<0.001
Aortic valve area (cm2)	0.98 (0.81–1.17)	1.14 (0.94–1.37)	<0.001
Subset of patients with cardiac CT (n=30)	Standard TTE	Biplane TTE	Cardiac CT
LVOT AP diameter (cm)	2.15 (2.00–2.20) ‡	2.04 (1.94–2.12) †	2.11 (1.94–2.28)
LVOT ML diameter (cm)	--	2.43 (2.30–2.64) *	2.67 (2.54–2.88)
Eccentricity index	--	1.21 ± 0.10 †	1.28 ± 0.10
LVOT area (cm2)	3.63 (3.14–3.80) *	3.92 (3.56–4.37) †	4.38 (3.80–4.98)
Stroke volume index (ml/m2)	44 ± 9 *	51 ± 12 †	56 ± 13
Aortic valve area (cm2)	0.78 (0.66–0.88) *	0.94 (0.73–1.00) †	0.95 (0.84–1.15)

AP: anteroposterior; CT: computed tomography; LVOT: left ventricular outflow tract; ML: mediolateral; TTE: transthoracic echocardiography. Continuous variables are presented as mean ± standard deviation if normally distributed, and as median with interquartile range if non-normally distributed.

^*p < 0.001 vs CT

^†p < 0.01 vs CT

^‡p = non-significant vs CT