Baseline echocardiographic characteristics of the total study population and group of patients with normal and low SVI
| Variables | Total, n=1671 | Normal SVI, n=1292 | Low SVI, n=379 | p Value |
| Stroke volume (mL) | 85±26 | 93±23 | 57±9 | <0.001 |
| Stroke index (mL/m2) | 45±13 | 49±11 | 30±4 | <0.001 |
| Ejection fraction (%) | 66±7 | 67±6 | 66±7 | 0.042 |
| Stress-corrected midwall shortening (%) | 99±20 | 100±20 | 99±19 | 0.623 |
| LV mass (g) | 193±67 | 196±68 | 185±61 | 0.005 |
| LV mass index (g/m2.7) | 45.6±14.5 | 46.0±14.8 | 44.0±13.3 | 0.015 |
| Relative wall thickness | 0.36±0.09 | 0.36±0.09 | 0.35±0.09 | 0.226 |
| LV hypertrophy (%) | 35 | 37 | 31 | 0.028 |
| Peak jet velocity (m/s) | 3.1±0.5 | 3.1±0.5 | 3.0±0.5 | <0.001 |
| Mean aortic gradient (mm Hg) | 23±7 | 23±9 | 22±8 | 0.004 |
| Aortic valve area (cm) | 1.28±0.47 | 1.39±0.46 | 0.91±0.28 | <0.001 |
| Aortic valve are index (cm/m2) | 0.67±0.23 | 0.73±0.23 | 0.48±0.14 | <0.001 |
| Energy loss (cm) | 1.71±0.92 | 1.88±0.93 | 1.12±0.55 | <0.001 |
| Energy loss index (cm/m2) | 0.90±0.47 | 0.99±0.47 | 0.59±0.27 | <0.001 |
| Energy loss index <0.6 cm/m2 (%) | 21 | 13 | 61 | <0.001 |
| Inconsistently graded aortic valve stenosis | 28 | 17 | 63 | <0.001 |
| Aortic annulus diameter (cm) | 2.19±0.27 | 2.25±0.25 | 2.00±0.21 | <0.001 |
| Aortic root dimension (cm/m) | 3.9±0.6 | 3.9±0.6 | 3.8±0.6 | 0.029 |
| Small aortic root (%) | 17 | 17 | 20 | 0.163 |
| Mitral regurgitation (%) | 48 | 48 | 47 | 0.741 |
LV, left ventricular; SVI, stroke volume index.