Table 5. Correlations of torsion parameters with age and heart rate.
| Variables | Univariate p* | Multivariate p† | ||
|---|---|---|---|---|
| Age | Heart rate | Age | Heart rate | |
| Torsion parameters | ||||
| Peak basal rotation (deg/cm) | 0.003 | <0.001 | NS | 0.03 |
| Peak apical rotation (deg/cm) | 0.006 | <0.001 | NS | 0.012 |
| Peak basal rotation velocity (deg/s) | 0.016 | <0.001 | NS | <0.001 |
| Peak apical rotation velocity (deg/s) | NS | 0.005 | NS | 0.001 |
| Peak systolic torsion (deg/cm) | 0.003 | <0.001 | NS | 0.008 |
| Peak systolic twist velocity (deg/s) | NS | 0.001 | NS | 0.001 |
| Peak torsion velocity, (deg/s)/cm | <0.001 | <0.001 | NS | <0.001 |
| Peak untwisting velocity (deg/s) | 0.028 | 0.001 | NS | <0.05 |
| Peak untwisting velocity-N, (deg/s)/cm | <0.001 | <0.001 | NS | <0.001 |
| LV untwisting velocity during IVRT (deg/s) | NS | NS | NS | NS |
| Isovolumic untwisting recoil (%) | NS | NS | NS | NS |
| Isovolumic untwisting recoil rate (%/ms) | NS | NS | NS | NS |
| Events timing | ||||
| Time to peak early systolic torsion (% ST) | NS | NS | NS | NS |
| Time to peak twist (% ST) | NS | NS | NS | NS |
| Time to peak twist velocity (% ST) | NS | NS | NS | NS |
| Time to peak twist (% ST) | NS | NS | NS | NS |
| Time to peak twist velocity (% ST) | NS | NS | NS | NS |
| Time to peak untwisting velocity (% DT) | NS | 0.002 | NS | 0.001 |
*Bivariate correlation analysis, †Multivariate linear regression analysis. N: normalized by left ventricular length, IVRT: isovolumic relaxation time, ST: systolic time, DT: diastolic time, LV: left ventricular