| | Twist (°) | LS (%) | B-A (cm) | MAPSE (cm) | CTor (°/cm) | TorI (°/cm) | Combined deformation parameter | LVEF (%) |
|---|
DP (° x %) | DefI (° / %) |
|---|
Basal | 20 | −14 | 8 | 0.9 | 2.5 (N) | 22.2 (↑) | − 280 (↓) | − 1.4 (↑) | 55% |
1 year | 15 | −10 | 8 | 0.7 | 1.8 (↓) | 21.4 (↑) | − 150 (↓) | − 1.5 (↑) | 55% |
2 years | 8 | −8 | 8 | 0.6 | 1.0 (↓) | 13.3 (N) | −64 (↓) | −1 (N) | 48% |
3 years | 5 | −7 | 8 | 0.5 | 0.6 (↓) | 10.0 (↓) | −35 (↓) | −0.7 ↓ | 35% |
- From the beginning and throughout follow-up a low DP is an indicator of myocardial dysfunction, with normal LVEF. In the baseline diagnosis, a greater TorI and DefI are observed (with respect to the normal values in Table 2), reflecting an increase in myocardial torsion, which compensates to maintain the LVEF. This is not detected by the CTor measure, which appears normal. As the disease progresses, the normalization and subsequent diminishing of TorI and DefI are accompanied by lower LVEF, which reflects the exhaustion of the compensating mechanism. CTor shows less sensitivity in the detection of systolic dysfunction during follow-up
- LS Longitudinal Strain, B-A Base-Apex distance, MAPSE Mitral annular plane systolic excursion, T Twist, CTor Classic Torsion, TorI Torsion Index, DP Deformation Product, DefI Deformation Index, LVEF Left Ventricular Ejection Fraction, N normal
- ↑: Increased, ↓: Diminished
