Table 2.
Differences, derived by least square mean (LSM) (95% confidence intervals), of centrally quantified echocardiographic parameters between cases and controls as a function of time prior to the index time point (i.e., cardiomyopathy diagnosis)*
| ≥6 years prior to index | 4 to <6 years Prior to index | 2 to <4 years prior to index | <2 years prior to index | Index timepoint | All times prior to index | >2 years prior to index | |
|---|---|---|---|---|---|---|---|
| LV Systolic Function | |||||||
| 2D derived FS, % | 4.0 (1.2, 6.7) p=0.005 | 3.1 (0.7, 5.5) p=0.013 | 2.8 (0.7, 4.8) p=0.008 | 3.0 (1.0, 4.8) p=0.003 | 8.4 (6.7, 10.1) p<0.001 | 3.2 (1.9, 4.5) p<0.001 | 3.3 (1.7, 4.8) p<0.001 |
| Biplane EF, % | 2.8 (−3.2, 8.8) p=0.364 | 2.8 (−1.4, 7.0) p=0.194 | 4.8 (1.5, 8.1) p=0.006 | 4.6 (1.6, 7.6) p=0.004 | 12.4 (9.8, 15.0) p<0.001 | 3.7 (1.3, 6.1) p=0.003 | 3.5 (0.5, 6.4) p=0.023 |
| Mitral S’ TDI, m/sec | −0.005 (−0.025, 0.015) p=0.602 | 0.003 (−0.013, 0.019) p=0.700 | 0.007 (−0.007, 0.021) p=0.316 | 0.007 (−0.004, 0.018) p=0.193 | 0.027 (0.017, 0.038) p<0.001 | 0.003 (−0.005, 0.011) p=0.469 | 0.002 (−0.009, 0.012) p=0.745 |
| Septal S’ TDI, m/sec | −0.005 (−0.014, 0.003) p=0.234 | 0.003 (−0.004, 0.010) p=0.406 | 0.003 (−0.004, 0.009) p=0.421 | −0.003 (−0.008, 0.003) p=0.366 | 0.012 (0.007, 0.017) p<0.001 | −0.001 (−0.004, 0.003) p=0.778 | 0.000 (−0.004, 0.005) p=0.952 |
| LV Diastolic Function | |||||||
| Mitral PW E/A ratio | 0.59 (0.21, 0.96) p=0.002 | 0.07 (−0.27, 0.40) p=0.699 | 0.45 (0.16, 0.74) p=0.002 | 0.24 (−0.02, 0.50) p=0.069 | 0.56 (0.32, 0.80) p<0.001 | 0.34 (0.16, 0.51) p<0.001 | 0.37 (0.16, 0.58) p<0.001 |
| Mitral E’ (m/sec) | 0.014 (−0.018, 0.046); p=0.405 | 0.004 (−0.022, 0.029) p=0.784 | 0.013 (−0.010, 0.036) p=0.268 | −0.001 (−0.017, 0.016) p=0.930 | 0.045 (0.029, 0.061) p<0.001 | 0.007 (−0.007, 0.021) p=0.307 | 0.010 (−0.007, 0.027) p=0.257 |
| Mitral E/E’ ratio | 0.10 (−1.62, 1.81) p=0.913 | −0.38 (−1.69, 0.93) p=0.567 | 0.06 (−1.23, 1.35) p=0.927 | −0.26 (−1.15, 0.62) p=0.560 | −0.77 (−1.63, 0.08) p=0.078 | −0.12 (−0.92, 0.67) p=0.762 | −0.08 (−1.04, 0.89) p=0.878 |
| Septal E’ TDI, m/sec | −0.018 (−0.035, −0.002) p=0.032 | 0.010 (−0.004, 0.023) p=0.150 | 0.008 (−0.004, 0.021) p=0.192 | −0.002 (−0.013−0.009) p=0.751 | 0.018 (0.009, 0.028) p<0.001 | 0.000 (−0.008, 0.007) p=0.918 | 0.000 (−0.009, 0.009) p=0.991 |
| Septal E/E’ ratio | 1.74 (0.33, 3.16) p=0.016 | −0.46 (−1.61, 0.69) p=0.431 | −0.26 (−1.35, 0.83) p=0.639 | −0.16 (−1.09, 0.76) p=0.729 | −0.07 (−0.90, 0.76) p=0.867 | 0.21 (−0.46, 0.89) p=0.533 | 0.34 (−0.47, 1.15) p=0.413 |
| LV Combined Systolic/Diastolic Function | |||||||
| PW Doppler−derived MPI | 0.006 (−0.036, 0.048) p=0.788 | −0.030 (−0.065, 0.004) p=0.088 | −0.032 (−0.064, 0.001) p=0.055 | −0.026 (−0.055, 0.003) p=0.084 | −0.061 (−0.088, −0.034) p<0.001 | −0.021 (−0.039, −0.003) p=0.026 | −0.019 (−0.041, 0.003) p=0.093 |
| >6 years prior to index | 4 to <6 years Prior to index | 2 to <4 years prior to index | <2 years prior to index | Index timepoint | All times prior to index | >2 years prior to index | |
| TDI−derived MPI | 0.020 (−0.043, 0.084) p=0.536 | −0.042 (−0.091, 0.008) p=0.100 | −0.032 (−0.075, 0.011) p=0.144 | 0.001 (−0.041, 0.043) p=0.962 | −0.063 (−0.101, −0.026) p=0.001 | −0.013 (−0.042, 0.016) p=0.374 | −0.018 (−0.053, 0.017) p=0.314 |
| LV Size and Geometry | |||||||
| Posterior wall thickness, z-score | −0.26 (−0.81, 0.30) p=0.364 | −0.11 (−0.58, 0.35) p=0.628 | −0.16 (−0.57, 0.25) p=0.437 | −0.03 (−0.39, 0.33) p=0.867 | 0.10 (−0.21,0.41) p=0.532 | −0.14 (−0.42, 0.14) p=0.330 | −0.18 (−0.52, 0.16) p=0.305 |
| End diastolic dimension, z-score | −0.28 (−1.04, 0.47) p=0.462 | −0.87 (−1.49, −0.25) p=0.006 | −1.09 (−1.64, −0.55) p<0.001 | −0.81 (−1.31, −0.32) p=0.001 | −1.18 (−1.62, −0.74) p<0.001 | −0.77 (−1.19, −0.34) p<0.001 | −0.75 (−1.24, − 0.26) p=0.003 |
| Thickness to dimension ratio | −0.001 (−0.016, 0.014) p=0.864 | 0.005 (−0.008, 0.018) p=0.439 | 0.005 (−0.005, 0.016) p=0.321 | 0.006 (−0.004, 0.016) p=0.231 | 0.013 (0.004, 0.022) p=0.004 | 0.004 (−0.004, 0.011) p=0.323 | 0.003 (−0.006, 0.012) p=0.507 |
Abbreviations: 2D, two dimensional; EF, ejection fraction; FS, fractional shortening; LV, left ventricular; MPI, myocardial performance index; PW, pulsed wave Doppler derived; TDI, tissue Doppler imaging
Differences were based on comparisons of LSMs from longitudinal mixed models for each measure, including an interaction between case status and time period, using an autoregressive correlation structure between echocardiograms for the same patient. For example, at the index time point, the estimated FS is 8.5% greater in controls, as compared to cases; at the <2 year time point, the estimated FS is 3.0% greater in controls as compared to cases.