Table 2. ECG findings at baseline, by disease stage compared to healthy subjects.
| Healthy controls | HAT stage 1 | HAT stage 2 | p-value | |
| N = 61 | N = 406 | N = 56 | ||
| ECG Intervals (msec; mean (SD)) | ||||
| PQ | 163 (16) | 159 (24) | 169 (25) | 0.008γ |
| QRS | 82 (11) | 80 (9) | 82 (8) | 0.076 |
| QTc | 403 (21) | 421 (28) | 423 (25) | <0.001α β |
| ECG Findings (%) | ||||
| atrial fibrillation/flutter | 0.0 | 0.3 | 0.0 | 0.862 |
| premature atrial capture | 1.6 | 0.5 | 0.0 | 0.450 |
| premature ventricular capture | 1.6 | 0.7 | 3.6 | 0.285 |
| bigeminus | 0.0 | 0.2 | 0.0 | 0.871 |
| AV block 1 | 3.3 | 3.7 | 7.1 | 0.449 |
| AV block 2 | 0.0 | 0.0 | 0.0 | 1.000 |
| RAH (Right atrial hypertrophy) | 0.0 | 1.7 | 1.8 | 0.334 |
| LAH (Left atrial hypertrophy) | 1.6 | 2.5 | 5.4 | 0.394 |
| RVH (Right ventricular hypertrophy) | 3.3 | 5.2 | 3.6 | 0.732 |
| LVH (Left ventricular hypertrophy) | 1.6 | 2.0 | 1.7 | 0.977 |
| pathologic Q | 0.0 | 1.0 | 0.0 | 0.551 |
| RBBB (Right bundle brunch block) | 0.0 | 1.0 | 0.0 | 0.581 |
| LBBB (Left bundle brunch block) | 1.6 | 0.0 | 0.0 | 0.011 |
| LAHB (Left anterior hemiblock) | 1.6 | 1.7 | 0.0 | 0.584 |
| RBBB and LAHB | 0.0 | 0.5 | 1.7 | 0.469 |
| repolarisation changes | 6.6 | 35.2 | 32.1 | <0.001α β |
| low voltage | 6.7 | 20.0 | 30.4 | 0.005α β γ |
| QTc prolongationa | 0 | 11.1 | 12.5 | 0.021α β |
| minor changes | 16.4 | 9.6 | 7.1 | 0.193 |
| major changes | 19.7 | 53.5 | 67.9 | <0.001α β γ |
a
for male >440 msec, female >460 msec
α: for healthy control vs HATstage 1 p<0.05
β: for healthy control vs HATstage 2 p<0.05
γ: for HAT stage 1 vs HATstage 2 p<0.05