Table 3.
ECG findings
| Total population (n = 11 949) | Nonathletes (n = 4548) (A) | Noncompetitive athletes (n = 4.946) (B) | Competitive athletes (n = 2455) (C) | |||||||||
| ECG finding | n | % | n | % | n | % | n | % | P-value | P-value (A vs. B) | P-value (A vs. C) | P-value (B vs. C) |
| Major abnormalities | ||||||||||||
| T-wave inversion/ST-segment depression | 422 | 3.5 | 178 | 3.9 | 170 | 3.4 | 74 | 3.0 | 0.135 | – | – | – |
| Complete left bundle branch block | 1 | 0.0 | 0 | 0.0 | 1 | 0.0 | 0 | 0.0 | 0.493 | – | – | – |
| Complete right bundle branch block | 203 | 1.7 | 61 | 1.3 | 101 | 2 | 41 | 1.7 | 0.030 | 0.032 | 0.965 | 0.94 |
| Left anterior fascicular block/left posterior fascicular block | 26 | 0.2 | 9 | 0.2 | 14 | 0.3 | 3 | 0.1 | 0.352 | – | – | – |
| Left/right atrial enlargement | 239 | 2 | 124 | 2.7 | 83 | 1.7 | 32 | 1.3 | <0.001 | <0.001 | <0.001 | 0.779 |
| Left axis deviation | 100 | 0.8 | 36 | 0.8 | 42 | 0.8 | 22 | 0.9 | 0.893 | – | – | – |
| Right axis deviation | 315 | 2.6 | 132 | 2.9 | 119 | 2.4 | 64 | 2.6 | 0.319 | – | – | – |
| Ventricular preexcitation (WPW) | 12 | 0.1 | 4 | 0.1 | 7 | 0.1 | 1 | 0.04 | 0.412 | – | – | – |
| Long QT interval | 56 | 0.5 | 20 | 0.4 | 20 | 0.4 | 16 | 0.7 | 0.319 | – | – | – |
| Short QT interval | 127 | 1.1 | 49 | 1.1 | 43 | 0.9 | 35 | 1.4 | 0.089 | – | – | – |
| Brugada-like ECG pattern | 97 | 0.8 | 68 | 1.5 | 19 | 0.4 | 10 | 0.4 | <0.001 | <0.001 | <0.001 | 1 |
| Premature ventricular contractions | 60 | 0.5 | 32 | 0.7 | 18 | 0.4 | 10 | 0.4 | 0.049 | 0.096 | 0.512 | 1 |
| Left ventricular hypertrophy | 241 | 2.0 | 81 | 1.8 | 90 | 1.8 | 70 | 2.9 | 0.004 | 1 | 0.013 | 0.016 |
| Right ventricular hypertrophy | 30 | 0.3 | 8 | 0.2 | 14 | 0.3 | 8 | 0.3 | 0.411 | – | – | – |
| Minor abnormalities | ||||||||||||
| First degree AV block | 33 | 0.3 | 19 | 0.4 | 9 | 0.2 | 5 | 0.2 | 0.068 | – | – | – |
| Short PQ interval | 310 | 2.6 | 136 | 3.0 | 132 | 2.7 | 42 | 1.7 | 0.005 | 1 | 0.005 | 0.039 |
| Rhythm sinus coronary | 61 | 0.5 | 19 | 0.4 | 26 | 0.5 | 16 | 0.7 | 0.415 | – | – | – |
| Junctional rhythm | 25 | 0.2 | 7 | 0.2 | 13 | 0.3 | 5 | 0.2 | 0.509 | – | – | – |
| Atrial premature beats | 117 | 1.0 | 47 | 1.0 | 48 | 1.0 | 22 | 0.9 | 0.854 | – | – | – |
| Sinus bradycardia | 578 | 4.8 | 127 | 2.8 | 226 | 4.6 | 225 | 9.2 | <0.001 | <0.001 | <0.001 | <0.001 |
| Sinus tachycardia | 632 | 5.3 | 333 | 7.3 | 226 | 4.6 | 73 | 3 | <0.001 | <0.001 | <0.001 | 0.004 |
| Incomplete right bundle branch block | 1878 | 15.7 | 918 | 20.2 | 625 | 12.6 | 335 | 13.6 | <0.001 | <0.001 | <0.001 | 0.714 |
| Early repolarization | 589 | 4.9 | 232 | 5.1 | 197 | 4.0 | 160 | 6.5 | <0.001 | 0.03 | 0.048 | <0.001 |
| Sinus arrhythmia | 2291 | 19.2 | 1.084 | 23.8 | 817 | 16.5 | 390 | 15.9 | <0.001 | <0.001 | <0.001 | 1 |
ECG abnormalities presented in Table 1 were not reported if no cases were founded. Post hoc analysis results presented in case of overall P-value less than 0.05.