Clinical characteristics, predicted genes, and genotypes of LQTS patients
| Genotype* | ||||
|---|---|---|---|---|
| Characteristic | KCNQ1 (n=10) | KCNH2 (n=18) | SCN5A (n=3) | No mutation (n=9) |
| *Based on mutation analysis. | ||||
| †0–9 y: KCNQ1 more probable, >9 y: KCNH2 or SCN5A probable, but other criteria more important for assignment. | ||||
| ‡More than one trigger/patient is possible. | ||||
| §Including noise. | ||||
| ¶Based on all phenotypic information. | ||||
| **Including one compound KCNQ1/SCN5A mutation carrier. | ||||
| ††Including one compound heterozygous KCNQ1 mutation carrier. | ||||
| ‡‡Including one homozygous KCNQ1 mutation carrier. | ||||
| §§Including one homozygous KCNH2 mutation carrier. | ||||
| Age of onset† | ||||
| 0–9 y | 5†† | 3§§ | – | 2 |
| >9 y | 5**/‡‡ | 15 | 3 | 7 |
| Triggers‡ | ||||
| Exercise | 9††/‡‡ | 6 | – | 5 |
| Swimming | 5†† | – | – | 2 |
| Emotion | 2††/‡‡ | 4 | – | – |
| Arousal§ | – | 10 | – | 2 |
| Quiescence | 1** | 6 | 3 | 2 |
| Other | – | 2§§ | – | 1 |
| ECG morphology | ||||
| KCNQ1-like | 8** | 4 | 1 | 3 |
| KCNH2-like | 1†† | 14§§ | 1 | 6 |
| SCN5A-like | 1‡‡ | – | 1 | – |
| Predicted gene to be mutated¶ | ||||
| KCNQ1 | 10**/††/‡‡ | 1 | – | 4 |
| KCNH2 | – | 17§§ | 2 | 4 |
| SCN5A | – | – | 1 | 1 |