TABLE 1.
| Total Participants | Competitive Sports | Recreational Sports | Physical Education | |
|---|---|---|---|---|
| Number of patients | 103 | 26 | 77 | 84 |
| Age at diagnosis, yrs | 8.4 ± 5.6 | 9.3 ± 4.5 | 8.0 ± 5.6 | 7.4 ± 4.8 |
| Age at follow-up, yrs | 15.4 ± 5.1 | 16.2 ± 3.0 | 15.4 ± 5.5 | 14.0 ± 3.7 |
| Percent female | 51 | 58 | 45 | 50 |
| Average QTc, ms | 468 ± 42 | 461 ± 35 | 470 ± 43 | 466 ± 42 |
| QTc 25th percentile, ms | 442 | 436 | 449 | 440 |
| QTc 75th percentile, ms | 484 | 481 | 484 | 483 |
| Genotype positive, phenotype negative | 43 (42) | 13 (50) | 46 (45) | 36 (44) |
| Gene mutations | 105 | 26 | 79 | 84 |
| KCNQ1 | 60 (58) | 15 (58) | 46 (58) | 48 (57) |
| KCNH2 | 36 (35) | 8 (31) | 25 (32) | 31 (37) |
| SCN5A | 6 (6) | 1 (4) | 5 (6) | 3 (4) |
| KCNE1 | 1 (1) | 1 (4) | 1 (1) | 0 (0) |
| KCNE2 | 2 (2) | 1 (4) | 2 (3) | 2 (2) |
| >1 Genotype (included above) | 2 (2) | 0 | 2 (3) | 2 (2) |
| Beta-blockers | 101 (98) | 26 (100) | 75 (97) | 82 (100) |
| Personal AED | 36 (36) | 15 (58) | 21 (27) | 30 (36) |
| ICD | 6 (6) | 2 (8) | 5 (6) | 6 (7) |
| Noncompliance | 3 (3) | 2 (8) | 2 (3) | 2 (2) |
| Known follow-up, yrs | 7.1 ± 4.0 | 6.9 ± 4.1 | 7.3 ± 3.9 | 6.6 ± 4.0 |
| LQTS cardiac events during participation | 0 (0)* | 0 (0) | 0 (0) | 0 (0) |
Values are mean ± SD or n (%).
*
There were no long QT syndrome (LQTS) cardiac events during sports participation. However 1 patient had an appropriate implantable cardioverter-defibrillator (ICD) shock while running casually in the backyard when she was noncompliant with beta-blockers.
AED = automated external defibrillator.