Table 1.
Clinical characteristics, mutation types, and ECG parameters of the study populations from the AMC and the Mayo Clinic
| Variable | AMC | Mayo |
|---|---|---|
| Clinical characteristics | ||
| Patients, n (%) | 84 (100) | 84 (100) |
| Male/female, n | 34/50 | 38/46 |
| Age, years | 34 ± 3 | 27 ± 2 |
| Proband, n (%) | 22 (26) | 13 (15) |
| Family history for sudden death, n (%) | 40 (48) | 58 (69) |
| Syncope, n (%) | 18 (21) | 18 (21) |
| Documented TdP/VF, n (%) | 5 (6) | 1 (1) |
| Mutation type | ||
| Missense, n (%) | 63 (75) | 67 (80) |
| Frameshift, n (%) | 7 (8) | 1 (1) |
| Splice site, n (%) | 11 (13) | 4 (5) |
| Deletion, n (%) | 3 (4) | 12 (14) |
| ECG parameters | ||
| RR interval (ms) | 859 ± 19 | 917 ± 24 |
| Males | 879 ± 26 | 968 ± 41 |
| Females | 844 ± 28 | 875 ± 27 |
| QT duration (ms) | 411 ± 7 | 426 ± 6 |
| Males | 405 ± 8 | 429 ± 10 |
| Females | 416 ± 10 | 425 ± 8 |
| QTc (ms) | 446 ± 7 | 451 ± 4 |
| Males | 435 ± 6 | 445 ± 6 |
| Females | 454 ± 7a | 457 ± 4a |
aStatistical significance compared with males.
Values are expressed as number of patients (percentage of total), or as mean ± standard error of the mean (SEM).