SQTI group (n = 34) | Normal QT group (n = 136) | P | |
---|---|---|---|
Demographics | |||
Age (year) | 23.5 (21.0–30.5) | 23.5 (21.0–31.0) | > 0.999 |
Male | 31 (91.2) | 124 (91.2) | > 0.999 |
Family history of SCA | 1 (2.9) | 0 (0.0) | 0.200 |
Height (cm) | 173.0 (170.0–176.8) | 173.0 (168.0–177.0) | 0.698 |
Weight (kg) | 66.2 (61.1–72.0) | 69.5 (60.0–78.8) | 0.155 |
Systolic BP (mmHg) | 124.0 (113.3–129.0) | 122.0 (113.3–134.0) | 0.537 |
Diastolic BP (mmHg) | 71.0 (66.0–78.0) | 76.0 (67.3–83.0) | 0.056 |
ICD implantation | 1 (2.9) | 0 (0.0) | 0.200 |
Medications | |||
Digoxin | 2 (5.9) | 1 (0.7) | 0.041 |
β-blocker | 3 (8.8) | 7 (5.1) | 0.415 |
Calcium channel blocker | 5 (14.7) | 7 (5.1) | 0.052 |
RASi | 3 (8.8) | 6 (4.4) | 0.304 |
Antiarrhythmic drug | 2 (5.9) | 2 (1.5) | 0.129 |
Amiodarone | 1 (2.9) | 1 (0.7) | |
Flecainide | 1 (2.9) | 1 (0.7) | |
Diuretics | 3 (8.8) | 7 (5.1) | 0.415 |
Lipid lowering agent | 1 (2.9) | 2 (1.5) | 0.560 |
Antiplatelet | 1 (2.9) | 3 (2.2) | 0.800 |
Anticoagulant | 1 (2.9) | 5 (3.7) | 0.835 |
Symptoms | |||
Loss of consciousness | 3 (8.8) | 4 (2.9) | 0.144 |
Palpitations | 4 (11.8) | 3 (2.2) | 0.030 |
Chest pain | 3 (8.8) | 8 (5.9) | 0.461 |
ECG characteristics | |||
Heart rate (/min) | 52.0 (47.0–58.0) | 70.0 (62.3–84.0) | < 0.001 |
PR interval (ms) | 160.0 (146.0–175.5) | 152.0 (137.5–168.0) | 0.061 |
QT interval (ms) | 361.0 (335.0–375.5) | 380.0 (358.0–400.0) | 0.001 |
QTc (ms) | 334.0 (330.3–337.0) | 416.0 (396.3–436.8) | < 0.001 |
QT dispersion (ms) | 44.0 (28.0–73.0) | 20.0 (12.0–35.0) | < 0.001 |
JT interval (ms) | 262.0 (245.0–279.0) | 200.0 (169.0–224.0) | < 0.001 |
U wave | 4 (11.8) | 0 (0) | –a |
Biphasic T wave | 1 (2.9) | 0 (0) | –a |
Early repolarization | 25 (73.5) | 14 (10.3) | < 0.001 |
Tall T waves | 20 (58.8) | 10 (7.4) | < 0.001 |
PVC | 2 (5.8) | 2 (1.5) | 0.179 |
SVT | 2 (5.8) | 2 (1.5) | 0.179 |
Follow-up period (year) | 4.9 (2.0–7.8) | 3.8 (3.8–4.2) | 0.318 |