Table 1.
Clinical characteristics of studied patients
| Genotype-negative | LQT1 | LQT2 | LQT3 | p-value 1–2-3 | |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | ||
| # of Patients | 2043 | 784 | 746 | 233 | |
| Probands, n(%) | N/A | 136 (17) | 166 (22) | 35 (15) | 0.012 |
| Male, n (% ) | 938(46) | 330(42) | 329(44) | 102(44) | 0.715 |
| Age at enrolment, years | 23±21 | 26±21* | 25±21* | 26±20 | 0.862 |
| Atrial Fibrillation | |||||
| AF at any time, n (%) | 29(1.4) | 16(2.0) | 3(0.4)* | 17(7.3) | <0.001 |
| AF in probands, n (%) | N/A | 4 (2.9) | 2 (1.2) | 4 (11) | 0.005 |
| Age at1st AFib, yr | 71±11 | 58±17* | 46±16* | 49±21* | 0.393 |
| AF<=60 years, n (%) | 6(0.3) | 6(0.8) | 2(0.3) | 12(5.2)† | <0.001 |
| AF> 60 years, n (%) | 19 (1.1) | 11 (1.4) | 1 (0.1)* | 6 (2.5) | 0.003 |
| ECG, mean±sd | |||||
| RR, sec | 772±218 | 831±216† | 823±245† | 836±245† | 0.702 |
| PR, sec | 147±30 | 152±33† | 148±29 | 157±32† | <0.001 |
| QTc, msec | 422±31 | 480±48† | 480±54† | 478±53† | 0.740 |
| Treatment, n (%) | |||||
| Beta-blockers | 311(15) | 543(69) † | 582(78) † | 142(61) † | <0.001 |
| Class I and III AAD | 20 (1.0) | 13 (1.6) | 7 (0.9) | 38 (16) † | <0.001 |
| LCSD | 0(0) | 8(1) † | 14(2) † | 2(1)* | 0.315 |
| Pacemaker | 25(1) | 33(4) † | 78(10) † | 17(7) † | <0.001 |
| ICD | 12(1) | 105(13) † | 194(26) † | 80(34) † | <0.001 |
| Cardiac Events During Follow Up, n(%) | |||||
| Syncope | 269(13) | 309(39) † | 312(42) † | 64(27) † | <0.001 |
| ACA | 9(0) | 29(4) † | 57(8) † | 18(8) † | 0.002 |
| Sudden Cardiac Death | 0(0) | 13(2) † | 19(3) † | 12(5) † | 0.011 |
| Appropriate Shock | 0(0) | 18(2) † | 37(5) † | 8(3) † | 0.019 |
AAD - antiarrhythmic drugs; ACA – aborted cardiac arrest; AF – atrial fibrillation; ICD – implantable cardioverter-defibrillator; LCSD – left cardiac sympathetic denervation
*
- p<0.05 in comparison with Genotype-negative group
†
- p<0.001 in comparison with Genotype-negative group