Table 1.
Characteristics of the case reports.
| References | Country | Study design | Patient (n) | Age (y, mean ±SD) | Female (n, %) | High risk factors (n, %) | Structural heart disease (n, %) | Family history of cardiac disease or sudden death (n, %) | Emotion and exercise (n, %) | Syncope (n, %) | Sudden cardiac arrest (n, %) | Exercise testing (-) (n, %) | Provocative testing (-) (n, %) | Genetic testing | QT interval | First coupling interval (ms, mean ±SD) | Programmed stimulation (+) (n, %) | QRS duration of ventricular extrasystole (ms, mean ± SD) | ICD (n, %) | Arrhythmia recurrence (n, %) | Follow-up (months, mean ±SD) | Alive (n, %) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Leenhardt (2) | France | Case report | 21 | 33 ± 11 | 10 (48) | 1 (5) | 0 (0) | 5 (24) | 3 (18) | 20 (95) | 1 (5) | 9 (64) | 12 (86) | NA | Normal | 297 ± 41 | 2 (14) | NA | 4 (19) | 9 (43) | 52 ± 51 | 15 (71) |
| Ruan and Wang (9) | China | Case report | 3 | 36 ± 5 | 2 (67) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 3 (100) | 0 (0) | NA | 2 (67) | NA | Normal | 377 ± 25 | NA | NA | 0 (0) | 1 (33) | 7 ± 6 | 2 (67) |
| Shiga et al. (11) | Japan | Case report | 1 | 41 | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 1 (100) | 0 (0) | NA | 0 (0) | NA | Normal | 240 | 1 (100) | 156 | 1 (100) | 1 (100) | 60 | 1 (100) |
| Haïssaguerre et al. (10) | France, Japan, Czech Republic, UK and Brazil |
Case report | 27 | 41 ± 14 | 14 (52) | 0 (0) | 0 (0) | 6 (22) | 0 (0) | 17 (63) | 0 (0) | 27 (100) | 27 (100) | NA | Normal | 297 ± 41 | 10 (37) | 129 ± 18 | 23 (85) | 3 (11) | 24 ± 28 | 27 (100) |
| Takeuchi et al. (14) | Japan | Case report | 1 | 51 | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 1 (100) | 0 (0) | NA | 1 (100) | NA | Normal | 280 | 0 (0) | 120 | 1 (100) | 0 (0) | 6 | 1 (100) |
| Noda et al. (8) | Japan | Case control study | 16 | 39 ± 10 | 9 (56) | 0 (0) | 0 (0) | 1 (6) | 0 (0) | 11 (69) | 0 (0) | 16 (100) | 16 (100) | NA | Normal | 403 ± 21 | 3 (19) | 148 ± 8 | 1 (6) | 0 (0) | 54 ± 39 | 16 (100) |
| Viskin et al. (19) | Israel | Case report | 3 | 48 ± 11 | 3 (100) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 1 (33) | 0 (0) | 3 (100) | 3 (100) | NA | Normal | 350 ± 20 | 0 (0) | 149 ± 7 | 2 (67) | 0 (0) | 42 ± 48 | 3 (100) |
| Yamazaki et al. (20) | Japan | Case report | 1 | 21 | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 1 (100) | 1 (100) | NA | Normal | 300 | 0 (0) | 120 | 0 (0) | 0 (0) | 36 | 1 (100) |
| Bogaard et al. (16) | Netherlands | Case report | 1 | 36 | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 1 (100) | 0 (0) | NA | 1 (100) | NA | Normal | 240 | 0 (0) | 120 | 1 (100) | 0 (0) | 6 | 1 (100) |
| Chiladakis et al. (3) | Greece | Case report | 1 | 50 | 1 (100) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 1 (100) | 0 (0) | NA | 1 (100) | NA | Normal | 290 | 0 (0) | 120 | 1 (100) | 0 (0) | 3 | 1 (100) |
| Van den branden et al. (12) | Netherlands | Case report | 1 | 51 | 0 (0) | 1 (100) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 1 (100) | 1 (100) | NA | NA | Normal | 240 | NA | 160 | 1 (100) | 0 (0) | 12 | 1 (100) |
| Chokr et al. (6) |
Brazil | Case report | 4 | 32 ± 16 | 4 (100) | 0 (0) | 0 (0) | 0 (0) | 3 (75) | 3 (75) | 0 (0) | 2 (50) | 2 (50) | NA | Normal | 300 ± 43 | 0 (0) | 155 ± 13 | 3 (75) | 1 (25) | 71 ± 90 | 4 (100) |
| Hayama et al. (15) | Japan | Case report | 1 | 38 | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 1 (100) | 0 (0) | NA | 1 (100) | (-) | Normal | 280 | 0 (0) | 142 | 1 (100) | 0 (0) | 15 | 1 (100) |
| Jastrzebski et al. (5) | Kraków | Case report | 5 | 43 ± 19 | 4 (80) | 1 (20) | 1 (20) | 0 (0) | 0 (0) | 5 (100) | 0 (0) | 1 (20) | NA | NA | Normal | 303 ± 38 | NA | 130 ± 17 | 5 (100) | 3 (60) | 51 ± 29 | 5 (100) |
| Kondo et al. (23) | Japan | Case report | 1 | 19 | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 1 (100) | 0 (0) | NA | 1 (100) | (-) | Normal | 300 | 0 (0) | 128 | 1 (100) | 0 (0) | 8 | 1 (100) |
| Godinho et al. (13) | Portugal | Case report | 1 | 49 | 1 (100) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 1 (100) | 0 (0) | NA | 1 (100) | NA | Normal | 280 | 0 (0) | 160 | 1 (100) | 0 (0) | 6 | 1 (100) |
| Fujii et al. (17) | Japan | Case report | 6 | 38 ± 9 | 3 (50) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 6 (100) | 0 (0) | 1 (17) | 3 (50) | (+) | Normal | 426 ± 21 | 3 (50) | 138 ± 16 | 6 (100) | 3 (50) | 62 ± 25 | 6 (100) |
| Kimura et al. (18) | Japan | Case report | 1 | 40 | 1 (100) | 0 (0) | 0 (0) | 1 (100) | 0 (0) | 1 (100) | 0 (0) | 0 (0) | 1 (100) | (+) | Normal | 280 | 0 (0) | 110 | 1 (100) | 0 (0) | NA | 1 (100) |
| Kajiyama et al. (24) | Japan | Case report | 1 | 40 | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 1 (100) | 0 (0) | NA | 1 (100) | (+) | Normal | 250 | 0 (0) | 130 | 1 (100) | 1 (100) | 24 | 1 (100) |
| Sonoda et al. (22) | Japan | Case report | 1 | 38 | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 0 (0) | 1 (100) | 0 (0) | NA | 1 (100) | (+) | Normal | 280 | 0 (0) | 120 | 1 (100) | 0 (0) | NA | 1 (100) |
| Steinfurt et al. (21) | Germany, USA and Netherlands | Case report | 5 | 37 ± 13 | 2 (40) | 0 (0) | 0 (0) | 1 (20) | 0 (0) | 1 (20) | 4 (80) | NA | 5 (100) | NA | Normal | 262 ± 20 | 0 (0) | 126 ± 5 | 5 (100) | 0 (0) | 32 ± 37 | 5 (100) |
| Touat-Hamici et al. (7) | France | Case report | 1 | 35 | 0 (0) | 0 (0) | 0 (0) | 1 (100) | 0 (0) | 1 (100) | 0 (0) | 1 (100) | NA | (+) | Normal | 280 | NA | 120 | 0 (0) | 1 (100) | 72 | 0 (0) |
| Total | - | - | 103 | 38 ± 12 | 54 (52) | 3 (3) | 1 (1) | 15 (15) | 6 (6) | 78 (76) | 6 (6) | 62 (78) | 80 (91) | – | Normal | 302 ± 62 | 19 (22) | 135 ± 17 | 60 (58) | 23 (22) | 40 ± 41 | 95 (92) |
ICD, Implantable cardioverter defibrillator; SD, Standard deviation; NA, Not applicable.