Clinical characteristics at the time of implantable cardioverter-defibrillator implantation
| Whole group | PP | SP | p Value* | |
|---|---|---|---|---|
| ABPR, abnormal blood pressure response; ASH, asymmetric septal hypertrophy; FHxSCD, family history of sudden cardiac death; FS, fractional shortening; ICD, implantable cardioverter-defibrillator; LAD, left atrium diameter; LVEDD, left ventricular end-diastolic dimension; LVESD, left ventricular end-systolic dimension; LVH, left ventricular hypertrophy; LVOTO, left ventricular outflow tract obstruction; MLVWT, maximum left ventricular wall thickness; NSVT, non-sustained ventricular tachycardia; NYHA, New York Heart Association; PP, primary prevention; SP, secondary prevention; VF, ventricular fibrillation; VT, ventricular tachycardia. | ||||
| Values are n (%) or median (range). | ||||
| *PP vs SP. | ||||
| †In the PP group, all patients had ⩾2 risk factors; 5 (29.4%) patients had 3 risk factors and 2 (11.8%) had 4. | ||||
| ‡6 patients were receiving >1 drug (amiodarone with β-blockers, n = 2; β-blockers with disopyramide, n = 2; β-blockers with calcium antagonists, n = 1; and disopyramide with calcium antagonists, n = 1). | ||||
| Demographics | ||||
| Male | 13 (59.1) | 8 (47.1) | 5 (100) | 0.05 |
| Female | 9 (40.9) | 9 (52.9) | 0 | |
| Age at time of ICD implantation (years) | 14 (7–16) | 14 (12–16) | 13 (7–16) | 0.21 |
| Age at diagnosis (years) | 8 (0.3–16) | 7 (0.3–15) | 13 (2–16) | 0.14 |
| Symptoms and risk factors† | ||||
| Asymptomatic | 4 (18.2) | 2 (11.8) | 2 (40) | 0.21 |
| Palpitation | 9 (40.9) | 9 (52.9) | 0 | 0.05 |
| NYHA dyspnoea class | ||||
| I | 11 (50) | 6 (35.3) | 5 (100) | |
| II | 8 (36.4) | 8 (47.1) | 0 | 0.04 |
| III/IV | 3 (13.6) | 3 (17.6) | 0 | |
| Chest pain | 12 (54.5) | 11 (64.7) | 1 (20) | 0.14 |
| Presyncope | 10 (45.5) | 8 (47.1) | 2 (40) | 1 |
| Syncope | 7 (31.8) | 6 (35.3) | 1 (20) | 1 |
| ABPR | 15 (75) | 13 (81.3) | 2 (50) | 0.25 |
| FHxSCD | 12 (54.5) | 12 (70.6) | 0 | 0.01 |
| NSVT | 1 (4.5) | 1 (5.9) | 0 | 1.0 |
| Severe LVH | 11 (50) | 10 (58.8) | 1 (20) | 0.31 |
| VF/polymorphic VT | 5 (22.7) | 0 | 5 (100) | NA |
| Drugs‡ | 16 (72.7) | 14 (82.4) | 2 (40) | 0.1 |
| Amiodarone | 3 | 2 | 1 | |
| β-Blockers | 9 | 8 | 1 | |
| Calcium antagonist | 5 | 5 | 0 | |
| Disopyramide | 3 | 3 | 0 | |
| Echocardiographic data | ||||
| MLVWT (mm) | 29.5 (12–47) | 31 (16–47) | 20 (12–34) | 0.12 |
| Distribution | ||||
| ASH | 21 (95.5) | 17 (100) | 4 (80) | |
| Concentric | 1 (4.5) | 0 | 1 (20) | 0.23 |
| LVEDD (mm) | 39.5 (26–51) | 39 (30–51) | 42 (26–49) | 0.98 |
| LVESD (mm) | 23 (10–34) | 23 (10–34) | 24 (15–30) | 0.51 |
| FS (%) | 42 (31–67) | 43 (31–67) | 41 (33–45) | 0.29 |
| LAD (mm) | 39.5 (29–56) | 40 (29–56) | 36 (29–43) | 0.56 |
| LVOTO ⩾30 mm Hg | 8 (36.4) | 7 (41.2) | 1 (20) | 0.61 |