Table 2.
All (n = 348) | SP ON (n = 316) | SP OFF (n = 32) | P | |
---|---|---|---|---|
Age | 47.0 (35.0–55.0) | 53.0 (37.0–59.5) | 46.0 (35.0–54.0) | 0.079 |
Male | 239 (68.7%) | 221 (69.9%) | 18 (56.2%) | 0.11 |
Previous atrial fibrillation | 12 (3.4%) | 10 (3.2%) | 2 (6.2%) | 0.36 |
Hypertrophic cardiomyopathy | 108 (31.0%) | 102 (32.3%) | 6 (18.8%) | 0.11 |
Ischaemic heart disease | 67 (19.3%) | 60 (19.0%) | 7 (21.9%) | 0.69 |
Dilated cardiomyopathy | 56 (16.1%) | 52 (16.5%) | 4 (12.5%) | 0.56 |
Arrhythmogenic cardiomyopathy | 28 (8.0%) | 21 (6.6%) | 7 (21.9%) | <0.005 |
Left ventricular ejection fraction <35% | 83 (27.5%) | 75 (27.6%) | 8 (26.7%) | 0.92 |
Secondary prevention | 98 (28.2%) | 90 (28.5%) | 8 (25.0%) | 0.68 |
S-ECG x2 gain | 15 (4.3%) | 8 (2.5%) | 7 (21.9%) | ≤ 0.0001 |
Primary vector | 178 (51.1%) | 164 (51.9%) | 14 (43.8%) | 0.38 |
Secondary vector | 128 (36.8%) | 117 (37.0%) | 11 (34.4%) | 0.77 |
Alternate vector | 42 (12.1%) | 35 (11.1%) | 7 (21.9%) | 0.074 |
QRS (ms) | 96 (86–100) | 98 (90–104) | 95 (85–100) | 0.16 |
Conditional zone (b.p.m.) | 200 (200–220) | 200 (200–220) | 200 (200–220) | 0.75 |
Non-conditional zone (b.p.m.) | 70 (61–81) | 87 (70–98) | 68 (59–81) | 0.4 |
DFT shock impedance (ohms) | 250 (230–250) | 250 (230–250) | 250 (230–250) | <0.001 |
Appropriate therapy | 15 (4.3%) | 13 (4.1%) | 2 (6.2%) | 0.57 |
Inappropriate therapy | 27 (7.8%) | 16 (5.1%) | 11 (34.4%) | ≤ 0.0001 |