Table 1.
Baseline Characteristics
| Characteristics | Total Cohort (n=276) | ICD‐per‐Guideline (n=228) | ICD‐Off‐Label (n=48) | P Value |
|---|---|---|---|---|
| Age, y | 67±10 | 67±10 | 65±10 | 0.19 |
| Male sex, n (%) | 242 (80) | 197 (86) | 45 (94) | 0.16 |
| Cardiovascular risk factors | ||||
| Diabetes mellitus, n (%) | 56 (20) | 51 (22) | 5 (10) | 0.06 |
| Hypertension, n (%) | 120 (44) | 98 (52) | 22 (51) | 0.91 |
| Hyperlipidemia, n (%) | 82 (30) | 69 (38) | 13 (32) | 0.43 |
| BMI, kg/m2 | 27±4 | 27±4 | 27±4 | 0.46 |
| Medical history | ||||
| Prior MI, n (%) | 180 (65) | 159 (70) | 21 (44) | <0.01 |
| Prior PCI, n (%) | 90 (33) | 78 (34) | 12 (25) | 0.22 |
| Prior CABG, n (%) | 61 (22) | 58 (25) | 3 (6) | <0.01 |
| LVEF, %* | 38±11 | 36±11 | 48±8 | <0.01 |
| Atrial fibrillation, n (%) | 89 (32) | 79 (35) | 10 (21) | 0.06 |
| Creatinine, µmol/L, median (IQR) | 86 (76–102) | 88 (77–103) | 83 (71–95) | 0.08§ |
| QRS duration, ms, median (IQR) | 108 (96–126) | 110 (96–128) | 98 (91–114) | <0.01§ |
| Cardiac findings and intervention at index event | ||||
| VF at time of OHCA, n (%) | 180 (65) | 143 (63) | 37 (77) | 0.06 |
| CK‐MB†, µg/L | 22 (8–45) | 22 (8–56) | 25 (8–40) | 0.98§ |
| Troponin T‡, µg/L, median (IQR) | 0.33 (0.11–0.98) | 0.32 (0.11–0.95) | 0.37 (0.13–1.00) | 0.72§ |
| Moderate/extensive exercise before arrest, n (%) | 69 (25) | 52 (24) | 17 (36) | 0.08 |
| Diffuse nonobstructive CAD, n (%) | 74 (26) | 73 (32) | 1 (2) | <0.01 |
| Multivessel disease, n (%) | 163 (59) | 133 (58) | 30 (63) | 0.59 |
| CTO present (no prior CABG), n (%) | 100 (36) | 90 (40) | 10 (21) | 0.02 |
| PCI performed, n (%) | 102 (37) | 67 (29) | 35 (73) | <0.001 |
| CABG performed, n (%) | 26 (9) | 12 (5) | 14 (29) | <0.001 |
| Complete revascularization, n (%) | 143 (52) | 95 (42) | 48 (100) | <0.001 |
| Medication at time of ICD implantation | ||||
| ACEi/ARB, n (%) | 237 (86) | 194 (85) | 43 (90) | 0.42 |
| Beta‐blockers, n (%) | 251 (91) | 205 (90) | 46 (96) | 0.27 |
| Calcium channel blocker, n (%) | 23 (8) | 20 (9) | 3 (6) | 0.78 |
| Amiodarone, n (%) | 39 (14) | 35 (15) | 4 (8) | 0.21 |
| Device type | ||||
| ICD, n (%) | 259 (94) | 211 (93) | 48 (100) | 0.50 |
| CRT‐D, n (%) | 17 (6) | 17 (8) | 0 | 0.50 |
Dichotomous variables compared using the chi‐square test or Fischer's exact test. Continuous variables compared using t‐tests unless otherwise indicated. *Based on 199 patients; †Based on N=151; ‡Based on N=156; §Tested using Mann–Whitney U test. ACEi indicates angiotensin‐converting enzyme inhibitors; ARB, angiotensin receptor blocker; BMI, body mass index; CABG, coronary arterial bypass graft surgery; CAD, coronary artery disease; CK‐MB, creatine kinase myocardial band; CRT‐D, resynchronisation therapy defibrillator; CTO, coronary chronic total occlusion; ICD, implantable cardioverter defibrillator; IQR, interquartile region; MI, myocardial infarction; OHCA, out‐of‐hospital cardiac arrest; PCI, percutaneous coronary intervention; and VF, ventricular fibrillation.