Table 1

Clinical characteristics

No events in 5 yearsDeath in 5 yearsICD shock in 5 yearsP value
N1492294162
Female sex319 (21.4%)45 (15.3%)17 (10.5%)0.002
Ischaemic HD883 (59.2%)202 (68.7%)142 (87.7%)0.003
Non-ischaemic HD595 (39.9%)86 (29.3%)49 (30.2%)0.007
CRT-D device implanted589 (39.5%)159 (54.1%)73 (45.1%)<0.001
Age (years)64.0 (55.0–71.2)69.3 (62.5–74.8)63.8 (55.2–70.4)<0.001
Heart rate (bpm)69.0 (59.9–79.4)72.9 (65.1–83.9)68.0 (58.3–77.5)<0.001
LVEF (%)26 (21–31)25 (20–30)25 (20–31)<0.001
QRS (ms)127 (112–159)146 (122–171)131 (114–158)<0.001
QRS-T angle (o)151.3 (117.0–165.2)159.9 (142.8–167.4)148.3 (109.3–162.1)<0.001
QRS n-pl (8 leads) (%)4.49 (3.06–6.88)5.59 (3.55–8.20)5.21 (3.76–7.05)<0.001
T wave n-pl (8 leads) (%)2.87 (1.90–4.51)3.06 (2.00–4.66)3.55 (2.36–5.67)<0.001
QRS n-pl (3 leads) (%)4.34 (2.83–6.77)6.00 (3.65–9.08)4.55 (2.90–6.87)<0.001
T wave n-pl (3 leads) (%)3.03 (1.85–4.94)3.32 (1.95–5.76)3.85 (2.29–6.08)0.001
QTc interval (ms)442.2 (418.6–467.2)452.4 (428.3–484.8)442.1 (421.7–467.1)<0.001
TpTe interval (ms)97 (85–113)98 (84–115)96.5 (86–109)0.928
  • The characteristics are shown for population subgroups stratified according to the events during 5-year follow-up (patients who experienced ICD shocks and subsequently died are included among those who died). Note that in 21 patients, the distinction between ischaemic and non-ischaemic HD was unclassified. The values shown are total count (percentage) for categorical variables, and median value (IQR) for continuous variables. The p values show χ2 (for categorical variables) and Kruskal-Wallis (for continuous variables) comparisons of the distribution of the three study subgroups.

  • bpm, beats per minute; CRT-D, cardiac resynchronisation therapy-defibrillator; HD, heart disease; ICD, implantable cardioverter-defibrillator; LVEF, left ventricular ejection fraction; n-pl, non-planarity of the three-dimensional loop; TpTe, T-peak to T-end.