Table 1. Overview of studies and their main findings discussed in this review.
| Articles | Definition of the risk factor | N | Follow-up (years) Mean ± SD or median (range) | Incidence of SCD | Univariate HR (95%CI) or p value | Multivariate HR (95%CI) or p value |
|---|---|---|---|---|---|---|
| Age (1 study demonstrated statistically significant independent association*) | ||||||
| Maki et al.31 | Continuous variable (years) | 309 | 9.4 (2–25) | 28/309 | 0.99 (0.97–1.02) | No data |
| Sorajja et al.44 | Continuous variable (years) | 433 | 5.9 (0.1–25.3) | 29/433 | No data | 1.01 (0.98–1.03) |
| Kofflard et al.17 | Continuous variable (years) | 225 | 7.5 ± 7 | 20/225 | No data | NS (numerical data NA) |
| Maron MS et al.45 | <20, 20-39, 40-60, >60 years | 1101 | 6.3 ± 6.2 | 71/1101 | No data | NS (numerical data NA) |
| *Spirito et al.19 | <18, 18-39, ≥40 years | 1511 | 5.6 ± 5.2 | 74/1511 | No data | 0.63 (0.32–1.22) and 0.29 (0.15–0.57) for 18–39 and ≥40 categories, respectively |
| Sex (No study demonstrated statistically significant independent association) | ||||||
| Maki et al.31 | No definition | 309 | 9.4 (2–25) | 28/309 | 0.88 (0.10–1.65) | No data |
| Sorajja et al.44 | Female gender | 433 | 5.9 (0.1–25.3) | 29/433 | No data | 1.48 (0.68–3.21) |
| Maron MS et al.45 | Female gender | 1101 | 6.3 ± 6.2 | 71/1101 | No data | p = 0.75, other data NA |
| Olivotto et al.36 | Female gender | 969 | 6.2 ± 6.1 | 59/969 | No data | p = 0.97, other data NA |
| Non-sustained ventricular tachycardia (NSVT) on Holter (3 studies demonstrated statistically significant independent association*) | ||||||
| Maki et al.31 | HR ≥120 bpm lasting <30 seconds within 24 h | 309 | 9.4 (2–25) | 28/309 | 1.61 (0.47–2.76) | NS, numerical data NA |
| Kofflard et al.17 | Sustained or NSVT within 24 h | 225 | 7.5 ± 7 | 20/225 | No data | NS, numerical data NA |
| Elliott et al.24 | ≥ 3 beats at HR ≥120 bpm <30 seconds within 48 h | 368 | 3.6 ± 2.5 | 22/368 | 1.8 (0.7–4.7) | 1.9 (0.7–5.0) |
| *Montserrat et al.20 | ≥3 beats at HR ≥ 120 bpm <30 seconds within 24 h to 48 h | 532 | 5.8 ± 3.3 | 32/532 | No data | 2.8 (1.4–5.6) |
| *Elliott et al.32 | ≥3 beats at HR ≥ 120 bpm <30 seconds within 48 h | 917 | 5 (2.5–8.3) | 54/917 | No data | 3.84 (2.1–7.0) |
| *Gimeno et al.21 | ≥3 beats at HR ≥ 120 bpm <30 seconds within 24 h to 48 h | 1380 | 4.5 ± 4 | No data | No data | 2.57 (1.55–4.26) |
| Severe hypertrophy on echocardiography (4 studies demonstrated statistically significant independent association*) | ||||||
| Maki et al.31 | Continuous variable (septal thickness in mm) | 309 | 9.4 (2–25) | 28/309 | 1.03 (0.97–1.09) | No data |
| Kofflard et al.17 | ≥25 mm | 225 | 7.5 ± 7 | 20/225 | No data | NS (numerical data NA) |
| Maron MS et al.45 | ≥30 mm | 1101 | 6.3 ± 6.2 | 71/1101 | No data | p = 0.82 (other data NA) |
| *Spirito et al.19 | ≤10, 11-15, 16-19, 20-24, 25-29, 30-34, ≥35 mm | 1511 | 5.6 ± 5.2 | 74/1511 | No data | p = 0.04 for strata comparison |
| *Elliott et al.24 | ≥ 30mm | 368 | 3.6 ± 2.5 | 36/368 | 4.1 (1.7–9.5) | 2.9 (1.1–7.1) |
| *Montserrat et al.20 | ≥ 30 mm in patients ≤30 years old | 532 | 5.8 ± 3.3 | 32/532 | No data | 3.5 (1.2–10.7) |
| Elliott et al.32 | ≥ 30 mm | 917 | 5 (2.5–8.3) | 54/917 | No data | 1.70 (0.8–3.8) |
| Gimeno et al.21 | ≥ 30 mm | 1380 | 4.5 ± 4 | No data | No data | 0.90 (0.42–1.93) |
| *Spirito et al.25 | ≤10, 11-15, 16-19, 20-24, 25-29, 30-34, ≥35 mm | 480 | 6.5 ± 4.6 | 23 | p = 0.001 | 1.76 (1.19–2.60) |
| Abnormal blood pressure response to exercise (1 study demonstrated statistically significant independent association; different definition) | ||||||
| * Maki et al.31 | Exercise-induced change in SBP | 309 | 9.4 (2–25) | 28/309 | 0.97 (0.96–0.99) | p < 0.05 (other data NA) |
| Elliott et al.24 | Failure to ↑ SBP 25 mmHg from baseline to peak exercise or ↓ 15 mmHg during exercise & ≤40 years old | 368 | 3.6 ± 2.5 | 36/368 | 2.4 (1.0–5.5) | 1.8 (0.7 to 4.4) |
| Montserrat et al.20 | SBP failed to ↑ >25 mmHg from baseline, or ↓ >10 mmHg from maximum BP during exercise & ≤30 years old | 532 | 5.8 ± 3.3 | 32/532 | No data | 0.5 (0.2–1.7) |
| Elliott et al.32 | SBP failed to ↑ >25 mmHg from baseline, or ↓ >10 mmHg from maximum BP during exercise & ≤40 years old | 917 | 5 (2.5–8.3) | 54/917 | No data | 1.42 (0.7–2.8) |
| Gimeno et al.21 | SBP failed to ↑ >25 mmHg from baseline, or when ↓ >10 mmHg from maximum BP during exercise & ≤40 years old | 1380 | 4.5 ± 4 | No data | No data | 1.43 (0.86–2.36) |
| Family history of SCD (FH-SCD) (2 studies demonstrated statistically significant independent association*) | ||||||
| Maki et al.31 | FH-SCD judged to be probably due to HCM | 309 | 9.4 (2–25) | 28/309 | 2.44 (1.62–3.26) | NS (numerical data NA) |
| Kofflard et al.17 | FH-SCD in a first degree relative at age <40 years old | 225 | 7.5 ± 7 | 20/225 | No data | NS (numerical data NA) |
| Elliott et al.24 | FH-SCD in ≥ 2 first-degree relatives <40 years old | 368 | 3.6 ± 2.5 | 36/368 | 1.9 (0.8–4.5) | 5.3 (1.9–14.9) for FHSD and syncope |
| Montserrat et al.20 | FH-SCD in ≥ 2 first-degree relatives in patients ≤ 30 years old | 532 | 5.8 ± 3.3 | 32/531 | No data | 1.4 (0.5–4.5) |
| *Elliott et al.32 | FH-SCD in relatives <40 years old | 917 | 5 (2.5–8.3) | 54/917 | No data | 1.88 (1.0–3.5) |
| *Gimeno et al.21 | FH-SCD in relatives <40 years old | 1380 | 4.5 ± 4 | No data | No data | 1.79 (1.09–2.94) |
| Spirito et al.25 | FH-SCD ≥1 member with HCM or if one or more close relatives without documented HCM died suddenly at <50 years of age | 480 | 6.5 ± 4.6 | 23 | 2.1 (0.0–11.9) | No data |
| Unexplained syncope (4 studies demonstrated statistically significant independent association*) | ||||||
| Maki et al.31 | No definition | 309 | 9.4 (2–25) | 28/309 | 2.20 (1.30–3.11) | NS, numerical data NA |
| *Kofflard et al.17 | No definition | 225 | 7.5 ± 7 | 20/225 | No data | 4.3 (1.8–5.9) |
| *Spirito et al.19 | Syncope within previous 6 months | 1511 | 5.6 ± 5.2 | 74/1511 | No data | 4.89 (2.19–10.94) |
| Elliott et al.24 | ≥ 1 episodes of syncope within 12 previous months | 368 | 3.6 ± 2.5 | 36/368 | 2.0 (0.8 to 4.9) | 5.3 (1.9 to 14.9) for FH-SCD and syncope |
| Montserrat et al.20 | Syncope within previous 12 months in individuals ≤ 30 years old | 532 | 5.8 ± 3.3 | 32/531 | No data | 1.3 (0.4–4.3) |
| *Elliott et al.32 | Recurrent unexplained syncope within previous 12 months | 917 | 5 (2.5–8.3) | 54/917 | No data | 2.27 (1.2–4.2) |
| *Gimeno et al.21 | No definition | 1380 | 4.5 ± 4 | No data | No data | 2.08 (1.21–3.56) |
| Left ventricular outflow tract obstruction (Measured by Echo-Doppler, except in one study. 5 studies demonstrated statistically significant independent association*) | ||||||
| *Maki et al.31 | Invasive measurement ≥ 30 mmHg at rest | 309 | 9.4 (2–25) | 28/309 | 1.01 (1.01–1.02) | p < 0.05 (numerical data NA) |
| Kofflard et al.17 | ≥50 mmHg at basal conditions | 225 | 7.5 ± 7 | 20/225 | No data | NS (numerical data NA) |
| *Maron MS et al.45 | ≥ 30 mmHg at rest | 1101 | 6.3 ± 6.2 | 71/1101 | 2.1 (1.1–3.7) | 1.9 (1.1–3.5) |
| *Olivotto et al.36 | ≥30 mmHg at rest | 969 | 6.2 ± 6.1 | 59/969 | No data | 1.84 (1.14–2.98) |
| *Elliott et al.32 | ≥90 mmHg | 917 | 5 (2.5–8.3) | 54/917 | No data | 3.82 (1.6–9.2) |
| *Gimeno et al.21 | ≥90 mmHg | 1380 | 4.5 ± 4 | No data | No data | 2.41 (1.08–5.53) |
| Spirito et al.25 | ≥30 mmHg at basal conditions | 480 | 6.5 ± 4.6 | 23 | NS, p = 0.63 (comparison of incidences) | NS, p = 0.76 (comparison of incidences) |
| Atrial fibrillation (AF) (1 study demonstrated statistically significant independent association*) | ||||||
| Maki et al.31 | No definition | 309 | 9.4 (2–25) | 28/309 | 0.4997 (−0.939–1.938) | No data |
| *Sorajja et al.44 | Chronic AF | 433 | 5.9 (0.1–25.3) | 29/433 | No data | 4.90 (1.49–16.67) |
| Kofflard et al.17 | Persistent AF | 225 | 7.5 ± 7 | 20/225 | No data | NS (numerical data NA) |
| Maron MS et al.45 | Paroxysmal or chronic AF | 1101 | 6.3 ± 6.2 | 71/1101 | No data | NS, p = 0.72 (other data NA) |
| Left atrial size on echocardiography (1 study demonstrated statistically significant independent association*) | ||||||
| Maki et al.31 | Continuous variable (mm) | 309 | 9.4 (2–25) | 28/309 | 1.06 (1.00–1.12) | No data |
| Spirito et al.25 | <40 mm, 40–50 mm, >50 mm | 480 | 6.5 ± 4.6 | 23/480 | NS, p = 0.30 (comparison of incidences) | NS, p = 0.21 (other data NA) |
| *Spirito et al.19 | Continuous variable (mm) | 1511 | 5.6 ± 5.2 | 74/1511 | No data | 1.03 (1.00–1.06) |
Notes.
Abbreviations
- SD
- Standard deviation
- NS
- Non-significant
- NA
- Not available
- HR
- Heart rate
- SBP
- Systolic blood pressure
- BPM
- Beats per minute