Characteristics |
Black (10–18 years) |
Caucasian (8–18 years) | % Difference |
PR interval (ms) | 161 (146–177) (2; 196) (91.6%) | 141 (135–148) (3; 2529) (95%) | 12 |
QRS duration (ms) | 86 (82–90)
†
(3; 525) (94.9%) | 92 (88–95) (4; 3232) (98.3%) | −7 |
QTc duration (ms) | 394 (387–401) (3; 525) (95%) | 398 (392–403) (4; 3232) (98.4%) | −1 |
Group 1 ECG patterns | Odds ratio | ||
Sinus bradycardia (%) | 38.2 (18.6–60.1)‡ (3; 525) (95%) | 29.3 (10.9–52.2) (5; 6197) (99%) | 1.5 (1.3–1.8) |
First-degree AV block (%) | 11.4 (6.9–16.9)‡ (2; 483) (65%) | 1.1 (0.25–2.5) (4; 5991) (92%) | 11.6 (8.0–17.0) |
Incomplete RBBB (%) | 22.1 (13.1–32.7) (3; 525) (83%) | 21.1 (15.0–27.9) (5; 6197) (97%) | 1.1 (0.9–1.3) |
LVH (%) | 60.3 (11.0–98.3)‡ (3; 525) (99%) | 28.1 (20.2–36.7) (5; 6197) (97%) | 3.9 (3.3–4.7) |
ER (%) | 74.3 (41.0–96.6)‡ (3; 525) (98%) | 31.0 (17.4–46.5) (5; 6197) (99%) | 6.4 (5.2–7.9) |
Group 2 ECG patterns | Risk ratio | ||
TWI (≥1 mm) (%) | 23.4 (19.8–27.1)‡ (3; 512) (69%) | 5.9 (5.3–6.6) (5; 5263) (71%) | 4.0 (3.3–4.8) |
Deep TWI (≥2 mm) (%) | 10.6 (5.5–17.2)‡ (3; 525) (73%) | 4.2 (0.7–10.4) (4; 3936) (97%) | 2.6 (1.9–3.4) |
Anterior (%) | 12.2 (8.2–16.9)‡ (3; 512) (43%) | 4.2 (3.0–5.6) (4; 6063) (25%) | 2.9 (2.2–3.8) |
Anterior extended (%) | 10.8 (7.8–14.2)‡ (2; 358) (0%) | 0.3 (0.03–0.8) (3; 3298) (66%) | 36 (18 – 71) |
Inferolateral (%) | 8.2 (6.0–10.7)‡ (3; 512) (95%) | 1.3 (0.3–3.1) (4; 6063) (0%) | 6.5 (4.5–9.3) |
Abnormal Q waves (%) | 0.5 (0.0–2.0)* (3; 526) (52%) | 0.1 (0.04–0.3) (4; 6135) (19%) | 5.0 (1.3–19.3) |
LAE (%) | 5.7 (1.2–1.3)‡ (4; 680) (91%) | 2.0 (0.02–7.0) (4; 3936) (97%) | 2.9 (2.0–4.2) |
LAD (%) | 0.8 (0.0–3.1) (2; 484) (70%) | 0.7 (0.4–0.9) (2; 3668) (0%) | 1.3 (0.4–3.6) |
Complete RBBB (%) | 0.3 (0.02–1.1) (2; 483) (0%) | 0.3 (0.2–0.6) (4; 5991) (46%) | 1.2 (0.3–5.0) |
Long QT (%) | 1.1 (0.03–3.7) (3; 638) (79%) | 0.1 (0.0–0.2) (4; 5991) (0%) | 16.4 (4.8–56.0) |
Data are presented as mean or percentage (95% CI) (number of articles; number of participants) (heterogeneity).
*p≤0.05, significantly greater or more prevalent in black than Caucasian athletes.
†p≤0.01, significantly greater or more prevalent in black than Caucasian athletes.
‡p≤0.001, significantly greater or more prevalent in black than Caucasian athletes.
Anterior, V1–V3; extended anterior, V1–V4; inferolateral, leads II-aVF/V4-V6/I-aVL; LAE, left atrial enlargement; LAD, left axis deviation; LVH, left ventricular hypertrophy; RBBB, right bundle branch block; TWI, T-wave inversion.