Table 6. Comparisons between derivation and validation cohorts.
| Peak CPET | Anaerobic threshold | |||||
|---|---|---|---|---|---|---|
|
|
|
|||||
| Variable | Derivation cohort (n = 136) | Validation cohort (n = 30) | p value | Derivation cohort (n = 246) | Validation cohort (n = 69) | p value |
| Patient characteristics | ||||||
| Height (cm) | 155.3 ± 13.1 | 151.1 ± 15.5 | 0.13 | 149.7 ± 14.5 | 151.3 ± 15.7 | 0.64 |
| Weight (kg) | 49.3 ± 15.9 | 44.2 ± 13.9 | 0.11 | 45.0 ± 15.8 | 44.6 ± 16.6 | 0.6 |
| Age at exercise (years) | 13.9 ± 2.9 | 13.9 ± 2.9 | 0.92 | 12.9 ± 3.0 | 13.1 ± 3.3 | 0.24 |
| Age at Fontan (years) | 3.7 ± 2.3 | 2.7 ± 1.2 | 0.04 | 3.5 ± 2.2 | 3.3 ± 2.0 | 0.44 |
| Male, n (%) | 78 (57) | 16 (53) | 0.69 | 141 (57) | 49 (71) | 0.04 |
| d-looped ventricles, n (%) | 104 (77) | 20 (67) | 0.23 | 190 (77) | 59 (86) | 0.14 |
| Right dominant ventricle, n (%) | 44 (32) | 8 (17) | 0.09 | 81 (33) | 18 (26) | 0.28 |
| Sinus rhythm at rest, n (%) | 98 (72) | 18 (60) | 0.19 | 164 (67) | 52 (75) | 0.17 |
| Fenestration present, n (%) | 14 (10) | 1 (3) | 0.22 | 22 (9) | 7 (10) | 0.78 |
| CPET variables | ||||||
| Peak VO2 (L/min) | 1.31 ± 0.46 | 1.17 ± 0.44 | 0.13 | |||
| Maximum work (W) | 99.6 ± 38 | 93.5 ± 34 | 0.42 | |||
| Maximum O2 pulse (mL 02/min) | 8.35 ± 2.98 | 7.52 ± 2.63 | 0.16 | |||
| VO2 at AT (L/min) | 0.82 ± 0.50 | 0.83 ± 0.34 | 0.83 | |||
| Work at AT | 48.9 ± 24.0 | 55.0 ± 26.7 | 0.64 | |||
| 02 pulse at AT | 6.23 ± 3.4 | 6.56 ± 3.7 | 0.63 | |||
| VE/VCO2 at AT | 42.8 ± 3.9 | 44.5 ± 12.3 | 0.03 | |||
| VE/VO2 at AT | 41.5 ± 9.6 | 43.0 ± 11.3 | 0.19 | |||