Table 1

Baseline characteristics of the study population

Demographic characteristicsFontan subjects
(n=10)
Controls
(n=10)
P value
Age (years)24.5 (20.8–34.0)30.5 (27.5–43.3)0.075
Male sex5 (50)5 (50)>0.999
BMI (kg/m2)23.0 (21.0–27.0)22.0 (20.8–25.0)0.761
Age at Fontan procedure (years)2.0 (2.0–7.5)
Indexed CMR flows (L/min/m2)
SVC0.72 (0.55–0.93)1.05 (0.97–1.15) 0.006
Fontan/Sup-IVC1.75 (1.67–2.07)2.10 (1.97–2.38) 0.031
Sub-IVC0.99 (0.80–1.37)1.33 (1.17–1.47) 0.049
HV0.81 (0.62–1.03)0.79 (0.74–1.03)0.734
PoV0.51 (0.37–0.60)0.59 (0.51–0.78)0.104
PBF2.48 (2.33–2.99)3.37 (3.09–3.81) 0.007
CO2.88 (2.28–3.35)2.97 (2.76–3.42)0.345
Cardiopulmonary function tests*
Resting oxygen saturation (%)98 (90–99)
Spirometry
 FEV1 (absolute, L)2.99 (2.01–3.49)
 FEV1 (% predicted)71 (55–79)
 FVC (absolute, L)3.41 (2.34–4.13)
 FVC (% predicted)63 (56–80)
 FEV1/FVC (absolute)86 (81–86)
 FEV1/FVC (% predicted)100 (95–107)
Peak VO2
 Absolute (cc/kg/min)22.1 (17.8–25.0)
 % predicted53 (46–68)
VO2 at anaerobic threshold
(% of peak predicted)
37 (34–49)
VE/VCO2 at anaerobic threshold34 (30–43)
Peak RER1.07 (1.04–1.16)
  • Data expressed as median (IQR) and absolute number (%).

  • *Cardiopulmonary function tests within 6 months of study entry are shown.

  • BMI, body mass index; CMR, cardiovascular magnetic resonance; CO, cardiac output; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; HV, hepatic vein; PBF, pulmonary blood flow; PoV, portal vein; RER, respiratory exchange ratio; Sub-IVC, subhepatic inferior vena cava; Sup-IVC, suprahepatic inferior vena cava; SVC, superior vena cava; VE/VCO2, ventilatory efficiency; VO2, oxygen consumption.