Popis: |
It is unsettled whether increased exercise ventilation in Fontan subjects is due to increased pulmonary dead space or augmented ventilatory drive. Twenty-six Fontan patients underwent symptom-limited treadmill cardiopulmonary exercise testing. Two groups of age- and sex- matched subjects served as controls: the biventricularly repaired (Bi, n = 18), and the “true” control (C, n = 29) groups. Peak oxygen uptake (VO2peak) was not different among groups (41.0 +/– 8.4 ml/min/kg, 43.5 +/– 6.6 ml/min/kg, and 45.9 +/– 11.6 ml/min/kg for Fontan, Bi, and C groups, respectively, p = 0.16). Fontan subjects, however, showed steeper alveolar ventilation/carbon-dioxide (VA/VCO2) regression slope (35.5 +/– 5.3, 28.7 +/– 3.8, and 29.5 +/– 3.0 l/ml, for Fontan, Bi, and C groups, respectively, p |