Table 1 Clinical characteristics and comparisons

N = 30

N = 21

N = 9

Age at baseline (years)

43.4 ± 13

43.4 ± 11.4

43.3 ± 17.8

0.99

Oxygen saturation (%)

81 ± 7

81 ± 7

81 ± 6

0.78

Female

20 (67%)

14 (67%)

6 (67%)

0.99

History of arrhythmia

3 (10%)

2 (9%)

1 (11%)

0.60

Hemoglobin (g/dl)

20 ± 2.6

20.3 ± 2.8

19.3 ± 2.1

0.34

Creatinine (μmol/l)

86 ± 24.6

86 ± 24

88 ± 28

0.81

Urea (mmol/l)

6.1 ± 2.8

5.9 ± 2.3

6.3 ± 3.5

0.75

Brain natriuretic peptide (pmol/l)*

15/14

14/24

15/13

0.99

RV ejection fraction (%)

51 ± 14

51 ± 13

50 ± 18

0.69

LV ejection fraction (%)

57 ± 11

59 ± 10

51 ± 12

0.06

P_ACO₂ (kPa)

4.4 ± 0.7

4.5 ± 0.6

4.1 ± 0.8

0.35

P_AO₂ (kPa)

6.4 ± 0.9

6.4 ± 0.9

6.4 ± 0.9

0.93

Exercise Duration (min)

5.7 ± 2.4

5.2 ± 2.1

6.2 ± 2.8

0.30

VO2 at peak (ml/kg/min)

11.1 ± 3.9

10.7 ± 3.5

11.9 ± 4.8

0.46

VE/CO₂slope

87 ± 69

96 ± 82

66 ± 18

0.29

% predicted peak VO₂

36 ± 11

35 ± 11

36 ± 13

0.70

6 minute walk distance (m)

388 ± 108

405 ± 110

348 ± 96

0.19

Death during follow up (yr)

7 (23%)

4 (19%)

3 (33%)

0.13