Table 3– Anthropometric characteristics, cardiovascular variables obtained during resting right heart catheterisation under pharmacotherapy, and resting pulmonary function testing in pulmonary arterial hypertension (PAH) patients who developed dynamic lung hyperinflation during exercise (PAH-H) and those who did not (PAH-NH), and in controls

	PAH-H	PAH-NH	Controls
Subjects n	15	10	10
Female/male n	9/6	6/4	5/5
Age yrs	40±11	35±13	39±16
Height cm	167±8	169±9	171±9
Body mass index kg·m⁻²	25±3	22±3	23±4
Duration of disease months	70±59	79±78
NYHA functional class	2±1	2±1
6MWD m	523±84	568±113
mPAP mmHg	48±13	50±22
Right atrial pressure mmHg	5±3	7±4
P_pcw mmHg	8±4	9±2
PVR Wood units	6.1±2.5	7.3±3.5
CO L·min⁻¹	6.7±1.2	5.9±1.1
CI L·min⁻¹·m⁻²	3.7±0.6	3.5±0.7
Mixed venous oxygen saturation %	72±6	71±6
Resting pulmonary function
FEV₁ L (% pred)	2.8±0.7^¶ (88±17)^¶	3.3±0.9 (95±14)⁺	4.0±0.7 (116±11)
FVC L (% pred)	3.4±1.0^¶ (91±17)^¶	3.9±1.0 (97±17)⁺	4.7±0.8 (116±10)
FEV₁/VC^# %	113±11	117±9	110±5
TLC L (% pred)	5.2±1.1^¶ (92±11)^¶	5.6±1.1 (96±10)	6.4±0.9 (107±9)
VC L (% pred)	3.6±1.1^¶ (93±18)^¶	4.0±1.0 (96±16)	4.7±0.8 (113±10)
FRC L (% pred)	2.6±0.5^¶ (89±10)^§,¶	3.1±0.6 (103±14)	3.2±0.7 (104±16)
IC L (% pred)	2.6±0.8 (98±22)	2.5±0.6 (90±17)	3.2±0.4 (108±18)
RV L (% pred)	1.6±0.5 (93±24)	1.6±0.4 (94±23)	1.7±0.5 (95±17)
ERV L (% pred)	1.0±0.4^§,¶ (83±31)^§,¶	1.5±0.6 (114±43)	1.5±0.6 (115±34)
FEF_25% L·s⁻¹ (% pred)	6.5±1.7 (98±18)	7.0±1.9 (102±11)	7.6±1.8 (108±10)
FEF_50% L·s⁻¹ (% pred)	3.7±0.9^¶ (85±20)^¶	4.5±1.4 (95±19)	5.1±1.0 (109±18)
FEF_75% L·s⁻¹ (% pred)	1.1±0.4^§,¶ (56±15)^§,¶	1.9±0.9 (89±25)	2.2±0.7 (105±8)

Data are presented as mean±sd, unless otherwise stated. NYHA: New York Heart Association; 6MWD: 6-min walking distance; mPAP: mean pulmonary artery pressure; P_pcw: pulmonary capillary wedge pressure; PVR: pulmonary vascular resistance; CO: cardiac output; CI: cardiac index; FEV₁: forced expiratory volume in 1 s; % pred: % predicted; FVC: forced vital capacity; VC: vital capacity; TLC: total lung capacity; FRC: functional residual capacity; IC: inspiratory capacity; RV: residual volume; ERV: expiratory reserve volume; FEF_{25%, 50% and 75%}: forced expiratory flow at 25%, 50% and 75%, respectively, of the FVC. p<0.05 (one-way ANOVA): ^#: spirometric evidence of an obstructive ventilatory defect as defined by a reduced FEV₁/VC ratio below the fifth percentile of the predicted value [15]; ^¶: PAH-H versus controls; ⁺: PAH-NH versus controls; ^§: PAH-H versus PAH-NH.