Table 2—

The 6-min walking distance and clinical variables, resting haemodynamics parameters and 6MWT characteristics assessed at baseline in idiopathic and nonidiopathic PAH

	Idiopathic PAH^#		Nonidiopathic PAH^¶
	Regression coefficient	se	Regression coefficient	se
Clinical
Age yrs	−2.67**	0.84	−0.95	1.47
Height cm	4.14**	1.29	3.69	2.17
Weight kg	−0.82	0.93	−0.42	1.25
Haemodynamics
mRAP mmHg	−4.32	3.04	−6.78*	2.88
mPAP mmHg	−0.52	0.82	−2.58*	1.06
PAOP mmHg	−7.45	4.25	2.99	4.74
CO L·min⁻¹	39.15**	10.18	27.17**	9.68
SV mL	2.60**	0.65	2.85**	0.57
PVR mmHg·min·L⁻¹	−5.62*	2.75	−9.43**	3.22
S_v,O₂ %	4.93**	1.69	5.20**	1.43
HR beats·min⁻¹	−1.23	0.99	−4.76**	0.97
6MWT
S_P,O₂,rest %	7.77	4.02	12.24*	5.02
S_P,O₂,min %	−0.27	2.71	6.53*	2.83
ΔS_P,O₂ %	−4.35	2.93	4.29	3.78
HR_rest beats·min⁻¹	−0.44	0.91	−3.10**	0.98
HR_peak beats·min⁻¹	2.10**	0.67	−0.86	1.15
ΔHR beats·min⁻¹	3.12**	0.71	4.45**	1.34
Borg scale	−15.78	8.39	−18.72	13.61

6MWT: 6-min walk test; PAH: pulmonary arterial hypertension; se: standard error; mRAP: mean right atrial pressure; mPAP: mean pulmonary arterial pressure; PAOP: pulmonary arterial occlusion pressure; CO: cardiac output; SV: stroke volume; PVR: pulmonary vascular resistance; S_v,O₂: mixed venous oxygen saturation; HR: heart rate; S_P,O₂,rest: peripheral oxygen saturation measured at rest; S_P,O₂,min: minimal S_P,O₂ measured during 6MWT; ΔS_P,O₂: desaturation measured during the 6MWT (S_P,O₂,min–S_P,O₂,rest); HR_rest: heart rate measured at rest; HR_peak: peak heart rate measured during the 6MWT; ΔHR: chronotropic response (HR_peak–HR_rest). ^#: n = 46; ^¶: n = 37. *: p<0.05; **: p<0.01.