Mixed venous oxygen tension is a crucial prognostic factor in pulmonary hypertension: a retrospective cohort study

Table 1 Characteristics of patients with PAH stratified by PvO₂ of 35 mmHg

Variable	PvO₂		P
Variable	≥ 35 mmHg	< 35 mmHg	P
N	85	53
Age (years)	48.0 ± 17.5	53.6 ± 14.6	0.066
Sex (F/M)	70/15	43/10	0.856
RAP (mmHg)	4.6 ± 3.7	6.8 ± 4.7	0.005
mPAP (mmHg)	42.0 ± 10.8	51.8 ± 14.1	< 0.001
CI (L/min/m²)	3.1 ± 0.7	2.2 ± 0.6	< 0.001
PVR (W.U)	7.8 ± 3.5	14.4 ± 7.7	< 0.001
PaO₂ (mmHg)	77.2 ± 11.6	62.5 ± 12.1	< 0.001
PvO₂ (mmHg)	39.0 ± 2.8	31.0 ± 2.6	< 0.001
SvO₂ (mmHg)	72.0 ± 5.2	58.5 ± 7.1	< 0.001
A-aDO₂ (mmHg)	26.9 ± 11.9	43.4 ± 13.1	< 0.001
BNP (pg/mL)	128.0 ± 235.5	460.0 ± 523.0	< 0.001
6MWD (m)	395.6 ± 106.3	306.8 ± 100.0	< 0.001
FVC, %pred. (%)	87.2 ± 16.8	81.4 ± 22.5	0.140
DLCO, %pred. (%)	61.8 ± 20.1	50.9 ± 22.9	0.011
WHO functional class I, II, III, IV	6/44/34/1	0/16/29/8	< 0.001
Medical treatment	63 (74.1%)	41 (77.4%)	0.667
Combination pulmonary vasodilators, n (%)	36 (42.4%)	21 (39.6%)	0.751
ERA, n (%)	44 (51.8%)	23 (43.4%)	0.339
PDE5-I, n (%)	38 (44.7%)	23 (43.4%)	0.880
Prostacyclin, n (%)	38 (44.7%)	29 (54.7%)	0.252
sGCS, n (%)	5 (5.9%)	2 (3.8%)	0.583

Statistically significant, P < 0.05, are shown in bold
Data are presented as mean ± standard deviation or numbers
A-aDO₂ alveolar-arterial oxygen gradient, BNP brain natriuretic peptide, CI cardiac index DLCO, %pred. percent predicted carbon monoxide diffusing capacity, ERA endothelin receptor antagonists, FVC, %pred. percent predicted forced vital capacity, mPAP mean pulmonary arterial pressure, PAH pulmonary arterial hypertension, PaO₂ arterial oxygen tension, PDE5-I phosphodiesterase type 5 inhibitors, PvO₂ mixed venous oxygen tension, PVR pulmonary vascular resistance, RAP right arterial pressure, sGCS soluble guanylate cyclase stimulator, SvO₂ mixed venous oxygen saturation, WHO World Health Organization, W.U Wood units, 6MWD 6-min walk distance

ISSN: 1471-2466