Table 2– Univariate analysis relating survival time with selected variables at baseline and after atrial septostomy (AS) in the total group

Variable	HR (95% CI)	p-value
Age yrs	1.01 (0.97–1.06)	0.355
Female sex	1.68 (0.50–5.68)	0.397
AS size	0.99 (0.83–1.18)	0.942
RVEDP
Before AS	1.04 (0.97–1.11)	0.257
After AS	1.01 (0.95–1.08)	0.634
LVEDP
Before AS	1.08 (0.94–1.25)	0.255
After AS	1.02 (0.86–1.20)	0.785
P̄_pa
Before AS	1.00 (0.97–1.03)	0.573
After AS	0.99 (0.97–1.02)	0.912
Cardiac index
Before AS	0.38 (0.08–1.65)	0.200
After AS	0.90 (0.48–1.66)	0.741
S_a,O₂
Before AS	0.94 (0.82–1.07)	0.407
After AS	0.92 (0.85–0.98)	0.020
<85% after AS	2.18 (0.87–5.4)	0.089
6MWT
Before AS	0.98 (0.97–0.99)	0.031
After AS	0.99 (0.98–0.99)	0.014
WHO FC
Before AS	1.75 (0.84–3.67)	0.133
After AS	2.68 (1.08–6.66)	0.033
Pharmacological treatment after AS	0.31 (0.12–0.80)	0.015

HR: hazard ratio; RVEDP: right ventricular end-diastolic pressure; LVEDP: left ventricular end-diastolic pressure; P̄_pa: mean pulmonary artery pressure; S_a,O₂: arterial oxygen saturation; 6MWT: 6-min walk test; WHO: World Health Organization; FC: functional class.