Table 3 The effects of low vs high dose regimen of sildenafil on exercise capacity and echocardiographic variables

PVR, Wood units

−0.56 (95% CI − 0.70 to − 0.42)^**

−0.09 (95% CI − 0.20 to 0.02)

−0.65 (95% CI − 0.76 to − 0.53)^**

RVOT acceleration time, ms

29 (95% CI 20 to 38)^**

2 (95% CI −5 to 10)

31 (95% CI 23 to 40)^**

TAPSE, cm

0.25 (95% CI 0.18 to 0.31)^**

0.17 (95% CI 0.10 to 0.25)^††

0.42 (95% CI 0.32 to 0.52)^**

RV basal diameter, cm

−0.18 (95% CI − 0.26 to − 0.10)^**

−0.12 (95% CI − 0.21 to − 0.04)^††

−0.30 (95% CI − 0.42 to − 0.18)^**

Mitral e′, cm/s

0.8 (95% CI 0.5 to 1.0)^**

0.2 (95% CI − 0.1 to 0.5)

1.0 (95% CI 0.6 to 1.3)^**

Mitral E/e′ ratio

−1.2 (95% CI − 2.0 to − 0.5)^**

−1.1 (95% CI − 1.8 to − 0.4)^††

− 2.4 (95% CI − 3.3 to − 1.4)^**

LV mass index, g/m²

−12 (95% CI − 21 to − 4)^**

−12 (95% CI − 20 to − 4)^††

−24 (95% CI − 34 to − 14)^**