Table 3.
The effects of low vs high dose regimen of sildenafil on exercise capacity and echocardiographic variables
| Sildenafil | |||
|---|---|---|---|
| Low dose effect (Baseline – 3 months) | High-dose effect (3 months – 6 months) | Overall treatment effect | |
| 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)** |
Е Early inflow velocity, e′ Annulus relaxation velocity, IVC inferior vena cava, LV left ventricular, OT outflow tract, PVR Pulmonary vascular resistance, RV Right ventricular; TAPSE Tricuspid annular plane systolic excursion
* — P < 0.05, ** — P < 0.01 vs baseline
† — р < 0.05, and †† — р < 0.01 vs 3 month exam