Sildenafil Dose
Placebo (n=60) Low (n=42) Medium (n=55) High (n=77) Combined (n=174)
Female sex, n (%) 38 (63) 25 (60) 31 (56) 51 (66) 107 (62)
Age in years, n (%)          
1–4 7 (11) 0 (0) 9 (16) 19 (25) 28 (16)
5–12 37 (62) 25 (60) 28 (51) 36 (47) 89 (51)
13–17 16 (27) 17 (40) 18 (33) 22 (29) 57 (33)
WHO functional class, n (%)          
I 25 (42) 9 (21) 20 (36) 21 (27) 50 (29)
II 29 (48) 23 (55) 25 (45) 43 (56) 91 (52)
III 6 (10) 9 (21) 8 (15) 12 (16) 29 (17)
IV 0 0 1 (2) 0 1 (1)
Missing 0 1 (2) 1 (2) 1 (1) 3 (2)
Etiology, n (%)          /td>
IPAH/FPAH 21 (35) 12 (29) 19 (35) 26 (34) 57 (33)
PAH-CHD 39 (65) 30 (71) 36 (65) 51 (66) 117 (67)
PAH-related variables, mean (SD)          
Peak VO2, mL/kg/min 20 (4) 18 (4) 18 (5) 17 (4) 18 (4)
Mean pulmonary artery pressure, mmHg 59 (22) 66 (23) 62 (18) 62 (24) 63 (22)
Cardiac index, L/min/m2§ 3.9 (2.1) 3.1 (1.1) 3.3 (1.5) 3.4 (1.6) 3.3 (1.5)
Pulmonary vascular resistance index, Wood units•m2 15 (10) 22 (13) 19 (14) 20 (16) 20 (15)
Note: CHD=congenital heart disease; FPAH=familial PAH; IPAH=idiopathic PAH; PAH=pulmonary arterial hypertension; VO2=oxygen consumption; WHO=World Health Organization.
*The groups shown represent all treated patients.
Subset of patients developmentally able to perform exercise testing (n=30, 28, 28, 29, and 85 for placebo, sildenafil low-, medium-, and high-dose groups, and sildenafil
combined dose group, respectively).
n=59, 42, 55, 75, and 172 for placebo, sildenafil low-, medium-, and high-dose groups, and sildenafil combined dose group, respectively.
§ n=59, 41, 52, 74, and 167 for placebo, sildenafil low-, medium-, and high-dose groups, and sildenafil combined dose group, respectively.
n=57, 40, 52, 73, and 165 for placebo, sildenafil low-, medium-, and high-dose groups, and sildenafil combined dose group, respectively.
Table 1: Baseline Patient Characteristics from STARTS-1*.