The other types of pulmonary hypertension. 
Subjects who refuse to subscribe written informed consents or can't cooperate with the trial well. 
Subjects with serious acute or chronic disease involved liver, kidney, and brain or have to use potent CYP3A4-inhibitor or nitrate to treat the underlying diseases. 
Subjects who are currently treated with sildenafil for PAH or taking sildenafil or tadalafil. 
Other contraindications in package insert.       
    

NCT00718952_exc_T1
Condition
pulmonary hypertension
NCT00718952_exc_T3
Condition
chronic disease involved liver
NCT00718952_exc_T4
Temporal
acute
NCT00718952_exc_T5
Qualifier
serious
NCT00718952_exc_T6
Condition
chronic disease involved kidney
NCT00718952_exc_T7
Condition
chronic disease involved brain
NCT00718952_exc_T8
Scope
chronic disease involved liver, kidney, and brain
NCT00718952_exc_T9
Drug
CYP3A4-inhibitor
NCT00718952_exc_T10
Drug
nitrate
NCT00718952_exc_T11
Qualifier
potent
NCT00718952_exc_T12
Drug
sildenafil
NCT00718952_exc_T13
Condition
PAH
NCT00718952_exc_T14
Drug
sildenafil
NCT00718952_exc_T15
Drug
tadalafil
NCT00718952_exc_T16
Observation
contraindications in package insert
NCT00718952_exc_T2
Observation
refuse to subscribe written informed consents
NCT00718952_exc_T17
Observation
can't cooperate with the trial
NCT00718952_exc_T18
Condition
underlying diseases
NCT00718952_exc_T19
Scope
CYP3A4-inhibitor or nitrate
NCT00718952_exc_T20
Qualifier
other types
NCT00718952_exc_T21
Temporal
currently
NCT00718952_exc_T22
Scope
sildenafil for PAH or taking sildenafil or tadalafil