Group 4 Pulmonary hypertension due to CTEPH ‐ PDE5i vs placeboMortality ‐ sildenafil versus placebo · people with pulmonary hypertension due to CTEPH1 finding from 1 reviewPhosphodiesterase 5 inhibitors for pulmonary hypertension 2019 · Cochrane Headline outcomes onlyno estimate extracted1 study · 20 participantsLow