Sildenafil in primary pulmonary hypertension--is there a subset of patients who respond favourably?

Recently, case reports of patients with primary pulmonary hypertension (PPH) treated with sildenafil demonstrated encouraging results. The mechanism proposed is a relatively selective pulmonary vasodilation via increased levels of cGMP because of the inhibition of phosphodiesterase type 5. Two siblings with a similar medical history, severe symptoms and elevated levels of pulmonary artery pressures were diagnosed with PPH after a thorough diagnostic work-up. Both patients were treated with coumadin, sildenafil, furosemide, spironolactone and digoxin. One of the patients had no improvement during the hospital course and died two months after discharge. The other patient improved dramatically during the hospital course, and this improvement was sustained. At the three-month follow-up control, she was much improved in terms of clinical status and echocardiographic findings.