| First author [ref.] | Study type (number treated) | Therapy (number treated) | Outcomes |
| Preston [27] | Prospective observational (8) | Inhaled NO (5), inhaled NO with i.v. EPO (1), CCBs (2) | Short-term 20% decrease in PVR and mPAP; long-term increase in 6MWT |
| Baughman [50] | Prospective open label 16 weeks (22) | Inhaled iloprost (15) | 6 out of 15 patients showed a decrease in mPAP/PVR, 3 out of 15 showed improvement in 6MWT |
| Fisher [51] | Retrospective case series (7) | i.v. EPO (6), s.c. treprostinil (1) | Improved NYHA class |
| Barnett [52] | Retrospective case series (22) | i.v. EPO (1), bosentan (12), sildenafil (9) | Improved 6MWT, NYHA class reduction in mPAP and PVR |
| Milman [53] | Retrospective chart review (12) | Sildenafil (12) | Decrease in mPAP/PVR, increase in cardiac output, no change in 6MWT |
| Culver [54] | Retrospective chart review (7) | Bosentan (3), bosentan and i.v. EPO (4) | Reduction in mPAP at 6–18 months in half of the patients |
| Baughman [30] | Retrospective chart review (5) | Bosentan (5) | Reduction in mPAP from 50 mmHg to 35 mmHg in 3 out of 5 patients at 4 months |
| Judson [55] | Prospective placebo-controlled 12 weeks (20) | Ambrisentan (17 patients at 4 weeks, 12 patients at 8 weeks and 7 patients at 12 weeks) | No change in 6MWT, 9 patients discontinued drug |
NO: nitric oxide; i.v.: intravenous; EPO: epoprostenol; CCB: calcium channel blocker; PVR: pulmonary vascular resistance; mPAP: mean pulmonary artery pressure; 6MWT: 6-min walking test; NYHA: New York Heart Association; s.c.: subcutaneous.