Background: Treprostinil (TRE), a prostacyclin analog, is effective for the treatment of pulmonary arterial hypertension and chronic thromboembolic pulmonary hypertension (CTEPH).  We hypothesized that change of hemodynamics is of prognostic value.  In our prospective registry we evaluated effects of first-line subcutaneous (sc) TRE in patients with severe pulmonary hypertension (PH) and analyzed the prognostic value of hemodynamic response at 1 year on long-term follow-up.
 
Methods: Data was collected from patients with pre-capillary PH in WHO functional class III or IV, mean right atrial pressure of ³ 10mmHg, and/or cardiac index £ 2.2 liters/min/m2.  Patients received first-line scTRE.  Dose adjustments were performed individually according to clinical symptoms and side effects.
 
Results: Between 1999 and 2019 145 patients were included into the study.  Of these, 18 (12,4%) patients underwent double lung transplantation, and 59 (40.6%) died of any cause.  Overall survival rates at 1, 5, 10, and 15 years were 91%, 57%, 31% and 29%.  The strongest predictor of outcome was change in mPAP after one year of scTRE.  Change in mPAP -18.4 ± 7.9 mmHg (P=0.012) was associated with the best subsequent survival of 12.7 ±1.5 years.

Conclusion: Aggressive lowering of mPAP in the first year of treatment correlated with better survival.