Abstract
BACKGROUND: This study aimed to evaluate the progress of treatment with intensive targeted therapy in high-risk pulmonary arterial hypertension (PAH) patients and focused on setting an appropriate hemodynamic target of pulmonary vascular resistance (PVR) ≤4 Wood units (WU) and mean pulmonary arterial pressure (mPAP) ≤ 40 mmHg. METHODS: We retrospectively evaluated high-risk PAH patients who were administered treprostinil at a single tertiary pulmonary hypertension center between January 2020 and December 2022. Echocardiography, right heart catheterization, 6-minute walk distance (6MWD), and blood tests were obtained 6 and 12 months after the initiation of parenteral treprostinil administration. RESULTS: Twelve patients (1 male and 11 female; median age, 47.0 years [interquartile range, 33.8-49.8 years]) were included. Five of the 12 patients had 6- and 12-month follow-up data. The median PVR decreased by 22.9% at 6 months and 50.6% at 12 months compared to baseline. The median mPAP decreased by 24.6% at 6 months and 29.8% at 12 months. Importantly, the 6MWD showed a significant improvement of 55.7%, and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels demonstrated a notable decrease of 16.0%, reflecting substantial enhancements in patients' functional status and heart health. Three of these 5 patients reached the hemodynamic target by 12 months and successfully transitioned from parenteral treprostinil to oral selexipag. CONCLUSIONS: This study showed that 3 of 5 patients (60.0%) with high-risk PAH reached PVR ≤ 4 WU and/or mPAP ≤ 40 mmHg by receiving intensive parenteral treprostinil therapy with significant improvements in 6MWD and NT-proBNP levels, and successfully transitioned to oral selexipag. We proposed that transition strategies from parenteral treprostinil to selexipag aiming at hemodynamic targets.