Association of PH-Targeted Therapy and Survival in Precapillary PH with mPAP between 21 and 24 mmHg

Introduction . Pulmonary hypertension (PH) definition was recently changed and led to a new subset of PH patients with mildly impaired pulmonary hemodynamics, characterized by a mean pulmonary artery pressure of 21–24 mmHg and with a pulmonary vascular resistance >2Wood Units. We evaluated the association of PH-targeted therapy and outcome in mild precapillary PH using the PVRI GoDeep meta-registry. Methods . All patients with mild precapillary PH (mPAP 21–24 mmHg, PAWP ≤15 mmHg, PVR >2WU) diagnosed with PAH and CTEPH were enrolled. Patients were considered treated if PH-targeted therapy was initiated within 6 months of diagnostic right heart catheterization. Various statistical models, including in-depth sensitivity analyses, were used to examine the association between PH-targeted therapy and transplant-free survival. Results . 132 patients with group 1 or group 4 mild PH were identified, of whom 34 patients received PH-targeted therapy. There were no differences in baseline hemodynamics between untreated and treated groups, while treated patients suffered more frequently from renal comorbidities and required long-term oxygen treatment more often. Most prescribed were phosphodiesterase-5-inhibitors. PH-targeted therapy was associated with significantly higher survival rates, compared to those without treatment. Cox-regression analysis revealed significantly reduced hazard ratios among treated patients in Cox-regression analyses adjusted for various confounders. Subgroup analyses in PAH (n=78) similarly indicated higher survival rates and reduced hazard ratios in treated patients. Conclusion . PH-targeted therapy may be associated with improved survival in PAH and CTEPH patients with mild PH. To mitigate potential bias of the results due to the retrospective study design, randomized controlled trials are warranted.