Pulmonary arterial hypertension with cardiopulmonary comorbidities: is it a unique phenotype?

Abstract

Background: Pulmonary arterial hypertension (PAH) patients with cardiopulmonary comorbidities have been prevalent nowadays. However, there was limited data on clinical characteristics and therapeutic responses in these populations.

Methods: Patients diagnosed with right heart catheterization (RHC)-confirmed PAH between October 2021 to March 2023 were included in our study. According to whether they had cardiopulmonary diseases or not, they were classified into two groups: comorbidities group and non-comorbidities group. We aimed to compare the clinical data, PAH-targeted strategies, and therapeutic responses between these two PAH groups. We further analyzed the impact of the numbers and categories of comorbidities on therapeutic responses.

Results: Almost half of the patients co-existed with cardiopulmonary diseases. Compared with non-comorbidities group (n = 40), comorbidities group (n = 36) were senior (p = 0.000) and male predominantly (p = 0.005). Comorbidities group also associated inconsistencies between hemodynamics and 6-min walking distance (6MWD), with a shorter 6MWD (p = 0.000), but a lower mean pulmonary artery pressure (mPAP) (p = 0.008). Non-comorbidities group showed an upturn in the WHO-FC (p = 0.010) and risk assessment (p = 0.033), while the improvement of hemodynamics [decreased mPAP (p = 0.009) and pulmonary vascular resistance (PVR) (p = 0.001), increased cardiac index (p = 0.001)] in comorbidities group did not match the change in clinical severity (no significant improvements in WHO-FC, risk stratification and 6MWD). When categorized by the comorbidities counts, it demonstrated that the more comorbidities, the more severe the clinical conditions, and the worse the therapeutic responses.

Conclusion: PAH patients with cardiopulmonary comorbidities represent a unique phenotype, with different clinical manifestation and treatment responses from typical PAH and inconsistencies between hemodynamics and functional status from baseline to follow-up.