Idiopathic pulmonary arterial hypertension patients with a high H₂FPEF-score: Insights from the Amsterdam UMC PAH-cohort

Background: The idiopathic pulmonary arterial hypertension (iPAH) phenotype is changing from a predominantly young female patient to an older, frequently obese patient of either sex. Many newly diagnosed iPAH-patients have risk factors for left ventricular diastolic dysfunction (LVDD), possibly affecting management and treatment.

Aim: To determine whether the H₂FPEF-score identifies a subgroup of iPAH-patients with blunted response to PAH-targeted treatment.

Study design and methods: We performed a retrospective analysis of 253 treatment-naïve iPAH-patients (1989-2019) with a confirmed diagnosis after right heart catheterization by a multidisciplinary team. Follow-up RHC measurements were available in 150 iPAH-patients. iPAH-patients were stratified by the H₂FPEF-score; a score ≥5 identified a higher possibility of (concealed) LVDD.

Results: The presence of a high H₂FPEF-score in incident iPAH-patients rose 30% in thirty years. Patients with a H₂FPEF-score ≥5 were older, more often male and/or obese, and had more comorbidities than patients with a H₂FPEF-score ≤1. A high H₂FPEF-score was associated with worse survival and poor functional capacity. Right ventricular function was equally depressed among iPAH-groups. Imaging and invasive hemodynamic measurements suggested concealed LVDD in iPAH patients with a high H₂FPEF-score. At follow-up, hemodynamic and functional responses were similar in iPAH-patients with a high or low H₂FPEF-score.

Conclusions: While a high H₂FPEF-score in iPAH is associated with a worse prognosis and signs of LVDD, hemodynamic and functional responses to PAH treatment are not predicted by the H₂FPEF-score.