Clinical and Hemodynamic Implications of the 2022 Definition in Connective Tissue Disease-Associated Pulmonary Arterial Hypertension

Introduction/Objectives: The 2022 pulmonary hypertension guidelines lowered the hemodynamic thresholds for pulmonary hypertension and pulmonary arterial hypertension, potentially expanding the spectrum of connective tissue disease-associated pulmonary arterial hypertension (CTD-PAH). The profile of patients identified only by the updated definition remains incompletely characterized. To evaluate the reclassification impact of the 2022 hemodynamic definition in a catheterization-based cohort of clinically adjudicated CTD-associated Group 1 PAH.Methods: We retrospectively analyzed 27 patients with CTD-associated Group 1 PAH. Patients fulfilling previous mPAP and PVR thresholds were classified as established PAH, whereas those fulfilling the 2022 classification but not the previous definition were classified as 2022-only early CTD-PAH. Clinical, pulmonary function, echocardiographic, and hemodynamic variables were compared. Exploratory high burden was defined as ≥4 positive components among PVR ≥5 WU, mPAP ≥35 mmHg, right atrial mean pressure ≥8 mmHg, cardiac index