The goal of this retrospective observational study is to evaluate if lung distension disorders can be a predictive factor of bad response to vasodilator therapy in patients with pulmonary hypertension (PH) associated with chronic obstructive pulmonary disease (COPD).

The study will include all patients from the hospital, followed for pulmonary hypertension associated with COPD under vasodilator therapy between 2015 and 2021.

The goal of this retrospective observational study is to evaluate if lung distension disorders can be a predictive factor of bad response to vasodilator therapy in patients with pulmonary hypertension (PH) associated with chronic obstructive pulmonary disease (COPD).

The study will include all patients from the hospital, followed for PH associated with COPD under vasodilator therapy between 2015 and 2021.

It will evaluate patients' lung hyperinflation according to the RV/TLC ratio and their response to treatment.

Inclusion Criteria:

• Patients with COPD regardless of severity defined as a FEV1/FVC ratio less than 0.70 and the presence of a risk factor (smoke exposure with at least a 10 pack-year history, or professional exposition) diagnosed with PH according to ESC/ERS 2022 classification and in whom vasodilator therapy has been initiated

Exclusion Criteria:

• other known concomitant lung disease (interstitial lung disease, cystic lung disease, mucoviscidosis…)
• thoracic pathology such as kyphoscoliosis
• pleural effusion (unless part of pulmonary veno-occlusive disease)
• a large tumor lung mass
• EFR missing or uninterpretable because difficult to perform
• initiation of calcium channel blockers
• surgical treatment in chronic thrombo-embolic pulmonary hypertension
• no follow-up evaluation (lost to follow-up or died before reassessment)

All patients with pulmonary hypertension associated with COPD undergoing vasodilator therapy at Nancy University Hospital (France) from January 1, 2015 to April 1, 2023.