Characteristics and management of chronic thromboembolic pulmonary disease patients without pulmonary hypertension in an expert centre

Introduction: Data regarding chronic thromboembolic pulmonary disease (CTEPD) without pulmonary hypertension (PH) and its management are scarce. Method: This study describes the characteristics and outcome of a cohort of CTEPD patients without PH according to the type of management, in the French PH referral centre. Demographics were compared to a cohort of 426 CTEPH patients treated meanwhile. Results: 39 CTEPD without PH patients were evaluated from 2015 to 2020 (mean pulmonary artery pressure 20.6 (±3.3) mmHg and pulmonary vascular resistance 153 (±48) dyn.s.cm-5). CTEPD without PH patients were younger (p<0.0001) and more likely to have had a previous pulmonary embolism (p<0.01), when compared to CTEPH patients. 22 CTEPD without PH patients (56%) were deemed operable and 12 underwent pulmonary endarterectomy (PEA), which significantly improved symptoms (p<0.05) and hemodynamics (p=0.015). PEA was associated with a rate of transient complications of 33%. Among the 17 inoperable patients (44%), 4 underwent balloon pulmonary angioplasty, which improved symptoms. 22 of 39 patients (56%) were followed without intervention. This subgroup was less symptomatic (p=0.02) and had a higher cardiac index (p=0.02), when compared to the interventional subgroup. Untreated patients remained clinically stable after a median follow-up of 42 months. Conclusions: CTEPD without PH patients should be thoroughly assessed prior to instrumental treatment. PEA significantly improves symptoms and hemodynamics but is associated with a substantial rate of complications. A subgroup of CTEPD without PH patients appears clinically stable when treated conservatively.