Does pulmonary endarterectomy improve the clinical conditions of patients with chronic thromboembolic pulmonary disease without pulmonary hypertension?

To verify whether the new hemodynamic definition of pulmonary hypertension (PH) has any implication in treatment of Chronic Thrombo-Embolic Pulmonary Disease (CTEPD) patients without PH, we retrospectively analysed the clinical and functional changes determined by pulmonary endarterectomy (PEA) in 63 CTEPD patients without PH who underwent surgery at our center, comparing those in whom the hemodynamic diagnosis of PH met recent guideline recommendations versus those in whom the diagnosis only met previous hemodynamic thresholds. The results show that the vast majority of CTEPD patients without PH operated at our center would now be defined as chronic thromboembolic pulmonary hypertension (CTEPH) patients. PEA did not result in any improvement in exercise capacity nor in right ventricular function or lung function test in patients with mean pulmonary artery pressure (mPAP) ≤ 20 mm Hg and pulmonary vascular resistance (PVR) ≤ 2 WU; on the contrary, hemodynamic parameters, exercise capacity, right ventricular function and lung function significantly improved in patients with mPAP between 21 and 24 mm Hg.