PB1010 - Exercise could reveal pulmonary vascular abnormalities in patients with chronic thromboembolic pulmonary disease - a hemodynamic study

Background: Many patients with chronic thromboembolic pulmonary disease without pulmonary hypertension at rest (CTEPD) report exercise intolerance. Exercise right heart catheterization (excRHC) could reveal pulmonary vascular abnormalities not evident at rest but data are scarce.

Aims: Our aim is to characterize pulmonary hemodynamics by exercise in patients with CTEPD and to explore the prevalence of exercise induced pulmonary hypertension

Methods: 47 symptomatic patients all diagnosed after pulmonary embolism (PE) underwent exercise right heart catheterization. After hemodynamic categorization we compared the results of patients with chronic thromboembolic pulmonary hypertension (CTEPH, n=5), chronic thromboembolic pulmonary disease with EIPH (CTEPD EIPH, n=8), chronic thromboembolic pulmonary disease without EIPH (CTEPD, n=21) and controls (n=6). The diagnosis of pulmonary hypertension (PH) at rest and during exercise (EIPH) was defined according to the ESC guidelines on pulmonary hypertension of 2022.

Results: 8/29 patients (28%) with CTEPD were diagnosed with EIPH. 5/47 (11%) patients were diagnosed with CTEPH. 21 out of 47 patients (45%) had CTEPD with neither PH nor EIPH. We also found that 4/8 (50%) patients with CTEPD EIPH and 3/5 (60%) patients with CTEPH had an abnormal (PAWP) response pointing towards a post-capillary cause of EIPH.

Conclusion(s): EIPH is common in CTEPD and more than one quarter of the patients with CTEPD have abnormal hemodynamic responses in the pulmonary circulation during exercise that could contribute to their exercise intolerance