CONGRESS ABSTRACT

Introduction : several studies indicate a relationship between chronic cardiovascular disease and sarcopenia, but its expression in different pulmonary hypertension (PH) subgroups is still unknown. Our study aims to identify loss of muscle mass in different subgroups of PH, exploring the correlation with different hemodynamic parameters, using the skeletal muscle index (SMI) and the intramuscular fibroadipose tissue (IMAT) derived by the chest high resolution computed tomography (HRCT) scan to evaluate muscles such as pectoral muscles (PM) and erector spinae muscle (ESM). Methods : we included in this retrospective monocentric cohort study 914 patients, corresponding to a total of 1188 right heart catheterization (RHC) performed between 2009 and 2021. We excluded patients with missing data (11 patients, 1,2%) or those (168 patients, 14%) who did not respect the criteria for the diagnosis of PH. Furthermore, we have excluded repeated RHC (274, 27,15%) from the study by focusing exclusively on the first RHC performed for each patient, resulting in a total of 735 RHCs included in the study. Of these, 235 (32%) were identified as belonging to Group 1 PH, 192 (26%) belonged to Group 2 PH, and the remaining 308 (42%) belonged to Group 3 PH. Moreover, only 294 patients underwent HRCT, distributed as 123 in Group 1, 55 in Group 2, and 116 in Group 3. Results : Our results showed that IMAT was higher in Group 2 (4.85±2.94 cm²) compared to Group 1 (4.28±3.50), and both were higher than in Group 3 (3.29±2.19 cm²) (p<0.01). A subanalysis in Group 1 patients shows a positive correlation between PAPm and IMAT PM (r=0.133, p=0.012), IMAT ESM (r=0.168, p=0.002), IMAT PM/BSA (r=0.121, p=0.020), IMAT ESM/BSA (r=0.159, p=0.003) and IMAT (PM+ESM)/BSA (r=0.164, p=0.002). Regarding cardiac index (CI), we found a negative correlation with IMAT ESM (r=-0.176, p=0.001), IMAT ESM/BSA (r=-0.156, p=0.004) and IMAT (PM+ESM)/BSA (r=-0.132, p=0.012). Finally, TPVR shows a positive correlation with IMAT ESM (r=0.103, p=0.040) and IMAT ESM/BSA (r=0.117, p=0.023). Conclusion : These findings highlighted that PH is associated with myosteatosis, with a correlation with the increased afterload and reduced CI. This is particularly important because patients with PH tend to move less (mainly due to dyspnea), thereby promoting sarcopenia, which in turn worsens motor skills. This relationship constitutes a positive feedback loop that could worsen quality of life and prognosis.