Reddy, Y N V

Abstract Rationale The pathophysiology and clinical impact of liver injury in pulmonary hypertension (PH) is poorly understood. Liver injury in PH is often attributed to hepatic congestion, but some studies have failed to find strong associations with hemodynamics, suggesting alternative mechanisms. We sought to define the prevalence of liver injury and patterns of liver injury across the spectrum of PH and to determine whether patterns of liver injury were associated with clinical characteristics, hemodynamics and outcomes. Methods We performed an analysis of the PVDOMICS study, a multicenter, prospective, longitudinal cohort study that enrolled incident and prevalent patients with PH and disease comparators. The prevalence of liver injury, defined as aspartate or alanine aminotransferase (AST or ALT) or total bilirubin above the upper limit of normal, and different patterns of liver injury [hepatocellular (elevated AST or ALT with normal bilirubin), cholestatic (elevated bilirubin) and no liver injury] was defined among participants with known or suspected PH. Associations between patterns of liver injury with demographics, hemodynamics, right ventricular function, exercise capacity and quality of life (QoL) were assessed. We used Cox proportional hazards models adjusted for age and sex to assess the association of liver injury patterns with transplant-free survival. Results Liver injury was present in 27.8% (288/1036) of participants (19.0% cholestatic and 8.8% hepatocellular). Patients with liver injury were less likely to be female and have prevalent disease with differences in PH classification (Table 1). Patients with hepatocellular liver injury had a higher body mass index. A cholestatic liver injury pattern was most consistently associated with worse functional class, biventricular filling pressures, pulmonary vascular resistance, right ventricular function, natriuretic peptide elevation, exercise capacity, and REVEAL risk scores. Total bilirubin levels and right atrial pressure as a marker of systemic congestion were weakly correlated (r2=0.02, p < 0.0001). Compared to no liver injury, cholestatic liver injury was associated with an increased risk of death in age and sex adjusted models (HR 1.6, 95% CI 1.3-2.1, p < 0.001) but hepatocellular liver injury was not (p > 0.05). Conclusions Liver injury is common among patients with known or suspected PH. In contrast to a hepatocellular injury pattern, a cholestatic liver injury pattern was most consistently associated with worse hemodynamics, exercise capacity, QoL and survival. However, the weak relationship between right atrial pressure and bilirubin suggests that systemic congestion alone is unlikely to completely explain cholestatic liver injury. Further study is needed to uncouple the pathophysiological basis of cholestasis in PH. This abstract is funded by: NHLBI

Abstract Rationale Sotatercept is a novel activin signaling inhibitor approved for the treatment of pulmonary arterial hypertension (PAH). Sotatercept has been studied in randomized clinical trials, but little is known regarding the real-world use of sotatercept. We sought to describe the safety, tolerability and efficacy of sotatercept in our clinical practice. Methods We performed a combined prospective and retrospective cohort study of all patients treated with sotatercept at Mayo Clinic Rochester since its approval in March 2024. Patients enrolled in a separate clinical trial of sotatercept were excluded from this analysis as their data will be reported separately. Clinical data was abstracted from the electronic health record. Follow-up data was collected at 6 ± 3 months after initiation of sotatercept. Data is summarized as n (%) and mean ± SD. We used paired t-tests to compare baseline and follow-up characteristics within individuals. Results Fifty-eight PAH patients treated with sotatercept were included. Patients were 48.4 ± 37.6 years old at treatment initiation and were predominantly female with a mean duration of PAH of 6.7 years and a range of PAH etiologies including portopulmonary hypertension, congenital heart disease, and pulmonary veno-occlusive disease (Table 1). Twenty-one (36%) of patients had mixed etiologies of PH. Six months after initiation of sotatercept, patients had a significant improvement in NTproBNP (1922 ± 4464 to 363 ± 596 pg/ml, p = 0.04), 6 minute walk distance (378.8 ±144.6 to 395.7±129.5 meters, p = 0.02) and right ventricular systolic pressure (74.6 ± 20.5 to 60.6 ± 20.3 mm Hg, p < 0.001). No patients permanently discontinued due to abnormal laboratory values. Mean highest hemoglobin achieved over the initial 6 months of treatment was 15.5 ± 2.1 g/dL and mean lowest platelet count was 181 ± 74K. Seven patients discontinued sotatercept at a range of 170-275 days after starting. Four patients discontinued due to possible treatment-related adverse effects: 1 each of gastrointestinal hemorrhage, retinal hemorrhage, hypoxia/intrapulmonary vasodilatation and spontaneous bilateral subdural hematomas. Three patients discontinued due to other reasons: newly diagnosed metastatic cancer leading to transition to hospice and two due to lack of improvement. Conclusions In this real-world registry of sotatercept in PAH, sotatercept was well-tolerated among patients with PAH and associated with improvements in exercise capacity, echocardiographic parameters, and NTproBNP. Overall discontinuation due to possible treatment-related adverse effects was low and reasons for discontinuation included bleeding and hypoxia attributed to intrapulmonary vasodilatation. This abstract is funded by: None