Alterations in gut microbiota and plasma metabolites in pulmonary arterial hypertension secondary to congenital left-to-right shunt heart disease: potential mechanisms and biomarkers

CL-RSHD-associated PAH involves gut microbial restructuring and metabolic reprogramming linked to immune-inflammatory activation and oxidative stress. The Firmicutes-histidine metabolism axis emerges as a therapeutic target. Despite limitations, this study provides foundational insights into microbial-metabolic drivers of PAH, highlighting novel biomarkers for early diagnosis and intervention.