Eisenmenger Syndrome: Pathophysiology, Clinical Manifestations, and Contemporary Management Approaches in Advanced Cardiopulmonary Disease

Eisenmenger syndrome, a complex and severe form of congenital heart disease, results from prolonged left-to-right shunting due to underlying cardiac defects such as ventricular septal defects, atrial septal defects, or patent ductus arteriosus, ultimately leading to irreversible pulmonary arterial hypertension and a reversal of the initial shunt. This syndrome represents the most severe spectrum of pulmonary vascular disease associated with congenital heart defects and is characterized by hypoxemia, erythrocytosis, and systemic cyanosis. Despite advances in early diagnosis and intervention in congenital heart disease, Eisenmenger syndrome remains a significant concern due to the irreversible nature of pulmonary vascular changes and associated multisystem complications. This article provides a comprehensive review of the pathophysiology, clinical manifestations, and the role of pharmacologic and non-pharmacologic therapies, including advanced palliative care, to improve patient quality of life. Emerging therapies such as endothelin receptor antagonists, phosphodiesterase-5 inhibitors, and prostacyclin analogs show promise in symptom management, though surgical interventions, such as heart-lung transplantation, remain reserved for selected cases. Given the high mortality associated with Eisenmenger syndrome, a multidisciplinary approach is critical in managing complications, improving patient outcomes, and supporting functional status.