Eisenmenger Syndrome: A Multisystem Disorder-Do Not Destabilize the Balanced but Fragile Physiology.

Eisenmenger syndrome is the most severe and extreme phenotype of pulmonary arterial hypertension associated with congenital heart disease. A large nonrestrictive systemic left-to-right shunt triggers the development of pulmonary vascular disease, progressive pulmonary arterial hypertension, and increasing pulmonary vascular resistance at the systemic level, which ultimately results in shunt reversal. Herein, we review the changing epidemiological patterns and pathophysiology of Eisenmenger syndrome. Multiorgan disease is an integral manifestation of Eisenmenger syndrome and includes involvement of the cardiac, hematological, neurological, respiratory, gastrointestinal, urinary, immunological, musculoskeletal, and endocrinological systems. Standardized practical guidelines for the assessment, management, risk stratification, and follow-up of this very fragile and vulnerable population are discussed. Multidisciplinary care is the best clinical practice. An approach to the prevention and management of a broad spectrum of complications is provided. Relevant therapeutic questions are discussed, including anticoagulation, noncardiac surgery, physical activity, transplantation, and advanced-care planning (palliative care). Advanced pulmonary arterial hypertension therapies are indicated in patients with Eisenmenger syndrome and World Health Organization functional class II or higher symptoms to improve functional capacity, quality of life, and-less well documented-survival. Specific recommendations regarding monotherapy or combination therapy are provided according to functional class and clinical response. The ultimate challenge for all care providers remains early detection and management of intracardiac and extracardiac shunts, considering that Eisenmenger syndrome is a preventable condition.