[Pulmonary hypertension in liver diseases]

Area of Science:

• Cardiology
• Hepatology
• Pulmonology

Context:

• Portopulmonary hypertension (PoPH) is a serious condition defined by co-existing portal hypertension and precapillary pulmonary hypertension.
• PoPH shares similar pathobiological mechanisms with other forms of pulmonary arterial hypertension (PAH).
• Its prevalence ranges from 0.5-5% in patients with portal hypertension, with or without cirrhosis.

Purpose:

• To outline the diagnostic criteria and prevalence of PoPH.
• To discuss current treatment strategies and prognostic factors for PoPH.
• To explore the role of liver transplantation and emerging therapies in managing PoPH.

Summary:

• PoPH diagnosis requires elevated mean pulmonary arterial pressure (mPAP ≥ 25 mmHg), low pulmonary capillary wedge pressure (PCWP < 15 mmHg), and high pulmonary vascular resistance (PVR > 3 Wood units).
• Treatment typically follows idiopathic PAH guidelines, but must consider the severity of the underlying liver disease.
• Prognosis is influenced by both PAH severity and liver disease status. Orthotopic liver transplantation (OLT) may be contraindicated in severe cases (mPAP > 35 mmHg with RV dysfunction or high PVR).
• Bridge therapy with PAH-specific treatments can improve hemodynamics for OLT. Combining PAH therapies and OLT shows promise for stabilizing or curing PoPH in selected patients.
• Interferon (IFN) therapy is suggested as a potential risk factor for PAH.

Impact:

• Provides a comprehensive overview of PoPH, aiding clinicians in diagnosis and management.
• Highlights the complex interplay between liver and lung disease in PoPH.
• Informs therapeutic decisions, including the potential for liver transplantation and the use of specific PAH treatments.
• Suggests potential avenues for future research into PoPH pathogenesis and treatment, including the role of IFN therapy.