Often confused as the same syndrome, Hepatopulmonary syndrome and Portopulmonary hypertension are two distinct disease processes. Both are characterized as pulmonary vascular abnormalities in the context of liver disease.
Hepatopulmonary Syndrome (HPS): triad of vasodilatation (Intrapulmonary vascular dilatations), abnormal oxygenation (an elevated alveolar-arterial oxygen gradient) and liver disease (any degree of liver disease). *LOOK FOR: digital clubbing, cyanosis and spider angiomas.
Portopulmonary hypertension (POPH): vascular obstruction secondary to portal hypertension (varices, splenomegaly, thrombocytopenia, portal vein abnormalities) with concomitant pulmonary arterial hypertension (mean pulmonary artery pressure >25 mmHg at rest, mean pulmonary capillary wedge pressure <15 mmHg, and pulmonary vascular resistance (PVR) >3 Wood units.
REFERENCES:
1. Porres-Aguilar M, Altamirano JT, Torre-Delgadillo A, Charlton MR, Duarte-Rojo A. Portopulmonary hypertension and hepatopulmonary syndrome: a clinician-oriented overview. Eur Respir Rev. 2012 Sep 1;21(125):223-33. doi: 10.1183/09059180.00007211.
2. Gupta S, Krowka M J. Hepatopulmonary syndrome. CMAJ Feb 2018, 190 (8) E223; DOI: 10.1503/cmaj.170253