Table 1.

Distinctions between HPS and POPH

Characteristics	HPS	POPH
Clinical issue*	Arterial hypoxemia caused by IPVD	Pulmonary artery hypertension
Diagnostic criteria†	PaO2 < 80 mm Hg	mPAP > 25 mm Hg; PVR > 3 wood units
LD	Usually cirrhosis	Always portal hypertension
Severity	Poor correlation with LD	Poor correlation with LD
Frequency seen	5%‐32%	5%‐10%
Medical treatments‡	Wear supplemental oxygen	PV medications
5‐Year survival rate	23% (no treatments)	4%‐14%; 40% survival rate with PV therapy only
LT§	An “indication”	A “contraindication” if mPAP > 45 mm Hg
Treatment outcomes‖	Complete resolution with LT	Unpredictable, 50% resolution with LT

^*IPVDs were determined by contrast‐enhanced transthoracic echocardiography.

^†PaO₂ determined by arterial blood gas in the sitting position breathing room air; right heart catheterization measures/calculates mPAP and PVR, respectively.

^‡Several available for POPH, but only one randomized, placebo‐controlled trial conducted; no controlled trials in HPS to date.

^§Increased LT risk. Expedited LT consideration if pretransplant PaO₂ < 60 mm Hg (HPS); if mPAP < 35 mm Hg with PV therapy (POPH).

^‖Time resolution of HPS related to severity of hypoxemia; PV therapy in POPH can be discontinued in 50% after LT.