A useful update: Liver Transpl 2012; 18: 881-91.
Definition: When pulmonary artery hypertension (PAH), mean pulmonary artery pressure (MPAP) ≥ 25 mm Hg, occurs in the setting of of portal hypertension and no alternative cause of the PAH exists (eg, collagen vascular disease, congenital heart disease, or certain drugs), it is known as portopulmonary hypertension (POPH).
- Mild POPH: MPAP < 35 mm Hg
- Moderate POPH: MPAP ≥ 35 mm Hg & <45 mm Hg
- Severe POPH: MPAP ≥ 45 mm Hg
Patients with moderate POPH and severe POPH, if not improved with medical therapy, have high mortality rates and these are generally considered contraindications for liver transplantation.
POPH is associated with high pulmonary vascular resistance ≥ 240 dyn(sec)(cm¯5 ) and with pulmonary wedge pressure < 15 mm Hg.
Difference between POPH and hepatopulmonary syndrome:
From the following link: Portopulmonary hypertension and hepatopulmonary syndrome “Abnormal intrapulmonary vascular dilatation, the hallmark of hepatopulmonary syndrome, can cause profound hypoxaemia that can be very difficult to treat. By contrast, portopulmonary hypertension results from excessive pulmonary vasoconstriction and vascular remodelling that eventually leads to right-heart failure.”
Pathophysiology: unclear. Most but not all cases are associated with cirrhosis.
Frequency: 6-8% of cirrhotic patients.
Diagnosis: while dyspnea may be present, routine screening with echocardiography is part of liver transplantation evaluation.
Prognosis: retrospective study from Mayo clinic (n=74, 1994-2007) noted 5-hr survival of 14% for untreated patients, 45% treated with vasodilators, and 67% who underwent liver transplantation.
Treatments: Table 6 in article.
- PDE5 Inhibitors (oral): Tadalfil, Sildenafil
- Endothelin Receptor antagonists (oral): Ambrisentan, Bosentan
- Prostacyclins (IV): EPO, Trepostinil
- Prostacyclins (Inhalation): Iloprost , Tyvaso
- Liver transplantation: 79 patients with LT for POPH 2007-2011
Beta-blockers may have adverse effect.
Noncirrhotic POPH: Worldwide, infection with Schistosoma mansion is likely the most common reason; severe disease may occur in 10% of the 200 million people who are infected. When noncirrhotic POPH occurs without cirrhosis or Schistosoma mansion, this requires a high degree of clinical suspicion as well as awareness of this disorder.
**Hepatology 2008; 48: 13, 196. POPH: pulmonary arterial htn associated w portal htn:
- -resting pulm artery pressure > 25mmHg
- -pulm capillary wedge pressure <15mmHg
- -pulm vascular resistance >240dynes(s)(cm to -5)
- -measure c trans thoracic echocardiography
- -female sex, autoimmune dz were risk factors
- -avg age associated was 53yrs whereas idiopathic PAH avg age is 36yrs
**NEJM 2008; 358: 2378. Review. Hepatopulmonary Syndrome – New England Journal of Medicine Hepatopulmonary syndrome, a separate but related condition characterized by hypoxemic respiratory insufficiency due to increased intrapulmonary shunting
**Liver Tx 2007; 13: 680. Hepatopulmonary syndrome experience at CHOA