[Correlation between pulmonary hypertension and portal hypertension--2 case reports of different forms of pre-sinusoidal portal hypertension].

Since its first description in 1951 by Mantz and Craig pulmonary hypertension in combination with portal hypertension has been observed more and more frequently. In a recent prospective study Hadengue et al. reported an incidence of 2%. Thus this simultaneous occurrence can no longer be considered to be coincidental. The etiology remains still unclear. It is most probable that the development is due to vasoactive substances which bypass the liver or which are produced in the lung itself, and which, due to a long-term vasoconstriction, causes irreparable damage to the arterioles and arteries in the lung. Such pulmonary hypertension can develop in the presence of a pre- as well as an intrahepatic block, even when the portal hypertension is partially or completely alleviated by a portosystemic anastomosis. This last circumstance can be illustrated by two cases which were observed by our group. Case A is of particular interest because it is the first documentation of a case of an intrahepatic block due to a (so-called) macronodular transformation of the liver in the absence of portal thrombosis (a so-called NRH: nodular regenerative hyperplasia) in combination with pulmonary hypertension. This type of non-cirrhotic portal hypertension can be associated with micronodular transformation of the liver as well. Post-hepatic blocks or the so-called BUDD-CHIARI Syndrome type appear to carry no risk of development of pulmonary hypertension. It remains unclear which particular etiologies increase susceptibility to later development of pulmonary hypertension.