Self-established porto-caval and porto-pulmonary shunts in mechanically induced portal hypertension. An experimental study.

Portal hypertension was mechanically induced in rats by partial constriction of the portal vein. Angiography revealed the spontaneous development of porto-systemic and porto-pulmonary shunts in all hypertensive animals. A coincident decompression of the portal system was recorded. Release of the portal vein constriction led to disappearance of the collaterals in most of the experimental animals.