Spontaneous reversal of portal blood flow demonstrated by percutaneous transhepatic catheterization: report of two cases.

Two patients are described in whom percutaneous transhepatic catheterization of the portal vein for a hemodynamic study demonstrated a continuous reversed blood flow in the portal vein, entering into a large collateral. The measurements made of blood pressure in the superior mesenteric, splenic, and left gastric veins, and of ammonia, immunoreactive insulin, and C-peptide in blood taken from these and peripheral veins all indicated reversed portal vein blood flow. The evidence for retrograde portal vein blood flow was obtained in only 2 of 203 patients with cirrhosis in whom portal hemodynamics were studied by the same procedure. Thus, spontaneous reversal of portal vein blood flow does occur, but very rarely.