[A special form of double vena cava inferior].

In 231 cases the frequency of double inferior Cava in postrenal part is determined at 0.5%. The importance of double inferior Cava is discussed. This variation is the most frequent of V. cava inferior. The genesis is by persistence of left sacro-cardinal-vein (supracardinal-vein) over the six embryonical week. The casus, here mentioned, has an anastomosis overmore. This anastomosis cross Aorta and A. mesenterica inferior ventral, combines both inferior Cavae and must be interpreted as a second inferior Anastomosis intersubcardinalis.