An extracorporeal blood treatment system including: a blood circuit having a first blood passage coupled at a first end to a first end of a blood treatment device and a second blood passage coupled at a first end to a second end of the treatment device, wherein the first and second blood passages each have a second end adapted to be coupled to a vascular system of a human patient; a first blood pump connectable to the first blood passage and a second blood pump connectable to the second blood passage, wherein said first and second blood pumps are adapted to move blood through the first and second blood passages in a first direction and in a reverse direction, and a pump controller operatively connected to the first and second blood pumps, said controller operates the blood pumps to cyclically move blood through the first and second blood passages in the first direction and the reverse direction.