Abstract: A connector for connecting a blood processing device to vascular tissue includes a vascular tissue connecting element that is suturable to a portion of the cardiovascular system for providing a flow connection. A junction ring is affixed to the vascular tissue connecting portion in order to form a substantially shape retaining connecting element. A locking ring for locking the junction ring to a blood processing device includes a coupling element configured to engage a port on the blood processing device so that rotation of the locking ring draws the junction ring to the port and locks the junction ring into a sealing relationship with the port. The locking ring is freely rotatable about the junction ring so that the locking ring can be rotated to lock the junction ring to the port without twisting the vascular tissue connecting element.