A catheter having a shaft with a substantially circular profile and a catheter channel on the inner wall spiraling about the catheter longitudinal axis. In some embodiments, the catheter has multiple catheter channels spiraling about the catheter longitudinal axis. Certain embodiments include the catheter as part of a system, including an implantable port system with a rifled port outlet stem, and an infusion system with a rifled syringe distal component.
