Abstract: A cryoablation system includes a catheter for insertion into patient vasculature. The catheter includes a coolant transfer tube configured to receive and transfer coolant from a coolant source to an expansion element coupled to a distal portion of the catheter. The expansion element is in fluid communication with the coolant transfer tube and at least one coolant outtake region within the catheter. The coolant outtake region is configured and arranged to receive and transfer coolant from the expansion element to a reduced pressure region. A coolant-flow regulation system is at least partially disposed in the catheter. The coolant-flow regulation system is configured and arranged for regulating a rate of coolant flow within the cryoablation system by providing an adjustable pressure differential along the at least one coolant outtake region. A control module is coupled to the catheter. The control module includes a processor for controlling the coolant-flow regulation system.