Automatically adjusting band system

摘要

Devices and methods for forming a restriction in a patient are disclosed. In one exemplary embodiment, a restriction system is provided including an implantable restriction device, an implantable port in fluid communication with the implantable restriction device, and an implantable pump in fluid communication with the restriction device. In general, the implantable restriction device is adjustable and configured to form a restriction in a patient, and the implantable port is configured to receive fluid from a fluid source external to the patient. The implantable pump has a plurality of actuators configured to change shape upon the application of energy thereto such that sequential activation of the plurality of actuators is effective to create pumping action to move fluid through the pump.