Abstract: An inflatable circulation assist device is disclosed consisting of an inflatable stator housing an impeller with inflatable blades of varying shapes and sizes. The invention is introduced into the patient percutaneously. The circulation assist device is a small pump packaged into a compact form that is attached to a long flexible driveshaft. The pump is inserted along a guidewire to a target location, and then the pump is inflated. The circulation assist device's exterior is designed to expand only so much as to closely fit whatever cardiovascular system element in which it is placed for operation. The vascular assist device can be expanded either by inflation with a fluid. The driveshaft, which connects to the circulation assist device's impeller and extends outside the patient's body, is rotated by an external motor. After the circulation assist device is no longer needed, it is collapsed into a compact form and removed from the patient percutaneously.