Circulatory assist device

A medical device, comprising:

• a tubular scaffold, the scaffold including an inner surface and an outer surface;
• a flexible inner member extending along at least a portion of the inner surface of the scaffold;
• an activation assembly positioned along a portion of the inner member, the activation assembly including a conductive member having a first end region and a second end region, wherein a portion of the first end region is coupled to an activation element, and wherein the second end region is coupled to a power source;
• wherein the power source is configured to deliver an electrical stimulus to the activation element, and wherein the electrical stimulus causes the activation element to shift the inner member between a first configuration and a second expanded configuration:
• wherein the inner member includes a first attachment region, a second attachment region and a medial region extending between the first and second attachment regions, and wherein the medial region is free from attachment to the inner surface of the scaffold.

A medical stent for pumping blood, comprising:

• a tubular scaffold, the scaffold including an inner surface and a lumen extending therein;
• a flexible sleeve extending along at least a portion of the inner surface of the scaffold, wherein at least a portion of the sleeve includes an electroactive polymer;
• a first valve member;
• a second valve member;
• and
• a conductive member having a first end region and a second end region, wherein a portion of the first end region is coupled to the electroactive polymer and wherein the second end region is coupled to a power source;
• wherein the power source is configured to deliver an electrical stimulus to the electroactive polymer;
• wherein the electrical stimulus causes the electroactive polymer to shift the flexible sleeve between a narrowed configuration and an expanded configuration;
• wherein shifting the flexible sleeve from the narrowed configuration to the expanded configuration is configured to draw blood into a lumen of the flexible sleeve via the first valve member, and wherein shifting the flexible sleeve from the expanded configuration to the narrowed configuration is configured to pump blood out of the lumen of the flexible sleeve via the second valve member.