Vascular flow restriction devices and related systems and methods

A delivery system for a vascular flow restriction implant, comprising:

• an inner catheter with a distal end configured for insertion into a patient's vasculature and a proximal end with an inner catheter hub, the inner catheter defining at least one lumen having a side opening on the inner catheter proximally spaced from the distal end,
• a retractable outer sheath disposed over the inner catheter, said outer sheath having a distal end configured for insertion into the patient's vasculature and a proximal end with an outer sheath hub, wherein relative movement of the outer sheath hub and inner catheter hub exposes or covers the distal end of the inner catheter;
• an expandable flow restriction implant received on the distal end of the inner catheter distally with respect to said side opening and inside the outer sheath, wherein the flow restriction implant comprises a self-expanding structure with two open ends;
• and
• a recapture fiber extending from the inner catheter hub through the inner catheter lumen and out said side opening to engage the expandable flow restriction device, said recapture fiber manipulable at the inner catheter hub to control expansion or collapse of the flow restriction implant, and wherein the recapture fiber is releasable from the flow restriction implant,
• wherein the flow restriction implant comprises a drawstring around a proximal end of the flow restriction device configured to collapse said device when tensioned;
• and
• the recapture fiber comprises a looped fiber with two opposite ends lying together at a recapture fiber port in the inner catheter hub and a bight end passing through the inner catheter side opening and through the drawstring of the flow restriction implant such that pulling the two opposite ends of the recapture fiber together collapses the flow restriction device and pulling one end removes the recapture fiber.