Patent attributes
Apparatus and methods are described including inserting an implantable device (20) into a blood vessel of a subject while the implantable device is disposed inside a delivery device and is constrained in a constrained configuration by the delivery device. The implantable device is released from the delivery device into the blood vessel, thereby causing the implantable device to assume a non-constrained configuration by an upstream end of the implantable device radially expanding (120), a central portion (122) of the implantable device radially expanding such that along the central portion of the implantable device the inner surface (24) of the implantable device defines a diverging portion (25) of a conduit (26), and the implantable device forming a folded portion (128) between the upstream end of the implantable device and the central portion of the implantable device. Other applications are also described.