Abstract: A stent is placed inside an aorta of a subject, the stent comprising one or more electrodes, control circuitry, and a first antenna coupled thereto. A second antenna circumscribes a neck of the subject, such that that at least one turn of wire of the second antenna extends from a first position that is anatomically superior to a left clavicle of the subject to a second position that is anatomically inferior to a jugular notch of the subject and from the second position to a third position that is anatomically superior to a right clavicle of the subject. The second antenna transmits an electrical signal to the first antenna via inductive coupling, and is shaped to have an L-shaped projection in a sagittal plane, with an angle between two legs of the L-shaped projection being 80-160 degrees when placed upon a flat surface. Other applications are also described.

Abstract: Apparatus and methods are described for use with a blood vessel of a subject. An annular antenna is placed inside the blood vessel such that radial expansion of the antenna is limited by a circumference of the blood vessel. A transmitter generates an inductive current in the antenna, by transmitting RF energy toward the antenna. A control unit measures the inductive current in the antenna, and, in response thereto, determines a physiological parameter of the subject. Other applications are also described.

Abstract: Apparatus and methods are described including a stent (20) configured to be placed inside an aorta of a subject, the stent comprising one or more electrodes (22), control circuitry (32), and a first antenna (28) coupled thereto. A second antenna (26) is placed on the subject, such that the second antenna extends at least from above a left clavicle of the subject to below a jugular notch of the subject and from below the subject's jugular notch to above a right clavicle of the subject, the second antenna being con figured to transmit an electrical signal to the first antenna via inductive coupling. Other applications are also described.

Abstract: Apparatus and methods are described for use with a blood vessel of a subject. An annular antenna is placed inside the blood vessel such that radial expansion of the antenna is limited by a circumference of the blood vessel. A transmitter generates an inductive current in the antenna, by transmitting RF energy toward the antenna. A control unit measures the inductive current in the antenna, and, in response thereto, determines a physiological parameter of the subject. Other applications are also described.

Abstract: Apparatus and methods are provided for use with a blood vessel of a subject, including a stent (20) configured to be placed in the blood vessel. The stent includes at least first (32), second (34), and third (36) strut portions disposed along the stent. The first and second strut portions are coupled to one another at a first junction (37A) that facilitates bending of the first and second strut portions with respect to one another. The second and third strut portions are coupled to one another at a second junction (37B) that facilitates bending of the second and third strut portions with respect to one another. At least one electrode (22) is disposed on at least an outer surface of the stent. Other applications are also described.

Abstract: Apparatus and methods are provided for use with a blood vessel of a subject, including a stent (20) configured to be placed in the blood vessel. The stent includes at least first (32), second (34), and third (36) strut portions disposed along the stent. The first and second strut portions are coupled to one another at a first junction (37A) that facilitates bending of the first and second strut portions with respect to one another. The second and third strut portions are coupled to one another at a second junction (37B) that facilitates bending of the second and third strut portions with respect to one another. At least one electrode (22) is disposed on at least an outer surface of the stent. Other applications are also described.