Annular antenna

• US 10,828,181 B2
• Filed: 11/17/2016
• Issued: 11/10/2020
• Est. Priority Date: 09/09/2011
• Status: Active Grant

• Current Assignee: Enopace Biomedical Ltd.
• Original Assignee: Enopace Biomedical Ltd.
• Inventors: Dagan, Amir, Hanani, Nitai, Ariav, Gal, Gindin, Igor, Gross, Yossi
• Primary Examiner(s): Preston, Rebecca S
• Application Number:
  US15/354,313
• Publication Number:
  US 20170065824A1
• Time in Patent Office: 1,454 Days
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/0816 Measuring devices for examining respiratory frequency measuring frequency of electric signals G01R23/00
• CPC Class Codes: A61B 5/24 Detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2/848 having means for fixation to the vessel wall, e.g. barbs
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2002/825 having longitudinal struts
• CPC Class Codes: A61F 2002/8483 Barbs
• CPC Class Codes: A61F 2002/91541 Adjacent bands are arranged out of phase
• CPC Class Codes: A61F 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2002/91575 connected peak to trough
• CPC Class Codes: A61F 2210/0014 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2220/0016 with sharp anchoring protrusions, e.g. barbs, pins, spikes
• CPC Class Codes: A61F 2220/005 using adhesives
• CPC Class Codes: A61F 2220/0075 sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2230/0054 V-shaped
• CPC Class Codes: A61F 2250/0001 Means for transferring electromagnetic energy to implants
• CPC Class Codes: A61F 2250/0002 for data transfer
• CPC Class Codes: A61F 2250/0018 differing in elasticity, stiffness or compressibility
• CPC Class Codes: A61F 2250/0037 differing in height or in length
• CPC Class Codes: A61F 2250/008 : Alarm means
• CPC Class Codes: A61F 2250/0096 : Markers and sensors for detecting a position or changes of a position of an implant, e.g. RF sensors, ultrasound markers
• CPC Class Codes: A61N 1/05 : for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: A61N 1/0514 : Electrodes for the urinary tract
• CPC Class Codes: A61N 1/0558 : Anchoring or fixation means therefor
• CPC Class Codes: A61N 1/056 : Transvascular endocardial electrode systems
• CPC Class Codes: A61N 1/057 : Anchoring means; Means for fixing the head inside the heart
• CPC Class Codes: A61N 1/36053 : adapted for vagal stimulation A61N1/36114 takes precedence
• CPC Class Codes: A61N 1/3756 : Casings with electrodes thereon, e.g. leadless stimulators
• CPC Class Codes: A61N 1/40 : Applying electric fields by inductive or capacitive coupling microwave apparatus A61N5/00; Applying radio-frequency signals
• CPC Class Codes: A61N 2001/0585 : Coronary sinus electrodes

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.

Claims

1. Apparatus for use with a blood vessel of a subject, comprising:

an annular antenna configured to be placed inside the blood vessel such that radial expansion of the antenna is limited by a circumference of the blood vessel;

a transmitter configured to generate an inductive current in the antenna, by transmitting RF energy toward the antenna;

a control capsule comprising circuitry configured to measure the inductive current in the antenna, and, in response thereto, to determine blood pressure of the subject; and

a tubular endovascular aortic stent having an outer diameter of 10-35 mm, wherein the antenna is coupled to the tubular endovascular aortic stent and the tubular endovascular aortic stent is configured to be disposed within the subject'"'"'s body at an aortic site that is between the bifurcation of the aorta with the left subclavian artery and the bifurcation of the aorta with the fifth intercostal artery.

2. The apparatus according to claim 1, wherein the control capsule is configured to determine the blood pressure of the subject by interpreting variations in the inductive current that are measured at the antenna as being caused by variations in geometry of the antenna over the course of the subject'"'"'s cardiac cycle.

3. The apparatus according to claim 1, wherein the transmitter is configured to transmit the RF energy at a frequency of 50 kHz-100 MHz.

4. The apparatus according to claim 3, wherein the transmitter is configured to transmit the RF energy at a frequency of 90 kHz-60 MHz.

5. The apparatus according to claim 3, wherein the transmitter is configured to transmit the RF energy at a frequency of more than 60 MHz.

6. The apparatus according to claim 1, wherein a length of the stent is 30-100 mm.

7. The apparatus according to claim 1, wherein the stent has a crimped profile of 10-18 Fr.

8. The apparatus according to claim 1, wherein the stent has a crimped profile of 8-18 Fr.

9. A method comprising:

generating an inductive current, in an annular antenna that has been placed in an aorta of a subject and allowed to expand radially, such that radial expansion of the antenna is limited by a circumference of the aorta, by transmitting RF energy toward the antenna;

measuring the inductive current in the antenna; and

in response thereto, determining blood pressure of the subject,

the method being performed using an apparatus comprising;

the annular antenna;

a transmitter which will generate the inductive current in the antenna, by transmitting the RF energy toward the antenna;

a control capsule comprising circuitry which will measure the inductive current in the antenna, and, in response thereto, to determine the blood pressure of the subject; and

a tubular endovascular aortic stent having an outer diameter of 10-35 mm, wherein the antenna is coupled to the tubular endovascular aortic stent and the tubular endovascular aortic stent is disposed within the subject'"'"'s body at an aortic site that is between the bifurcation of the aorta with the left subclavian artery and the bifurcation of the aorta with the fifth intercostal artery.

10. The method according to claim 9, wherein determining the blood pressure comprises interpreting variations in the inductive current that are measured at the antenna as being caused by variations in geometry of the antenna over the course of the subject'"'"'s cardiac cycle.

11. The method according to claim 9, wherein transmitting the RF energy comprises transmitting the RF energy at a frequency of 50 kHz-100 MHz.

12. The method according to claim 11, wherein transmitting the RF energy comprises transmitting the RF energy at a frequency of 90 kHz-60 MHz.

13. The method according to claim 11, wherein transmitting the RF energy comprises transmitting the RF energy at a frequency of less than 60 MHz.

14. The method according to claim 9, wherein a length of the stent is 30-100 mm.

15. The method according to claim 9, wherein the stent has a crimped profile of 10-18 Fr.

16. The method according to claim 9, wherein the stent has a crimped profile of 8-18 Fr.