Wireless, LCR-based, passive sensor systems for implantable deployment using collapsible electromechanics and applications of same

Patent metadata

Field	Value
Publication number	US-12533228-B2
Application number	US-202118024327-A
Country	US
Kind code	B2
Filing date	Sep 7, 2021
Priority date	Sep 4, 2020
Publication date	Jan 27, 2026
Grant date	Jan 27, 2026

Abstract

Provided are systems and methods for wireless, LCR-based, passive sensor systems for catheter or other implantable deployment using collapsible electromechanics. Each sensor system includes a deformable coil and a capacitive pressure sensor, collectively forming a LCR circuit having a self-resonant frequency. Multiple sensor systems may be implanted in a collapsible artificial valve to non-invasively detect the status of the collapsible artificial valve. Specifically, when the collapsible artificial valve is implanted in a mammal subject, antennas may be disposed on the skin of the mammal subject to wirelessly measure the self-resonant frequencies of the LCR circuits of the sensor systems. Thus, the blood pressure of the mammal subject may be calculated based on the self-resonant frequencies measured by the antenna, and the status of the collapsible artificial valve may be determined based on the blood pressure.

First claim

What is claimed is:

1 . A detection system for an artificial aortic valve disposed between a left ventricle and an aorta of a mammal subject, comprising:
a plurality of wireless inductor-resistor-capacitor (LCR)-based passive sensor systems, wherein the artificial aortic valve is configured to switch between an expanded state and a crimped state according to heartbeats of the mammal subject, and each of the wireless LCR-based passive sensor systems comprises:
a deformable coil disposed on a surface of the artificial aortic valve, wherein the deformable coil forms an inductor-resistor; and
a capacitive pressure sensor disposed in the artificial aortic valve, wherein the capacitive pressure sensor comprises a plurality of sensor electrodes electrically connected to the deformable coil in parallel to form a capacitor, and the capacitive pressure sensor and the deformable coil collectively form an LCR circuit having a self-resonant frequency configured to change based on a blood pressure of the mammal subject;
wherein the wireless LCR-based passive sensor systems comprise:
a first sensor system disposed at a first side of the artificial aortic valve adjacent to the left ventricle, wherein the LCR circuit of the first sensor system has a first self-resonant frequency; and
a second sensor system disposed at a second side of the artificial aortic valve adjacent to the aorta, wherein the LCR circuit of the second sensor system has a second self-resonant frequency different from the first self-resonant frequency;
a plurality of antennas respectively disposed on a skin of the mammal subject and wirelessly in communication with the deformation coils of the first and second sensor systems correspondingly, wherein the antennas is configured to measure the self-resonant frequencies of the LCR circuits of the first and second sensor systems; and a computing device communicatively connected to the antennas, configured to:
calculate a first blood pressure of the mammal subject at the left ventricle based on the first self-resonant frequency measured by the antennas;
calculate a second blood pressure of the mammal subject at the aorta based on the second self-resonant frequency measured by the antennas; and
determine the status of the artificial aortic valve based on the first blood pressure and the second blood pressure.

2 . The detection system of claim 1 , wherein for each of the first and second sensor systems, the self-resonant frequency f of the LCR circuit is:

f
=

1

2
⁢
π
⁢

√

LC
⁡
(
p
)

,

wherein L is an inductance of the deformable coil, p is the first blood pressure or the second blood pressure, and C(p) is a capacitance function of the capacitive pressure sensor.

3 . The detection system of claim 2 , wherein for each of the first and second sensor systems, the self-resonant frequency f of the LCR circuit is in a range between 300 KHz and 50 MHz.

4 . The detection system of claim 1 , wherein each of the antennas is located within a maximum readout distance D from the artificial aortic valve.

5 . The detection system of claim 4 , wherein the maximum readout distance D is 10 cm.

6 . The detection system of claim 1 , wherein for each of the wireless LCR-based passive sensor systems, the deformable coil is a multi-turn coil comprising:
a conductive metal wire; and a plurality of sleeves partially covering the conductive metal wire, wherein each of the sleeves is more rigid than the conductive metal wire, such that when the artificial aortic valve switches to the crimped state, the deformable coil deforms at locations not covered by the sleeves.

7 . The detection system of claim 6 , wherein multi-turn coil when the artificial aortic valve switches to the crimped state, an additional thickness of the deformable coil of each of the first and second sensor systems added on the surface of the artificial aortic valve in the crimped state is less than 1 mm.

8 . The detection system of claim 6 , wherein the deformable coil of the first sensor system and the deformable coil of the second sensor system have different turns.

9 . An artificial aortic valve having the detection system of claim 1 implanted therein.

10 . A method for detecting a status of an artificial aortic valve implanted between a left ventricle and an aorta of a mammal subject, comprising:
disposing a plurality of wireless inductor-resistor-capacitor (LCR)-based passive sensor systems at different locations of the artificial aortic valve, wherein the artificial aortic valve is configured to switch between an expanded state and a crimped state according to heartbeats of the mammal subject, and each of the wireless LCR-based passive sensor systems comprises:
a deformable coil disposed on a surface of the artificial aortic valve, wherein the deformable coil forms an inductor-resistor; and
a capacitive pressure sensor disposed in the artificial aortic valve, wherein the capacitive pressure sensor comprises a plurality of sensor electrodes electrically connected to the deformable coil in parallel to form a capacitor, and the capacitive pressure sensor and the deformable coil collectively form an LCR circuit having a self-resonant frequency configured to change based on a blood pressure of the mammal subject;
wherein the wireless LCR-based passive sensor systems comprise:
a first sensor system disposed at a first side of the artificial aortic valve, wherein the LCR circuit of the first sensor system has a first self-resonant frequency; and
a second sensor system disposed at a second side of the artificial aortic valve, wherein the LCR circuit of the second sensor system has a second self-resonant frequency different from the first self-resonant frequency;
implanting the artificial aortic valve between the left ventricle and the aorta of the mammal subject, wherein the first side of the artificial aortic valve is adjacent to the left ventricle, and the second side of the artificial aortic valve is adjacent to the aorta; disposing a plurality of antennas respectively on a skin of the mammal subject, wherein the antenna are wirelessly in communication with the deformation coils of the first and second sensor systems correspondingly; measuring, by the antennas, the self-resonant frequencies of the LCR circuits of the first and second sensor systems; calculating a first blood pressure of the mammal subject at the left ventricle based on the first self-resonant frequency measured by the antennas; calculating a second blood pressure of the mammal subject at the aorta based on the second self-resonant frequency measured by the antennas; and determining the status of the artificial aortic valve based on the first blood pressure and the second blood pressure.

11 . The method of claim 10 , wherein for each of the first and second sensor systems, the self-resonant frequency f of the LCR circuit is:

f
=

1

2
⁢

Assignees

• Univ Northwestern

Inventors

• Rogers John A
• Banks Anthony R
• Lu Di

Classifications

• A61B5/6869

  Heart · CPC title

• A61B5/686

  Permanently implanted devices, e.g. pacemakers, other stimulators, biochips (A61B5/6861 takes precedence) · CPC title

• A61B5/0215

  by means inserted into the body · CPC title

• A61F2/24 Primary

  Heart valves {; Vascular valves, e.g. venous valves; Heart implants, e.g. passive devices for improving the function of the native valve or the heart muscle; Transmyocardial revascularisation [TMR] devices; Valves implantable in the body} · CPC title

• A61B5/4836

  Diagnosis combined with treatment in closed-loop systems or methods (A61B5/0036 takes precedence) · CPC title