Apparatus for noninvasive measurement of a heart performance metric

Patent metadata

Field	Value
Publication number	US-11540734-B2
Application number	US-201916551362-A
Country	US
Kind code	B2
Filing date	Aug 26, 2019
Priority date	Aug 27, 2018
Publication date	Jan 3, 2023
Grant date	Jan 3, 2023

Abstract

An apparatus for measuring a performance metric of a heart includes a housing, a tactile sensor, a finger clamp, a linear actuator, and a controller. The tactile sensor measures blood pressure pulsatility in a digital artery of a finger via applanation tonometry and outputs pulsatility signals indicative of the blood pressure pulsatility. The finger clamp extends from the housing to clamp the finger against the tactile sensor with the digital artery aligned over the tactile sensor. The linear actuator drives the finger clamp with a clamping force directed along a linear path. The controller is coupled to the tactile sensor and the linear actuator to control the clamping force and to generate pulsatility data, based upon the pulsatility signals, from which the performance metric of the heart may be determined.

First claim

What is claimed is:

1. An apparatus for measuring a performance metric of a heart, the apparatus comprising:
a housing;
a tactile sensor adapted to measure blood pressure pulsatility in a digital artery of a finger via applanation tonometry and output pulsatility signals indicative of the blood pressure pulsatility, wherein the tactile sensor is disposed on a flat surface that protrudes from the housing at an oblique angle from an outer surface of the housing;
a finger clamp including an adjustable jaw extending from an opening in the housing and configured to move along a linear path to clamp the finger against the tactile sensor with the digital artery aligned over the tactile sensor;
a linear actuator configured to drive the adjustable jaw along the linear path to apply a clamping force; and
a controller coupled to the tactile sensor and the linear actuator and adapted to control the clamping force and to generate pulsatility data, based upon the pulsatility signals, from which the performance metric of the heart may be determined.

2. The apparatus of claim 1 , wherein the housing has a size and a shape which allows for the housing to be grasped by a hand.

3. The apparatus of claim 2 , wherein the finger clamp is positioned and oriented on the housing to clamp an index finger while the housing is grasped by the hand and the tactile sensor is positioned and oriented to measure the blood pressure pulsatility from an ulnar side digital artery of the index finger.

4. The apparatus of claim 3 , further comprising:
a user interface disposed on a side of the housing and positioned to be reachable by a thumb of the hand while the index finger is clamped in the finger clamp, the user interface coupled to the controller to enable a user to start or stop a measurement of the performance metric of the heart.

5. The apparatus of claim 2 , further comprising one or more of:
one or more alignment shims extending from the housing and configured to adjust a rotational position of a palm of the hand relative to the finger clamp while the hand is grasping the housing;
a finger web stop extending from the housing and positioned to be cradled by a finger web of the finger is positioned in the finger clamp, wherein the finger web stop is adjustable to alter an axial position of the finger relative to the finger clamp;
a fingertip stop extending from the housing and positioned to abut against a tip of the finger when the finger is positioned in the finger clamp, wherein the fingertip stop is adjustable to alter the axial position of the finger relative to the finger clamp; or
a finger holster extending from the housing and positioned on the housing to locate and secure a portion of the finger that extends past the finger clamp.

6. The apparatus of claim 2 , wherein the housing is shaped to rest on a tabletop while enabling the hand to grasp the housing while an arm connected to the hand is also resting on the tabletop during measurement of the performance metric of the heart.

7. The apparatus of claim 1 , wherein the finger clamp has a curved shape configured to cradle a side of the finger located opposite the tactile sensor when the finger is positioned in the finger clamp.

8. The apparatus of claim 7 , wherein the controller includes logic that when executed by the controller causes the apparatus to perform operations including:
clamping the finger to a sufficient enough pressure to measure the blood pressure pulsatility in the digital artery via applanation tonometry while not fully occluding the digital artery or an opposing digital artery of the finger.

9. The apparatus of claim 1 , wherein the linear actuator comprises:
a motor disposed with the housing to generate a rotational force;
a leadscrew coupled to an output of the motor to translate the rotational force to the clamping force directed along the linear path, wherein the leadscrew extends into and engages with the adjustable jaw of the finger clamp.

10. The apparatus of claim 9 , wherein the finger clamp further comprises:
a manual release knob extending from the adjustable jaw of the finger clamp, wherein the manual release knob engages with the leadscrew and provides a manual release of the clamping force when turned, pressed, or pulled.

11. The apparatus of claim 1 , wherein the apparatus is adapted to measure a left ventricular end diastolic pressure (LVEDP) and wherein the apparatus further comprises:
a mouthpiece shaped to receive an expiration of a user;
an air tube connecting the mouthpiece to the housing; and
a pressure sensor disposed within the housing and coupled to the air tube to measure an air pressure of the expiration, wherein the controller is coupled to the pressure sensor and adapted to monitor the air pressure while generating the pulsatility data.

12. The apparatus of claim 1 , wherein the tactile sensor comprises a two dimension capacitive sensor array having more rows than columns, wherein the rows align parallelly to a longitudinal axis of the finger when the finger is clamped in the finger clamp.

13. The apparatus of claim 1 , further comprising:
a wireless communication interface disposed within the housing and coupled to the controller, wherein the controller is adapted to wirelessly communicate with a remote device to provide a graphical user interface for orchestrating a test of the performance metric of the heart and displaying results of the test, wherein the graphical user interface includes:
an expiratory effort meter for displaying when a user is exerting appropriate expiratory effort; and
a pulsatility meter for displaying when the blood pressure pulsatility is being sensed by the tactile sensor.

14. The apparatus of claim 1 , wherein the tactile sensor is mounted to the housing and wherein the linear actuator and the controller are disposed at least partially within the housing.

15. At least one non-transitory machine-accessible storage medium that provides instructions that, when executed by a system, will cause the system to perform operations comprising:
linearly actuating an adjustable jaw of a finger clamp along a linear path to apply a clamping force to a finger to flatten a digital artery for applanation tonometry, wherein the adjustable jaw moves linearly in and out of an opening in a housing from which the finger clamp extends to clamp the finger externally to the housing while a hand including the finger grasps an exterior of the housing;
monitoring pulsatility signals output from a tactile sensor disposed in or on an inward-facing surface of the finger clamp; and
generating pulsatility data, based upon the pulsatility signals, from which a performance metric of the heart may be determined.

16. The at least one non-transitory machine-accessible storage medium of claim 15 , further providing instructions that, when executed by the system, will cause the system to perform further operations, comprising:
monitoring an expiratory effort while monitoring the pulsatility signals;
recording the pulsatility data while the expiratory effort is within a threshold range; and
recording the pulsatility data following cessation of the expiratory effort.

17. The at least one non-transitory machine-accessible storage medium of claim 16 , further providing instructions that, when executed by the system, will cause the system to perform further operations, comprising:
analyzing the pulsatility data recorded during the expiratory effort and recorded following the expiratory effort to determine the performance metric, wherein the performance metric comprises a left ventricul

Assignees

• Verily Life Sciences Llc

Inventors

• Debusschere Derek
• Yaffe Benjamin K
• Fong Shannon

Classifications

• A61B5/02416 Primary

  using photoplethysmograph signals, e.g. generated by infrared radiation (A61B5/14552 takes precedence) · CPC title

• A61B5/02225

  using the oscillometric method · CPC title

• A61B5/02116

  of pulse wave amplitude (A61B5/02225 takes precedence) · CPC title

• A61B5/087

  Measuring breath flow · CPC title

• A61B5/0205

  Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition · CPC title