Implantable Device Accelerometer Signals for Functional Status

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current medical device systems lack an effective method to objectively determine patient functional status, particularly in monitoring changes in well-being related to activities like the Sit-To-Stand test, which is crucial for guiding therapies and assessing health improvements or declines.

Innovation Solution

A medical device system incorporating accelerometer circuitry to generate sagittal, vertical, and transverse axis signals, and processing circuitry to calculate patient-specific functional status parameters from these signals over defined time segments, facilitating the transmission of these parameters for objective assessment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If implantable medical devices record only cardiac electrogram signals, then the device complexity is low, but the measurement precision of patient functional status is insufficient

Engineering Contradiction:
Improvepatient functional statusVSAvoiddevice complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent combines multiple sensing capabilities (accelerometer, ECG, other physiological sensors) within a single implantable medical device system. The accelerometer circuitry generates signals including sagittal axis, vertical axis, and transverse axis signals that are integrated with cardiac electrogram signals to comprehensively assess patient functional status during activities like Sit-To-Stand tests.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The implantable medical device is designed to perform multiple functions: recording cardiac electrogram signals for arrhythmia detection, capturing accelerometer-generated signals for functional status assessment, and monitoring other physiological parameters. This multi-functional approach enables the device to provide both cardiac therapy and functional status monitoring without requiring separate devices.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Measurement precision

If the medical device system uses multiple sensors to generate physiological signals, then the measurement precision improves, but the device complexity increases

Engineering Contradiction:
Improvefunctional status parameterVSAvoiddevice complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent segments the functional status assessment into distinct components: accelerometer circuitry generates specific signals (sagittal axis, vertical axis, transverse axis), processing circuitry calculates patient-specific parameters from these signals, and timestamp data defines measurement time segments. This segmentation allows for precise functional status measurement while organizing the complexity into manageable, specialized components.

Inventive Principle:
Principle #1Segmentation

3Reliability

If the system calculates patient-specific parameters from accelerometer signals, then the reliability of functional status assessment improves, but the use of energy increases

Engineering Contradiction:
Improvefunctional status assessmentVSAvoiduse of energy
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The implantable medical device autonomously calculates patient-specific functional status parameters from accelerometer-generated signals using its own processing circuitry. The device independently defines time segments using timestamp data and computes functional status without requiring external processing, thereby improving reliability while managing energy consumption through efficient onboard computation.

Inventive Principle:
Principle #25Self-service

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Provides an objective measure of patient functional status changes, helping to determine whether health is improving, declining, or stable, and can guide therapies by quantifying efforts and balance during activities like the Sit-To-Stand test.

Implementation Method 1

accelerometer circuitry configured to generate a plurality of signals including a sagittal axis signal, a vertical axis signal and a transverse axis signal

Methodology Applied
Scientific EffectAccelerometer: Accelerometer

Data Source

PatentEP3493739B1Mobile application to prompt physical action to measure physiologic response in implantable device
Publication Date: 2021.05.12 MEDTRONIC INC
  • EP3493739B1 patent drawingFigure 1
  • EP3493739B1 patent drawingFigure 2
  • EP3493739B1 patent drawingFigure 3

AI summary

A user equipment that includes a touchscreen, and at least one processor configured to generate first timestamp data based upon detection of a first touch event on the touchscreen, and second timestamp data based upon detection of a second touch event on the touchscreen, for calculation by a medical device system of a patient-specific functional status parameter associated with a Sit-To-Stand performance test over a time segment inclusively bounded by a first time defined by the first timestamp data and a second time defined by the second timestamp data.