Atrial Fibrillation Detection via Beat Window Probability Analysis

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for detecting atrial fibrillation are inadequate as they often require continuous monitoring and may fail to accurately differentiate between atrial fibrillation and other cardiac arrhythmias, leading to false detections and missed diagnoses.

Innovation Solution

A cardiac rhythm monitoring device with electrodes and a processor that senses cardiac electrical activity, determines the probability of atrial fibrillation based on irregularity and R-R interval variances, and combines these probabilities to detect sudden onset of irregularity, confirming atrial fibrillation onset and termination using Markov-Chain and variance-based algorithms.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If continuous cardiac electrical activity monitoring is used to detect atrial fibrillation, then detection sensitivity is improved, but device complexity and energy consumption increase

Engineering Contradiction:
Improvedetection sensitivityVSAvoidmonitoring system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The monitoring system is segmented into multiple independent detection modules: R-R interval variance analysis module, irregularity detection module, and probability calculation module. Each module processes specific features independently and combines results, reducing overall system complexity while maintaining high detection sensitivity through distributed functionality.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system performs preliminary analysis of R-R intervals by calculating variances and detecting irregularities before making final AF detection. This preliminary processing filters out obvious non-AF cases early, reducing the computational burden on subsequent detection stages and lowering overall device complexity.

Inventive Principle:
Principle #10Preliminary action

2Measurement precision

If multiple probability calculation methods are combined to reduce false positives, then detection accuracy is improved, but processing time increases

Engineering Contradiction:
Improvedetection accuracyVSAvoidprocessing time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The system implements a tiered probability calculation approach where not all detection methods are applied equally to all cases. Routine monitoring uses simplified probability calculations, while ambiguous cases trigger more comprehensive multi-method analysis. This partial application of excessive action reduces average processing time while maintaining high accuracy for critical detections.

Inventive Principle:
Principle #16Partial or excessive action

Solution Approach 2:

The system performs probability calculations at periodic intervals rather than continuously, updating AF probability assessments at defined beat windows. This periodic processing reduces computational load and processing time while maintaining detection accuracy through regular reassessment at clinically relevant intervals.

Inventive Principle:
Principle #19Periodic action

3Reliability

If continuous monitoring is implemented to capture infrequent AF symptoms, then detection reliability is improved, but energy consumption increases

Engineering Contradiction:
Improvedetection reliabilityVSAvoidenergy consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The monitoring system operates in periodic cycles, continuously analyzing R-R intervals at defined beat windows rather than processing every cardiac cycle at full computational depth. This periodic action maintains detection reliability by regularly sampling cardiac activity while significantly reducing energy consumption through interval-based processing.

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The system uses disposable or low-cost computational algorithms that process data in small, discrete beat windows rather than maintaining complex continuous analysis state. Each beat window is processed independently with simplified probability calculations, reducing cumulative energy consumption while maintaining reliable detection over extended monitoring periods.

Inventive Principle:
Principle #27Cheap short-living objects (Disposable)

Data Source

PatentUS8121675B2Device and method for detecting atrial fibrillation
Publication Date: 2012.02.21 PACESETTER INC
  • US8121675B2 patent drawing
  • US8121675B2 patent drawing
  • US8121675B2 patent drawing

AI summary

Detection of atrial fibrillation involves detecting a plurality of ventricular events and obtaining a series of probabilities of AF, each corresponding to a probability of AF for a different beat window having a plurality of ventricular events. AF onset is detected when one or each of a plurality of consecutive AF probabilities satisfies an AF trigger threshold. AF termination is detected when one or each of a plurality of consecutive AF probabilities does not satisfy the AF trigger threshold. Upon detection of AF onset, ventricular events are processed to detect for a sudden onset of irregularity of the ventricular events. AF onset is confirmed when sudden onset is detected and overturned when sudden onset is not detected.