Electrophysiology Filter Circuit for Ablation Signal Isolation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Electrophysiology systems face challenges in maintaining signal fidelity and protecting equipment from unintended signal diversion and leakage, particularly during procedures involving high-frequency ablation signals and electrogram signals, which can divert through unintended paths and damage equipment.

Innovation Solution

A filtering circuit is introduced within the electrophysiology system, featuring parallel channels with LC traps tuned to specific frequencies to present high impedance to ablation and navigation signals, preventing diversion through the electrogram signal path, and allowing low impedance for pacing signals, thus maintaining signal integrity and protecting equipment.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If high-frequency ablation signals are transmitted through the electrophysiology system, then ablation therapy can be delivered to target tissue, but the signals may divert through unintended paths and damage equipment

Engineering Contradiction:
Improveablation signal powerVSAvoidsignal diversion and equipment damage
Core Design Contradiction:
PowerVSObject-affected harmful factors

Solution Approach 1:

A filtering circuit is introduced as an intermediary component between the ablation signal source and the electrogram recording path. This filter acts as a mediator that allows the ablation signal to pass through to the tissue while blocking its diversion into the electrogram amplifier, preventing equipment damage without compromising ablation efficacy

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The filtering circuit is designed with frequency-selective parameters that change the impedance characteristics at different frequencies. At ablation frequencies, the filter presents low impedance to allow signal transmission, while at electrogram frequencies, it presents high impedance to prevent signal diversion and protect equipment

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If the electrophysiology system monitors electrogram signals for diagnostic purposes, then cardiac electrical activity can be recorded, but high-frequency ablation signals may contaminate the electrogram path and degrade signal fidelity

Engineering Contradiction:
Improveelectrogram signal fidelityVSAvoidsignal contamination from ablation
Core Design Contradiction:
Measurement precisionVSObject-generated harmful factors

Solution Approach 1:

The filtering circuit serves as an intermediary that separates the ablation signal path from the electrogram recording path. It allows diagnostic electrogram signals to be recorded with high fidelity while preventing contamination from high-frequency ablation signals through its frequency-selective blocking characteristics

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The filter's impedance parameters are designed to change with frequency, presenting high impedance to ablation-frequency signals to prevent contamination of the electrogram path, while maintaining low impedance for diagnostic electrogram frequencies to ensure accurate signal recording

Inventive Principle:
Principle #35Parameter changes

3Ease of operation

If the system allows pacing signals to pass through for cardiac stimulation, then cardiac rhythm can be controlled, but ablation signals may also pass through and cause unintended tissue heating

Engineering Contradiction:
Improvepacing signal transmissionVSAvoidunintended tissue heating from ablation signal leakage
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The filtering circuit employs frequency-dependent impedance parameters that allow low-frequency pacing signals to pass through with minimal attenuation for effective cardiac stimulation, while presenting low impedance at ablation frequencies to safely conduct high-power ablation signals to the tissue without causing unintended heating from signal leakage

Inventive Principle:
Principle #35Parameter changes

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

The filtering circuit effectively minimizes signal diversion, enhances signal fidelity, and protects equipment by isolating high-frequency ablation signals from the electrogram path, while allowing pacing signals to pass through, resulting in more accurate position determinations and safer procedures.

Implementation Method 1

A filtering circuit is introduced within the electrophysiology system, featuring parallel channels with LC traps tuned to specific frequencies to present high impedance to ablation and navigation signals

Methodology Applied
Scientific EffectInductance: Inductor

Implementation Method 2

A filtering circuit is introduced within the electrophysiology system, featuring parallel channels with LC traps tuned to specific frequencies to present high impedance to ablation and navigation signals

Methodology Applied
Scientific EffectCapacitance: Capacitance

Implementation Method 3

A filtering circuit is introduced within the electrophysiology system, featuring parallel channels with LC traps tuned to specific frequencies to present high impedance to ablation and navigation signals, preventing diversion through the electrogram signal path, and allowing low impedance for pacing signals

Methodology Applied
Scientific EffectElectrical Impedance: Electrical Resistance

Data Source

PatentEP3190961B1Ablation generator comprising filter circuit for electrophysiology system
Publication Date: 2019.11.13 ST JUDE MEDICAL CARDILOGY DIV INC
  • EP3190961B1 patent drawingFigure 1
  • EP3190961B1 patent drawingFigure 2~3
  • EP3190961B1 patent drawingFigure 4~5

AI summary

An ablation generator may include an input port for receiving a monitoring signal respective of tissue of the patient and an output port for providing the monitoring signal another device. A filtering circuit may be disposed between the input port and the output port, the filtering circuit configured to present a high impedance at one or more frequencies at or near which a mapping and navigation system associated with the ablation generator transmits a signal. The filtering circuit may additionally or alternatively be provided in a monitoring system or another component in an electrophysiology system.