Implantable Device Short Circuit Detection via Electrogram Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing implantable medical devices (IMDs) face challenges in detecting short circuit conditions of medical electrical leads, which can occur intermittently and may not be detected by scheduled lead impedance measurements, potentially leading to inadequate therapy delivery during life-threatening conditions like ventricular fibrillation.
Innovation Solution
An IMD system with a controller that analyzes cardiac electrical signals, such as intracardiac electrograms, to detect short circuit conditions by identifying characteristic noise waveforms and abnormalities, allowing for real-time monitoring and alert generation to prevent therapy delivery failures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If scheduled lead impedance measurements are used to detect short circuit conditions, then the device structure remains simple, but short circuit events may go undetected due to intermittent nature of the faults
Solution Approach 1:
The patent implements continuous monitoring of cardiac electrical signals through electrograms, replacing intermittent scheduled impedance measurements. The controller continuously analyzes EGM signals for short circuit indicators, ensuring no intermittent faults are missed while maintaining reliable detection throughout the device's operation.
Solution Approach 2:
The patent replaces traditional electrical impedance measurement methods with analysis of cardiac electrical signals (electrograms). By substituting the measurement mechanism from impedance-based detection to EGM-based detection, the system achieves more reliable short circuit detection while utilizing existing signal processing capabilities.
2Reliability
If continuous monitoring of cardiac electrical signals is implemented to detect short circuits, then detection reliability improves, but energy consumption increases
Solution Approach 1:
The patent utilizes the cardiac electrical signals that the device already records for its primary function of rhythm monitoring and therapy delivery. By analyzing existing EGM data for short circuit detection, the system achieves continuous monitoring without requiring additional power-consuming dedicated measurement circuits or separate monitoring systems.
Solution Approach 2:
The patent makes the cardiac electrical signal acquisition system serve dual purposes: its original function of rhythm monitoring/therapy triggering and the new function of short circuit detection. This multi-functionality allows continuous monitoring capability while avoiding the energy cost of adding separate dedicated monitoring hardware.
3Measurement precision
If analysis of cardiac electrical signals is used to detect short circuits, then detection precision improves, but processing complexity increases
Solution Approach 1:
The patent extracts specific diagnostic features from the complex cardiac electrical signals, focusing on particular characteristics that indicate short circuits. By isolating and analyzing only the relevant signal features rather than processing the entire signal spectrum, the system achieves high detection precision while managing processing complexity through selective feature extraction.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An implantable medical device capable of sensing cardiac signals and delivering cardiac electrical stimulation therapies is enabled to detect a short circuit of a medical electrical lead. A physiological signal correlated to a motion of a patient is sensed via a physiological sensor. If a lead monitoring condition is met based on the physiological signal, a cardiac signal is acquired and analyzed to detect an abnormality. The short circuit of the medical electrical lead is detected in response to detecting the abnormality.