Implantable Cardiac Stimulator Post-Shock Data Manipulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current implantable cardiac stimulus devices face challenges in accurately detecting cardiac events following the delivery of defibrillation or cardioversion stimuli, as post-shock signals may resemble pre-shock signals, leading to potential misinterpretation and inappropriate therapy.
Innovation Solution
The method involves manipulating stored cardiac event rate and amplitude data post-stimulus delivery to simulate a different cardiac state, using dynamic and non-dynamic detection thresholds to differentiate between states, and seeding data to invoke a non-tachycardia state after therapy, allowing for reevaluation of cardiac signals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If cardiac event rate data is manipulated following stimulus delivery to simulate low cardiac event rate, then the device can prevent false detection of noise and invoke appropriate non-tachycardia state, but the device complexity increases due to data manipulation requirements
Solution Approach 1:
The patent applies preliminary action by pre-defining multiple cardiac states (tachycardia, non-tachycardia, post-shock) with predetermined detection thresholds and analysis criteria. Following stimulus delivery, the device automatically transitions to the post-shock state with pre-configured parameters, eliminating the need for complex real-time decision-making algorithms and reducing overall device complexity while maintaining high reliability.
Solution Approach 2:
The patent implements parameter changes by dynamically adjusting detection thresholds and analysis criteria based on the current cardiac state. Different states have different threshold values and detection parameters, allowing the device to adapt to varying post-stimulus conditions. This state-dependent parameter adjustment simplifies the detection logic while improving accuracy in distinguishing true cardiac events from noise.
2Measurement precision
If multiple detection thresholds and states are implemented to differentiate cardiac states, then the device can accurately distinguish between malignant and non-malignant arrhythmias, but the device complexity increases
Solution Approach 1:
The patent applies segmentation by dividing cardiac rhythm detection into distinct states (tachycardia, non-tachycardia, post-shock), each with its own detection thresholds and analysis criteria. This segmentation allows the device to apply simplified, state-specific detection logic rather than complex universal algorithms, improving measurement precision while managing device complexity through modular state-based processing.
Solution Approach 2:
The patent implements dynamics by allowing the device to transition between different detection states based on detected cardiac events and stimulus delivery. The detection thresholds and analysis criteria dynamically adapt to the current state, enabling accurate differentiation of arrhythmia types while maintaining manageable device complexity through state-machine architecture.
3Reliability
If cardiac event amplitude data is seeded to simulate large amplitude cardiac signal, then the device can force analysis into non-tachycardia state following therapy, but loss of time occurs due to data manipulation
Solution Approach 1:
The patent applies preliminary action by pre-configuring the post-shock state with predetermined amplitude values and detection parameters before stimulus delivery. Immediately following stimulus delivery, the device seeds the amplitude data with pre-calculated values appropriate for the expected post-conversion state, minimizing processing time while ensuring accurate state detection. This pre-prepared approach reduces the time penalty of data manipulation.
4Reliability
If data manipulation is performed to prevent false detection following stimulus delivery, then unnecessary stimuli are reduced, but the device complexity increases due to additional processing requirements
Solution Approach 1:
The patent introduces an intermediary post-shock state that acts as a buffer between stimulus delivery and resumption of normal rhythm analysis. This intermediate state has specialized detection criteria designed to filter out post-stimulus noise while allowing true cardiac events to be detected. The intermediary state simplifies the overall detection logic by providing a dedicated transition phase, reducing device complexity while improving therapy delivery accuracy.
Data Source
AI summary
Methods of cardiac rhythm analysis in an implantable cardiac stimulus device, and devices configured for such methods. In an illustrative embodiment, certain data relating to cardiac event rate or amplitude is modified following delivery of a cardiac stimulus. In another embodiment, cardiac rhythm analysis is performed using one of plural states, with the plural states using different criteria, such as a detection threshold, to detect cardiac events in a sensed signal. Following delivery of a cardiac stimulus, data is manipulated to force the analysis into one of the states, where stimulus is delivered, in the illustrative embodiment, only after a different state is invoked. Implantable devices incorporating operational circuitry for performing such methods are also included in other illustrative embodiments.