Chamber-Specific Impedance Characterization for Pacemaker Timing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for configuring pacemakers and cardiac resynchronization therapy devices rely on time-consuming echocardiography evaluations and rough estimates from intra-cardiac electrograms, which may not accurately reflect individual patient needs, especially when patients become ambulatory and active.
Innovation Solution
A method and system that collect cardiac signals and dynamic impedance data to characterize chamber-specific functions, using a CSF vector to form a DI data set aligned with specific cardiac timing features, allowing for the analysis of chamber-specific indicators to adjust therapy configurations and improve hemodynamic support.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If echocardiography evaluation method is used to select AV and VV delays, then measurement precision is improved, but loss of time increases
Solution Approach 1:
The patent replaces the mechanical/electronic echocardiography system with an electrical measurement system. Instead of using ultrasound imaging to assess cardiac function, the invention uses electrical impedance measurements taken during pacemaker pacing to characterize chamber-specific functions and determine optimal timing parameters.
Solution Approach 2:
The pacemaker device performs self-characterization of cardiac function using its own pacing and sensing capabilities. The device autonomously measures dynamic impedance, identifies timing features, and determines optimal AV/VV delays without requiring external echocardiography equipment or clinician intervention during the characterization process.
2Loss of time
If device-based methods using P-wave duration are used to estimate intra-atrial conduction time, then loss of time is reduced, but measurement precision deteriorates
Solution Approach 1:
The patent introduces dynamic impedance measurement as an intermediary parameter that bridges the gap between simple timing measurements and complex cardiac function assessment. Instead of directly measuring conduction time from P-wave duration (which is indirect and inaccurate), the system measures impedance changes that directly reflect chamber-specific mechanical function and timing.
Solution Approach 2:
The invention changes the measurement parameter from electrical timing (P-wave duration) to electrical impedance (dynamic impedance). This parameter transformation allows the system to capture chamber-specific functional information that is not available through traditional ECG timing measurements, thereby improving precision while maintaining speed.
3Measurement precision
If comprehensive echocardiography evaluation is performed to tailor device to individual patient, then measurement precision is improved, but loss of time increases
Solution Approach 1:
The patent segments the cardiac function assessment into chamber-specific measurements. Instead of performing a comprehensive global echocardiography evaluation, the system independently characterizes each chamber's function (atria and ventricles separately) using localized impedance measurements, allowing for individualized therapy settings without the time cost of full echocardiography.
Solution Approach 2:
The invention uses dynamic impedance measurements taken during actual pacemaker operation rather than static echocardiography images. The system measures impedance changes in real-time during the cardiac cycle, capturing dynamic chamber-specific function that reflects the patient's actual physiological state during ambulatory activity.
4Ease of operation
If pacemaker parameters are set in clinic to preferred settings, then ease of operation is improved, but adaptability deteriorates
Solution Approach 1:
The patent implements a feedback mechanism where the pacemaker continuously monitors dynamic impedance during ambulatory activity and uses this information to automatically adjust timing parameters. The system compares current impedance measurements with stored reference data and autonomously modifies AV/VV delays to maintain optimal chamber-specific function during physical activity.
Solution Approach 2:
The invention transitions from static clinic-based parameter settings to dynamic ambulatory-based parameter adjustment. The pacemaker system continuously adapts timing parameters in response to real-time impedance changes that occur during physical activity, ensuring optimal performance across different activity levels rather than being fixed for a single clinic visit.
Data Source
AI summary
A method and system are provided for characterizing chamber specific function. The method and system comprise collecting cardiac signals associated with asynchronous timing between first and second chambers of the heart; collecting dynamic impedance (DI) data along a chamber-specific function (CSF) vector to form a DI data set, the DI data set collected during a collection window that is temporally aligned based on a timing feature of interest (FOI); repeating the collection operations over multiple cardiac cycles (CC) to obtain an ensemble of DI data sets; and combining the ensemble of DI data sets to form a composite DI data set that is coupled to a chamber functional mechanic of interest (FMOI) associated with the first chamber and decoupled from functional mechanics associated with the second chamber; and analyzing the composite DI data set to obtain a CSF indicator associated with the chamber FMOI of the first chamber.