Multi-site Left Ventricular Pacing Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cardiac resynchronization therapy devices face challenges in delivering optimal multi-site left ventricular pacing, particularly in managing refractory periods, implementing a left ventricular protective period, and switching between left ventricle-only and biventricular-triggered pacing modes, which are not adequately addressed in single-site pacing configurations.
Innovation Solution
The development of a cardiac pacing device with programmable electronic controller and circuitry that manages refractory periods, implements a left ventricular protective period, and facilitates multi-site left ventricular pacing, including biventricular-triggered pacing modes, by using a switch matrix to configure sensing and pacing channels and adjusting pacing parameters to ensure synchronized ventricular contractions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multi-site left ventricular pacing is implemented, then cardiac resynchronization therapy efficacy is improved, but device complexity increases
Solution Approach 1:
The patent divides the left ventricular pacing function into multiple independent pacing sites (LV1, LV2, etc.), each with its own protective period management. This segmentation allows the device to deliver resynchronization therapy to multiple sites while managing complexity through modular control of each site's refractory and protective periods.
Solution Approach 2:
The patent implements nested protective periods where a first protective period for site LV1 is contained within or adjacent to a second protective period for site LV2. This nesting approach allows multiple protective periods to coexist without excessive device complexity, as the controller manages them in a hierarchical manner.
2Reliability
If refractory periods and protective periods are managed for multiple sites, then arrhythmia risk is reduced, but control complexity increases
Solution Approach 1:
The patent establishes protective periods in advance before delivering pacing pulses to each left ventricular site. By pre-defining the protective period duration and timing for each site, the controller avoids complex real-time calculations during pacing delivery, reducing control complexity while maintaining arrhythmia protection.
Solution Approach 2:
Each left ventricular site (LV1, LV2, etc.) has its own locally-managed protective period with site-specific timing and duration parameters. This local quality approach allows the controller to manage refractory and protective periods independently for each site, reducing overall control complexity through localized management rather than global coordination.
3Reliability
If left ventricular protective period is implemented, then pacing safety is improved, but pacing efficiency decreases
Solution Approach 1:
The patent implements periodic protective periods that are temporarily activated during specific phases of the pacing cycle and then expire, allowing normal multi-site pacing to resume. This periodic activation and expiration of protective periods maintains safety during critical phases while preserving pacing efficiency during non-critical phases.
Solution Approach 2:
The protective period parameters (duration, timing, activation) are dynamically adjusted based on the pacing mode and cardiac cycle phase. The controller dynamically enables or disables protective periods for each site depending on whether pacing is being delivered, optimizing the balance between safety and pacing efficiency.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In a pacing mode where the left ventricle is paced upon expiration of an escape interval that is reset by a right ventricular sense, there is the risk that the left ventricular pace may be delivered in the so-called vulnerable period that occurs after a depolarization and trigger an arrhythmia. To reduce this risk, a left ventricular protective period (LVPP) may be provided. Methods and devices for implementing an LVPP in the context of multi-site left ventricular pacing are described.