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A ventricular activity cancellation algorithm based on event synchronous adaptive filter for single-lead
Jeon Lee1, Jung-hun Lee, Jong-wook Park
1Daegu Haany University, Daegu, Republic of Korea. leejeon@yonsei.ac.kr
Insights
This study introduces a novel event-synchronous adaptive filter (ESAF) for precise atrial activity (AA) estimation by canceling ventricular activity (VA) in single-lead ECG. The ESAF algorithm offers improved performance and real-time implementation capabilities.
Area of Science:
- Biomedical Engineering
- Cardiovascular Physiology
- Signal Processing
Background:
- Accurate atrial activity (AA) analysis is crucial for diagnosing arrhythmias.
- Existing ventricular activity (VA) cancellation algorithms are limited for single-lead ECG.
- Effective VA cancellation is a prerequisite for reliable AA detection.
Purpose of the Study:
- To propose a novel VA cancellation algorithm for single-lead ECG.
- To enhance the accuracy of atrial activity estimation, particularly in atrial fibrillation (AF).
- To develop a computationally efficient and real-time implementable algorithm.
Main Methods:
- Modeled thoracic ECG to develop a novel algorithm.
- Utilized an event-synchronous adaptive filter (ESAF) with ECG as primary input and event-synchronous impulse train (ESIT) as reference.
- Generated ESIT synchronized with VA by QRS complex detection.
- Applied the algorithm to AA estimation in AF electrocardiograms.
Main Results:
- The ESAF-based algorithm demonstrated superior performance compared to the averaged beat subtraction (ABS) method.
- Achieved performance comparable to principal component analysis (PCA) and singular value decomposition (SVD) algorithms.
- An expanded ESAF version showed reasonable performance for AF ECGs with bimorphic VAs.
- The algorithm precisely estimates AA with low computational cost, suitable for real-time implementation.
Conclusions:
- The proposed ESAF algorithm effectively cancels VA in single-lead ECG.
- It enables precise AA estimation, outperforming existing methods like ABS.
- The algorithm's real-time capability and efficiency suggest its potential to replace current standards.
Abstract:
Recently, it has become very important to analyze atrial activity (AA) and to detect arrhythmic AAs and, for this, complete ventricular activity (VA) cancellation is prerequisite. There have been several VA cancellation algorithms for multi-lead ECG but VA cancellation algorithm for single-lead is quite a few. In this study, we have modeled thoracic ECG and, based on this model, proposed a novel VA cancellation algorithm based on event synchronous adaptive filter (ESAF). In this ESAF, the AF ECG was treated as a primary input and event-synchronous impulse train (ESIT) as a reference. And, ESIT was generated so to be synchronized with the ventricular activity by detecting QRS complex. To evaluate the performance, it was applied to the AA estimation problem in atrial fibrillation electrocardiograms. As results, even with low computational cost, this ESAF based algorithm showed better performance than the ABS method and comparable performance to algorithm based on PCA (principal component analysis) or SVD (singular value decomposition). We also proposed an expanded version of ESAF for some AF ECGs with bimorphic VAs and this also showed reasonable performance. Ultimately, our proposed algorithm was found to estimate AA precisely even though it is possible to implement in real-time. We expect our algorithm to replace the most widely used method, that is, the ABS (averaged beat subtraction) method.
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