Removing ventricular far-field signals in intracardiac electrograms during stable atrial tachycardia using the periodic component analysis

- New artifact removal technique awarded YIA in ICE 2014.
- Intraatrial electrograms can be compromised by ventricular far-fields.
- Highly regular morphologies during atrial flutter pose problems to common algorithms.
- Periodic component analysis (πCA) is introduced as an artifact removal method.
- Morphology of atrial activity is successfully retained using πCA.

BackgroundIntracardiac electrograms are an indispensable part during diagnosis of supraventricular arrhythmias, but atrial activity (AA) can be obscured by ventricular far-fields (VFF). Concepts based on statistical independence like principal component analysis (PCA) cannot be applied for VFF removal during atrial tachycardia with stable conduction.MethodsA database of realistic electrograms containing AA and VFF was generated. Both PCA and the new technique periodic component analysis (πCA) were implemented, benchmarked, and applied to clinical data.ResultsThe concept of πCA was successfully verified to retain compromised AA morphology, showing high correlation (cc = 0.98 ± 0.01) for stable atrial cycle length (ACL). Performance of PCA failed during temporal coupling (cc = 0.03 ± 0.08) but improved for increasing conduction variability (cc = 0.77 ± 0.14). Stability of ACL was identified as a critical parameter for πCA application. Analysis of clinical data confirmed these findings.ConclusionπCA is introduced as a powerful new technique for artifact removal in periodic signals. Its concept and performance were benchmarked against PCA using simulated data and demonstrated on measured electrograms.