Background: Intracardiac electrograms are an indispensable part during diagnosis of supraventriculararrhythmias, but atrial activity (AA) can be obscured by ventricular far-fields (VFF). Concepts based onstatistical independence like principal component analysis (PCA) cannot be applied for VFF removalduring atrial tachycardia with stable conduction.Methods: A database of realistic electrograms containing AAand VFF was generated. Both PCA and thenew technique periodic component analysis (πCA) were implemented, benchmarked, and applied toclinical data.Results: The 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 ofPCA failed during temporal coupling (cc = 0.03 ± 0.08) but improved for increasing conductionvariability (cc = 0.77 ± 0.14). Stability of ACL was identified as a critical parameter for πCAapplication. Analysis of clinical data confirmed these findings.Conclusion: πCA 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 demonstratedon measured electrograms.
An imaging apparatus and method are provided. The probe for an imaging apparatus includes a manually manipulable proximal portion; a straight distal portion with a distal tip for locating at a site to define an observational field; and a curved portion between the proximal portion and the distal portion. The imaging method includes the steps of locating a distal tip of an imaging probe at a site to define an observational field; irradiating the observational field from the distal tip; and collecting a return signal at the distal tip; wherein the probe comprises a manually manipulable proximal portion. The apparatus and method provided herein are useful for various applications including but not limited to endomicroscopy and other microsurgical procedures performed under optical stereoscopic magnified visualization, such as neurosurgery, ENT/facial surgery and spinal surgery.
Student Theses (2)
D.-T. Rudolph. Advanced signal processing algorithms to remove ventricular far field artifacts from intracardiac electrograms. Institute of Biomedical Engineering, Karlsruhe Institute of Technology (KIT). Masterarbeit. 2014
D.-T. Rudolph. Non-invasive imaging of cardiac conduction velocities. Institute of Biomedical Engineering, Karlsruhe Institute of Technology (KIT). Bachelorarbeit. 2012