Ultra-high-frequency electrocardiography

Pavel Jurak1, Pavel Leinveber2, Filip Plesinger1, Karol Curila3, Ivo Viscor4, Vlastimil Vondra4, Magdalena Matejkova5, Lucie Znojilova6, Radovan Smisek7, Jolana Lipoldova8, Frits Prinzen9, Josef Halamek10
1Institute of Scientific Instruments of the CAS, 2International Clinical Research Center, St. Anne’s University Hospital, Brno, Czech Republic, 3Cardiocenter FNKV and 3rd Faculty of Medicine in Prague, 4Institute of Scientific Instruments, the Czech Academy of Sciences, 5International Clinical Research Center, St. Anne's University Hospital, Brno, Czech Republic, 6Cardiocenter of University Hospital Kralovske Vinohrady, 7Brno University of Technology, Faculty of Electrical Engineering and Communication, Department of Biomedical Engineering, 8St. Anne´s University Hospital, 9Department of Physiology, Maastricht University Medical Center, 10Institute of Scientific Instruments, CAS, CZ

Abstract

Background: Electrocardiography (ECG) is a technique more than 100 years old. The parameters obtained from the ECG are derived from various mor-phologies of individual waves in the low-frequency ECGs (P, QRS, and T). We introduce a new technology that uses the ultra-high-frequency compo-nents (150-1000 Hz) of the ECG (UHF-ECG). Method: The UHF-ECG components represent weak signals generated during depolarization of myocardial cells (phase 0 of action potential). The ampli-tude of UHF oscillations decreases with distance from the source. This prop-erty and the different timing of depolarization in the ventricles' volume ena-ble to map the ventricular activation from the chest ECG leads. Because of a low signal-to-noise ratio of UHF oscillations, averaging in both the time and frequency domains must be used. One recording thus lasts 30 seconds and more. Results: UHF-ECG defines the time-spatial distribution of myocardial elec-trical activity. Corresponding numerical parameters are electrical dyssyn-chrony (e-DYS) and the duration of local depolarization (Vd). UHF ventricu-lar depolarization maps present details of electrical activation. Conclusion: The UHF-ECG uses a new source of information originated in ventricular volumes that is different from the standard ECG. It is possible to map the volumetric electrical activation associated with mechanical contrac-tion. Its primary clinical utilization is in cardiac resynchronization, pacing optimization, and conduction system pacing.