A beat-by-beat analysis of electrocardiograms from cardiac transplant recipients |
| |
Affiliation: | 1. Department of Biochemistry, Faculty of Medicine, Urmia University of Medical Sciences, Urmia, Iran;2. Neurophysiology Research Center, Cellular and Molecular Medicine Institute, Urmia University of Medical Sciences, Urmia, Iran;3. Department of anatomical sciences, Faculty of Medicine, Urmia University of Medical Sciences, Urmia, Iran;4. Department of Physiology, Faculty of Medicine, Urmia University of Medical Sciences, Urmia, Iran;5. Faculty of Medicine, Urmia University of Medical Sciences, Urmia, Iran |
| |
Abstract: | A software system is described for producing a beat-by-beat analysis of the electrocardiograms from patients after heart transplantation. Pacemaker spikes are automatically detected and eliminated from the signals. R waves are located by a robust and accurate two-step algorithm. Based on the variable length of single heart beats, the Fourier coefficients of three orthogonal surface leads and of two intracardiac leads are calculated beat-by-beat. Power spectra are then obtained by combining contributions from the variable fundamental frequency and its multiples (harmonics) into fixed frequency classes of 1 Hz width and averaging over 60–120 cardiac cycles. Additionally, averaged beat-by-beat power spectra are calculated for windowed QRS complexes and T waves. As by-products, single beat quantities, such as R-R and R-T intervals, averaged signals for all leads, and the orientational autocorrelation function of the electrical vector of the heart, are obtained. Following beat-by-beat evaluation, mean values and standard deviations are obtained for all quantities. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|