Abstract:
:The fraction of repolarization variability independent of RR interval variability is of clinical interest. It has been linked to direct autonomic nervous system (ANS) regulation of the ventricles in healthy subjects and seems to reflect the instability of the ventricular repolarization process in heart disease. In this study, we sought to identify repolarization measures that best reflect the sympathetic influences on the ventricles independent of the RR interval. ECG was recorded in 46 young subjects during supine and then following 45 degrees head-up tilt. RR intervals and five repolarization features (QTend, QTpeak, RTend, RTpeak, and TpTe) were extracted from the ECG recordings. Repolarization variability was separated into RR-dependent and RR-independent variability using parametric spectral analysis. Results show that LF power of TpTe is independent of RR in both supine and tilt, while the LF power of QTend and RTend independent of RR and respiration increases following tilt. We conclude that TpTe is independent of RR and is highly affected by respiration. QTend and RTend LF power might reflect the sympathetic influences on the ventricles elicited by tilt. Graphical abstract.
journal_name
Med Biol Eng Computjournal_title
Medical & biological engineering & computingauthors
El-Hamad F,Javorka M,Czippelova B,Krohova J,Turianikova Z,Porta A,Baumert Mdoi
10.1007/s11517-019-01998-9subject
Has Abstractpub_date
2019-08-01 00:00:00pages
1753-1762issue
8eissn
0140-0118issn
1741-0444pii
10.1007/s11517-019-01998-9journal_volume
57pub_type
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