In 13 decerebrate, artificially ventilated cats preganglionic sympathetic outflow to the heart was recorded with ECG and ventilation signal. A novel algorithm was implemented that extracts weighted events representing burst occurrences and their size. A multiple threshold strategy was used to separate bursts. Weighted events yielded count signals. Spectral analysis of the count signal revealed a predominance of a discharge synchronous to heart beat at cardiac frequency (CF≅3 Hz), a ventilation rhythm at the high frequency (HF≅0.3 Hz) of beat-to-beat variability, and in 9 of 13 cats a Mayer's wave lower frequency (LF). The CF component was ∼50% larger in power than both HF and also LF (when present). Spectral analysis at increasing count levels (i.e., with only the events with a weight ≥ the considered level) indicated that all rhythms were carried by burst activity and its modulations. A modulation index of HF over CF, MIHF/CF was extracted from dynamic (i.e., ventilation cycle by ventilation cycle) folded histograms of counts. MIHF/CF was significantly higher in the group without LF (0.65±0.20, mean±SD, n=4) than in that with LF (0.41±0.07, n=9). Burst activity can be a key element in the interactions between cardiovascular variability rhythms.
Burst activity and heart rhythm modulation in the sympathetic outflow to the heart / G. Baselli, C. Falcomatà, F. Gelain, S. Cerutti, M. Massimini, N. Montano, A. Porta - In: Engineering in Medicine and Biology Society, 2001 : Proceedings of the 23. Annual International Conference of the IEEE[s.l] : IEEE, 2001. - ISBN 0-7803-7211-5. - pp. 582-584 (( Intervento presentato al 23. convegno Annual International Conference of the IEEE EMBS tenutosi a Istanbul nel 2001.
|Titolo:||Burst activity and heart rhythm modulation in the sympathetic outflow to the heart|
MONTANO, NICOLA (Penultimo)
PORTA, ALBERTO (Ultimo)
|Settore Scientifico Disciplinare:||Settore ING-INF/06 - Bioingegneria Elettronica e Informatica|
Settore MED/09 - Medicina Interna
Settore BIO/09 - Fisiologia
|Data di pubblicazione:||2001|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1109/IEMBS.2001.1019000|
|Tipologia:||Book Part (author)|
|Appare nelle tipologie:||03 - Contributo in volume|