Chemoreceptor dependence of very low frequency rhythms in advanced
chronic heart failure.
Ponikowski, Piotr, Tuan Peng Chua, Massimo Piepoli, Aham A. Amadi,
Derek Harrington, Katharine Webb-Peploe, Maurizio Volterrani, Roberto
Colombo, Giorgio Mazzuero, Amerigo Giordano, Andrew J. S. Coats.
National Heart & Lung Institute and Royal Brompton Hospital,
London, UK and Centro Medico di Gussago, #Centro Medico di Veruno,
Fondazione "Salvatore Maugeri", Italy
APStracts 3:0350H, 1996.
Factors responsible for very low frequency oscillations
(cycle>30s, VLF) in the cardiovascular system remain obscure. We
tested the hypothesis that increased peripheral chemosensitivity is
important in the pathogenesis of VLF oscillations in patients with
chronic heart failure (CHF). Fourteen male patients with stable,
moderate to severe CHF (age: 60+/-11 years, ejection fraction- 23+/
-11%) and reproducible VLF oscillations in heart rate underwent a
protocol consisting of 3 consecutive 20-minute phases during which
they breathed air, hyperoxia (oxygen via mask, 60% O2 concentration)
and air again. Autoregressive spectral analysis of RR intervals,
blood pressure and respiration was used to quantify total oscillatory
power (TP), VLF, low-(0.04-0.15Hz), and high-frequency power (0.15
-0.40Hz), and the coherence between these signals. Peripheral
chemosensitivity was studied by assessing the ventilatory response to
hypoxia using transient inhalations of pure nitrogen.
Received 12 March 1996; accepted in final form 11 July 1996.
APS Manuscript Number H238-6.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 29 August 1996