The Importance of Visceral Feedbacks: Focus on Chemoreceptors

Chronic heart failure (CHF) is characterized by a resetting of visceral feedbacks, with increased chemo- and ergoreflex sensitivities and reduced baroreflex sensitivity. The discharge rate of peripheral and/or central chemoreceptors may be enhanced in CHF, mostly due to neurohormonal stimulation and/or hypoperfusion of chemosensitive areas; increased chemoreceptor activity may contribute to the development of periodic breathing/Cheyne–Stokes respiration (PB/CSR), but also to sympatho-vagal imbalance, with adrenergic activation and vagal withdrawal. In addition, baroreflex depression and ergoreflex activation could be promoted by increased chemoreflex sensitivity and could contribute to autonomic dysfunction and ventilatory instability, although current evidences are limited.