The ergoreflex: how the skeletal muscle modulates ventilation and cardiovascular function in health and disease

Abstract

The control of ventilation and cardiovascular function during physical activity is partially regulated by the ergoreflex, a cardiorespiratory reflex activated by physical activity. Two components of the ergoreflex have been identified: the mechanoreflex, which is activated early by muscle contraction and tendon stretch, and the metaboreflex, which responds to the accumulation of metabolites in the exercising muscles. Patients with heart failure (HF) often develop a skeletal myopathy with varying degrees of severity, from a subclinical disease to cardiac cachexia. HF‐related myopathy has been associated with increased ergoreflex sensitivity, which is believed to contribute to dyspnoea on effort, fatigue and sympatho‐vagal imbalance, which are hallmarks of HF. Ergoreflex sensitivity increases significantly also in patients with neuromuscular disorders. Exercise training is a valuable therapeutic option for both HF and neuromuscular disorders to blunt ergoreflex sensitivity, restore the sympatho‐vagal balance, and increase tolerance to physical exercise. A deeper knowledge of the mechanisms mediating ergoreflex sensitivity might enable a drug or device modulation of this reflex when patients cannot exercise because of advanced skeletal myopathy.

Determinants of ventilatory inefficiency in transthyretin cardiac amyloidosis: The role of excessive ventilatory drive

“…Small unmyelinated fibres amyloid damage may also alter mechano-reflex and metabo-reflex, so called ergoreflex, which modulates ventilation and cardiovascular function during exercise (Boyes et al, 2022). Ergoreflex sensitivity is typically overstimulated in heart failure contributing to sympathetic outflow increase and sympathovagal imbalance (Aimo et al, 2021;Boyes et al, 2022). Whereas ergoreflex sensitivity was not evaluated in our study in CA patients, we found that post-exercise heart rate recovery, a robust surrogate of cardiac autonomic imbalance, was markedly impaired in CA patients and correlated with ventilatory inefficiency.…”

“…Whereas ergoreflex sensitivity was not evaluated in our study in CA patients, we found that post-exercise heart rate recovery, a robust surrogate of cardiac autonomic imbalance, was markedly impaired in CA patients and correlated with ventilatory inefficiency. Hence, together with impaired autonomic cardiopulmonary regulation via peripheral (carotid body) and central (medullary) chemoreceptors, excessive stimulation of ergoreceptors (Aimo et al, 2021;Boyes et al, 2022) may have heightened the sympathetic activity converging to hyperventilation and increased V E -VCO 2 slope. Further studies aimed to test whether the ergoreflex is impaired in CA patients are warranted.…”

Overstimulation of the ergoreflex—A possible mechanism to explain symptoms in long COVID

“…The metaboreflex causes blood pressure to rise to ensure adequate perfusion of the exercising muscle. Animal models show that mechanical stimulation of muscles and tendons also leads to increase heart rate and blood pressure; this is known as the "mechanoreflex" (8).…”

“…Signals from both components integrate with other peripheral and central signals (such as the chemoreflex and baroreflex) in the central nervous system. The efferent limb of the reflex results in increased ventilation and sympathetic activation, in turn causing peripheral resistance and cardiac output to rise, thereby maintaining systemic blood pressure (Figure 1) (8).…”

September 2021 at a glance: focus on biomarkers, sex differences and adherence to medical treatment

“…HF patients often develop skeletal myopathy, 17 which is associated with increasing ergoreflex sensitivity and dyspnoea on effort. Exercise training represents a valuable strategy to reduce such sensitivity and increase exercise tolerance 18 …”