Unraveling the Role of Respiratory Muscle Metaboloreceptors under Inspiratory Training in Patients with Heart Failure

Abstract

Exercise intolerance may be considered a hallmark in patients who suffer from heart failure (HF) syndrome. Currently, there is enough scientific evidence regarding functional and structural deterioration of skeletal musculature in these patients. It is worth noting that muscle weakness appears first in the respiratory muscles and then in the musculature of the limbs, which may be considered one of the main causes of exercise intolerance. Functional deterioration and associated atrophy of these respiratory muscles are related to an increased muscle metaboreflex leading to sympathetic–adrenal system hyperactivity and increased pulmonary ventilation. This issue contributes to increased dyspnea and/or fatigue and decreased aerobic function. Consequently, respiratory muscle weakness produces exercise limitations in these patients. In the present review, the key role that respiratory muscle metaboloreceptors play in exercise intolerance is accurately addressed in patients who suffer from HF. In conclusion, currently available scientific evidence seems to affirm that excessive metaboreflex activity of respiratory musculature under HF is the main cause of exercise intolerance and sympathetic–adrenal system hyperactivity. Inspiratory muscle training seems to be a useful personalized medicine intervention to reduce respiratory muscle metaboreflex in order to increase patients’ exercise tolerance under HF condition.

Application of Inspiratory Muscle Training to Improve Physical Tolerance in Older Patients with Ischemic Heart Failure

“…At the same time, it is worth pointing out that excessive metaboreflex of the respiratory muscles in patients with HF may be one of the reasons for exercise intolerance. It has been shown that the use of an individually adjusted IMT can reduce this response [ 30 ].…”

Effects of pulmonary rehabilitation on cardiac magnetic resonance parameters in patients with persistent dyspnea following pulmonary embolism

“…Although only SOBQ improvement was reported in the present study, it has to be emphasized that the effects of rehabilitation are not limited to improvement of dyspnea or to the increase in exercise capacity. Dyspnea and reduced exercise capacity are considered multifactorial and impaired skeletal muscle function may play a central role in the development of these symptoms rather than cardiopulmonary dysfunction [49] , [50] . An augmented “ergoreflex” stimulation due to reduced muscular capacity for aerobic metabolism might result in maladaptive increased ventilation leading to dyspnea and fatigue.…”

Concurrent Validity and Reliability of Manual Versus Specific Device Transcostal Measurements for Breathing Diaphragm Thickness by Ultrasonography in Lumbopelvic Pain Athletes

“…This novel tool should be studied in other musculoskeletal conditions that are different from lumbopelvic pain, such as neck pain [ 46 ] or heart failure [ 49 , 50 ] since inspiratory muscle training has shown great benefits in these patients. In addition, randomized clinical trials assessing the effects of diaphragm re-education based on visual biofeedback using this novel holding device for the probe fixation could improve signs and symptoms shown by athletes who are suffering from non-specific lumbopelvic pain [ 30 , 47 , 48 ].…”