Patients with chronic heart failure (CHF) experience a myriad of symptoms that greatly impact their lives. In particular, sufferers of CHF tend to have greatly impaired autonomic cardiac control, constrictive blood vessel activity, and reduced respiratory muscle strength. All of these could contribute to the experienced fatigue, dyspnea and exercise intolerance common with the CHF diagnosis.
One of the recent developments in the area of CHF has been inspiratory muscle training. Inspiratory muscle training (IMT) was tested to improve autonomic cardiac function, respiratory muscle strength and blood vessel sympathetic activity in CHF patients. Let’s take a look at the study in a little more depth below.
- People with chronic heart failure (CHF) show respiratory muscle weakness, greatly impaired autonomic cardiac control, and constrictive blood vessel activity, all of which contribute to fatigue, dyspnea and exercise intolerance.
- 12 weeks of RMT improved respiratory muscle strength, cardiopulmonary exercise performance, and quality of life in CHF patients.
- RMT specifically modulated the low and high frequency components of heart rate variability and decreased the LF/HF ratio.
- RMT also decreased resting muscle sympathetic nerve activity.
RMT effectively improves clinically relevant cardiac parameters, autonomic cardiac control and sympathetic nerve activity in people with CHF.
CHF patients underwent cardiopulmonary exercise testing, muscle sympathetic nerve activity, blood pressure and pulse variability and quality of life. These factors were assessed before and after 3 months of IMT. In addition, the patients in the study group were compared to a control group in order to best assess the effect of IMT.
The study found that inspiratory muscle strength and cardiopulmonary exercise performance were significantly increased due to IMT in patients with CHF when compared to the control group. IMT also significantly decreased the low frequency (LF) component and increased the high frequency (HF) component of heart rate variability, and decreased the LF/HF ratio. Finally, IMT significantly decreased resting muscle sympathetic nerve activity and increased the quality of life for the patients studied.
The study is clear: IMT significantly improves clinically relevant cardiac parameters and autonomic cardiac control, decreases muscle sympathetic nerve activity, which is linked to hypertension, and improves quality of life. These findings therefore show that IMT can directly improve some of the factors causing CHF.