Deep Breathing Heart Rate Variability is Associated with Inspiratory Muscle Weakness in Chronic Heart Failure. (27th August 2013)

• Record Type: Journal Article
• Authors: Reis, Michel Silva; Arena, Ross; Archiza, Bruno; de, Carlos Fischer; Catai, Aparecida Maria; Borghi‐Silva, Audrey
• Is Part Of: Physiotherapy research international. Volume 19:Number 1(2014:Mar.)
• Page Start: 16
• Page End: 24
• Publication Date: 2013-08-27
• Subjects: Physical therapy -- Periodicals; Physical Therapy Modalities -- Periodicals; Physiothérapie -- Périodiques; 615.82
• DOI: 10.1002/pri.1552
• Languages: English
• ISSNs: 1358-2267

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <sec id="pri1552-sec-0001" sec-type="section"> <title>Background and Purpose</title> <p>There is a synchronism between the respiratory and cardiac cycles. However, the relationship of inspiratory muscle weakness in chronic heart failure (CHF) on cardiac autonomic modulation is unknown. The purpose of the present investigation was to evaluate the impact of inspiratory muscle strength on the magnitude of respiratory sinus arrhythmia.</p> </sec> <sec id="pri1552-sec-0002" sec-type="section"> <title>Methods</title> <p>Ten CHF (62 ± 7 years — left ventricle eject fraction of 40 ± 5% and New York Heart Association class I–III) and nine matched‐age healthy volunteers (64 ± 5 years) participated in this study. Heart rate variability (HRV) was obtained at rest and during deep breathing manoeuvre (DB‐M) by electrocardiograph.</p> </sec> <sec id="pri1552-sec-0003" sec-type="section"> <title>Results</title> <p>CHF patients demonstrated impaired cardiac autonomic modulation at rest and during DB‐M when compared with healthy subjects (<italic>p</italic> < 0.05). Moreover, significant and positive correlations between maximal inspiratory pressure and inspiratory–expiratory differences (<italic>r</italic> = 0.79), expiratory/inspiratory ratio (<italic>r</italic> = 0.83), root mean square of the successive differences (<italic>r</italic> = 0.77), standard deviation of NN intervals (<italic>r</italic> = 0.77), low frequency (<italic>r</italic> = 0.77), and high frequency (<italic>r</italic> = 0.70) were found during DB‐M. At rest, significant correlations were found also.</p> </sec> <sec id="pri1552-sec-0004" sec-type="section"> <title>Conclusion</title> <p>Patients with CHF presented impaired cardiac autonomic modulation at rest. In addition, cardiac autonomic control of heart rate was associated with inspiratory muscle weakness in CHF. Based on this evidence, recommendations for future research applications of respiratory muscle training can bring to light a potentially valuable target for rehabilitation. Copyright © 2013 John Wiley & Sons, Ltd.</p> </sec> </abstract>