Yoga and breathing technique training in patients with heart failure and preserved ejection fraction: study protocol for a randomized clinical trial

Abstract

Background: Current therapies for heart failure (HF) are followed by strategies to improve quality of life and exercise tolerance, besides reducing morbidity and mortality. Some HF patients present changes in the musculoskeletal system and inspiratory muscle weakness, which may be restored by inspiratory muscle training, thus increasing respiratory muscle strength and endurance, maximal oxygen uptake (VO2), functional capacity, respiratory responses to exercise, and quality of life. Yoga therapies have been shown to improve quality of life, inflammatory markers, and peak VO2 mostly in HF patients with a reduced ejection fraction. However, the effect of different yoga breathing techniques in patients showing HF with a preserved ejection fraction (HFpEF) remain to be assessed.

Methods/design: A PROBE (prospective randomized open blinded end-point) parallel-group trial will be conducted at two specialized HF clinics. Adult patients previously diagnosed with HFpEF will be included. After signing informed consent and performing a pre-test intervention, patients will be randomized into three groups and provided with either (1) active yoga breathing techniques; (2) passive yoga breathing techniques (pranayama); or and (3) control (standard pharmacological treatment). Follow-up will last 8 weeks (16 sessions). The post-intervention tests will be performed at the end of the intervention period for analysis of outcomes. Interventions will occur continuously according to patients' enrollment. The main outcome is respiratory muscular resistance. A total of 33 enrolled patients are expected. The present protocol followed the SPIRIT guidelines and fulfilled the SPIRIT checklist.

Discussion: This trial is probably the first to assess the effects of a non-pharmacological intervention, namely yoga and specific breathing techniques, to improve cardiorespiratory function, autonomic system, and quality of life in patients with HFpEF.

Trial registration: REBEC Identifier: RBR-64mbnx (August 19, 2012). Clinical Trials Register: NCT03028168 . Registered on 16 January 2017).

Keywords: Autonomic system; Heart failure with preserved ejection fraction; Maximal inspiratory pressure; Maximal oxygen uptake; Randomized controlled trial; Respiratory techniques; Yoga.

Conflict of interest statement

Ethics approval and consent to participate

All participants will read and sign an informed consent form before beginning the study. All team members have been trained to introduce, show and take questions about the informed consent, exams to be performed, and eventually discomforts associated to interventions before patients signing the informed consent. The study protocol has been approved by the HCPA Institutional Review Board (protocol number 11–0069) and will be conducted according to the principles of the Declaration of Helsinki and in compliance with the Brazilian legal and regulatory framework for research involving human beings.

This protocol was registered in the ClinicalTrial.gov under identifier number NCT03028168 (January 16, 2017) and in the Brazilian Records of Clinical Trials (REBEC) with the identifier number: RBR-64mbnx (19 August 2012) and the last update was performed on September 2, 2013.

The ethical bodies of the Hospital de Clínicas de Porto Alegre (IRB 00000921) and from Hospital ULBRA-Mãe de Deus (Registration Number at Plataforma Brasil: 5349).

For their own safety, patients will be followed up after the end of the protocol in the outpatient services of the Hospital de Clínicas of Porto Alegre and the University Hospital ULBRA-Mãe de Deus.

Consent for publication

The consent for publication was included in the consent to participate form.

Competing interests

The authors declare that they have no competing interests.

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Figures

Fig. 1

Flowchart of study participation and intervention

Fig. 2

Schedule of enrollment, interventions, and assessments