Effects of Interval Physical Training on Expiratory Flow Limitation in Recent Myocardial Infarction

Summary

Introduction: Expiratory flow limitation (EFL) and ventilatory inefficiency during dynamic exercise have been identified in patients with recent myocardial infarction (RMI) with preserved ventricular and pulmonary function. However, it is not known what is the prevalence of EFL in this population and what are the effects of physical and respiratory training on this limitation.

Objectives: To evaluate the prevalence of EFL and ventilatory inefficiency during dynamic exercise in individuals with uncomplicated RMI, and to evaluate the effects of interval physical training (IT) in addition to inspiratory muscle training (IMT), exclusive IT and absence of cardiopulmonary rehabilitation (CR) on EFL and ventilatory efficiency.

Methods: 54 patients will be included, divided into three groups with 18 participants each. All will be submitted to evaluations of heart rate variability, hematological and biochemical profile, erythrocytes membrane deformability and stability, inflammatory markers, respiratory pressures, plethysmography, spirometry, carbon monoxide diffusion capacity, ankle brachial index, electrical bioimpedance, echocardiogram, quality of life questionnaires, cardiopulmonary exercise testing and constant load tests. Then, groups 1 (IT) and group 2 (IT + IMT) will participate in a physical training program for 12 weeks and will be re-evaluated after this period. In addition, they will be monitored for a 6 month period after discharge, with returns every two months to measure the energy expenditure through an accelerometer, and at the end of this period they will repeat all the tests again. Group 3 (absence of CR), will consist of patients who do not live in the city or those who can not participate in the CR program for any other reason, and will only participate in the evaluations.

Conditions

• Expiratory Flow Limitation
• Recent Myocardial Infarction

Interventions

OTHER

Interval Training (IT)

Each exercise session will consist of: 1. warm up (10 minutes)- stretches and calisthenics exercises of low to moderate intensity; 2. interval training (IT) - 30 minutes of IT performed in a cycle ergometer, divided into 6 levels of intensity based on the ventilatory anaerobic threshold (VAT) found in CPET: Level 1 - 5 minutes in moderate intensity, at 80% of power reached in VAT; Levels 2 and 4 - 5 minutes of moderate to high intensity, at 100% of VAT; Levels 3 and 5 - 5 minutes of moderate to high intensity, 110% of VAT; Level 6 - 5 minutes in moderate intensity, at 70% of VAT. 3. cooling down (10 minutes) - stretching, and breathing exercises. An CPET will be performed every four weeks to adjust the intensity of training.

OTHER

Inspiratory Muscle Training (IMT)

The IMT session will take place just after the warm-up exercises and consist of 2 series of 12 inspirations with a 60% of Maximal Inspiratory Pressure (MIP) with the equipment POWERbreathe Plus Medic® (POWERbreathe International Ltd, Warwickshire, UK). The patient will be instructed to remain seated with a nasal clip during the IMT series to avoid nasal air leakage and will be asked to inhale quickly and deeply, as quickly as possible, with a 2 minute interval between series. The training load will be adjusted weekly by a new evaluation of MIP to maintain the intensity of the exercise within the proposed value. All the others exercises will be identical between group 1 and 2.

Sponsors & Collaborators

• Universidade Federal de Sao Carlos

  collaborator OTHER

• Federal University of Uberlandia

  lead OTHER

Principal Investigators

• Debora LZ Scheucher, M.S. · Federal University of Uberlandia

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

35 Years

Max Age

80 Years

Sex

MALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2019-07-04

Primary Completion

2021-02-28

Completion

2022-10-31

Countries

• Brazil

Study Locations