Coronary Artery Disease, Heart Failure, Myocardial Infarction
Conditions
Keywords
Exercise training, High intensity interval training, left ventricular systolic function, G-protein related kinase 2, heart failure, myocardial infarction, coronary artery disease, beta adrenergic receptor
Brief summary
Patients who have suffered a heart attack are at risk of developing worsening heart function and heart failure. Exercise training has a beneficial effect on heart function and prevents heart failure. The aim of the current study is to investigate the effect of exercise training on heart function in patients who have suffered a heart attack.
Detailed description
Patients who have suffered a myocardial infarction are at significant risk for developing heart failure and progressive left ventricular dysfunction One of the proposed mechanisms responsible for this observation is reduction in myocardial beta-adrenergic receptor density due to elevated cell membrane protein G - protein coupled receptor kinase -2 (GRK2). It is known that exercise training preserves heart function in patients who have suffered a myocardial infarction. The mechanism for this is not clear. The purpose of this study is to examine the effect of exercise training on myocardial function and GRK2 levels in patients who have suffered a myocardial infarction, with the hypothesis that exercise training in this population reduces GRK2 levels and preserves or improves myocardial function.
Interventions
OTHERSecondary prevention and cardiac rehabilitation clinic
Secondary prevention and cardiac rehabilitation clinic of the Montreal Heart Institute. Subjects will undergo twice weekly exercise training with high intensity interval training for a period of 12 weeks.
Sponsors
Montreal Heart Institute
Study design
Allocation
RANDOMIZED
Intervention model
SINGLE_GROUP
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Acute myocardial infarction * Complete revascularization: no residual major epicardial coronary artery coronary stenosis ≥ 70%; no residual left main coronary stenosis ≥ 40%. * Stage A-C heart failure, New York Heart Association class I-III. * Stable dose of medications during the 4 weeks prior to enrolment. * Able to perform a maximal cardiopulmonary stress test. * Capacity and willingness to provide sign informed consent.
Exclusion criteria
* Pregnant * Coronary artery bypass surgery: patients post coronary artery bypass graft exhibit wall motion abnormalities that may interfere with speckle tracking analysis. * Incomplete revascularization with major epicardial coronary artery (left anterior descending, circumflex, or right coronary) stenosis ≥ 70%. * Myocardial necrosis in the absence of significant flow limiting coronary artery stenosis or thrombosis, with the exception of documented STEMI and successful thrombolytic therapy resulting on no significant residual epicardial coronary artery stenosis. * Significant valvular disease that is greater than moderate in severity * History of non-ischemic cardiomyopathy (dilated, restrictive, infiltrative cardiomyopathy, hypertrophic, LV non compaction, or Takotsubo cardiomyopathy) * Significant resting ECG abnormalities that preclude accurate speckle tracking. * Paced rhythm. * left bundle branch block * Atrial arrhythmias (ex. persistent/permanent atrial fibrillation, atrial flutter). * Frequent ventricular ectopics * Significant ventricular arrhythmias (non-sustained ventricular tachycardia or syncope). * New York Heart Association class IIIb - IV symptoms. * Severe LV systolic dysfunction (Ejection fraction ≤ 30%) * Active decompensated heart failure with orthopnea or paroxysmal nocturnal dyspnea. * Uncontrolled resting arterial hypertension \> 180/110 mmHg. * More than moderate systemic disease * Chronic inflammation or infection. * Any contraindication to exercise training or any condition limiting ability to partake in adequate exercise stress testing or training (peripheral artery disease, articular, neurologic, or psychiatric pathology)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Lymphocyte GRK2 mRNA level | at baseline and following 12 weeks exercise training intervention | change in lymphocyte GRK2 mRNA levels |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Left ventricular systolic function | at baseline and following 12 weeks exercise training intervention | change in left ventricular systolic function |
| Left ventricular dimensions | at baseline and following 12 weeks exercise training intervention | Change in left ventricular dimensions |
| Plasma epinephrine | at baseline and following 12 weeks exercise training intervention | change in plasma epinephrine |
| heart rate variability | at baseline and following 12 weeks exercise training intervention | change change in autonomic tone |
| exercise capacity (VO2max) | at baseline and following 12 weeks exercise training intervention | Change before and after exercise training |
| Maximal cardiac output and stroke volume using electrical bioimpedance | at baseline and following 12 weeks exercise training intervention | change in maximal cardiac output and stroke volume |
| lymphocyte GRK2 protein levels | at baseline and following 12 weeks exercise training intervention | change in lymphocyte GRK2 protein levels |
| ambulatory blood pressure | at baseline and following 12 weeks exercise training intervention | Change in awake and 24h blood pressure |
| Plasma brain natriuretic peptide | at baseline and following 12 weeks exercise training intervention | change in plasma brain naturietic peptide |
Other
| Measure | Time frame | Description |
|---|---|---|
| Fasting glucose | at baseline and following 12 weeks exercise training intervention | change in fasting glucose |
| serum lipids | at baseline and following 12 weeks exercise training intervention | change in serum lipids |
Countries
Canada
Outcome results
None listed