Interval Training in Cardiac Rehabilitation: Effects on Cardiorespiratory Fitness and Platelet Function - A Randomized Controlled Trial
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- Medical University of Vienna
- Enrollment
- 82
- Locations
- 2
- Primary Endpoint
- Platelet reactivity at physical rest: EC50 of TRAP-6 in terms of platelet CD62P expression. Unit of Measure: µM (Micromolar)
Study Overview
Brief Summary
The purpose of this study is to determine whether high intensity interval training (INT) is more effective in suppressing platelet reactivity than continuous, moderate intensity training (CONT) in patients undergoing cardiac rehabilitation after percutaneous coronary intervention.
Detailed Description
Background: Platelets play an important role in cardiovascular disease: First, they promote the development of atherosclerotic lesions, and second, platelets form vessel occluding thrombi on top of (ruptured) lesions, ultimately leading to thrombotic events like myocardial infarctions (MCI). Whereas acute, strenuous exercise causes platelet activation and transiently increases the risk for MCIs, long-term chronic exercise training results in a clear reduction of both platelet activation and MCI incidence.
Exercise training plays a key role in cardiac rehabilitation, since improvements in cardiorespiratory fitness (CRF) are associated with decreased mortality in these patients. With respect to CRF improvements, high-intensity interval training has been demonstrated to be more effective than moderate-intensity continuous exercise. However, the beneficial effect of high-intensity interval training on platelet function in patients with cardiovascular disease has never been investigated.
Scientific question: The aim of this study is to determine the effect of interval training in cardiac rehabilitation on platelet function.
Hypotheses: Cardiac rehabilitation with interval training components (INT) reduces
- platelet activation and platelet reactivity at physical rest
- changes of platelet activation and -reactivity induced by acute, strenuous exercise to a greater extent than cardiac rehabilitation consisting exclusively of moderate-intensity continuous exercise training (CONT).
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- None
Eligibility Criteria
- Ages
- 45 Years to — (Adult, Older Adult)
- Sex
- Male
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •No regular exercise training within the last 6 months
- •Dual anti-platelet therapy (low-dose aspirin plus ADP(adenosine diphosphate)-receptor antagonist)
- •Status post percutaneous coronary intervention after recent acute coronary syndrome as underlying reason for current rehabilitation
- •Eligibility for outpatient cardiac rehabilitation according to Table I in Niebauer et al. 2013 (PMID: 22508693)
Exclusion Criteria
- •Type II diabetes mellitus
- •Aortic aneurysm / dissection
- •Uncontrolled hypertension (>180/110 mmHg)
- •Pulmonary hypertension (>55 mmHg)
- •Previously known hereditary platelet disorders
- •Disorders of plasmatic coagulation
- •Anemia (Hb < 13g/dl)
- •History of end-stage liver or kidney disease
Arms & Interventions
Interval
2x / week INT
2x / week CONT
Intervention: INT (Behavioral)
Interval
2x / week INT
2x / week CONT
Intervention: CONT (Behavioral)
Continuous
4x / week CONT
Intervention: CONT (Behavioral)
Outcomes
Primary Outcomes
Platelet reactivity at physical rest: EC50 of TRAP-6 in terms of platelet CD62P expression. Unit of Measure: µM (Micromolar)
Time Frame: 6 weeks
Platelet reactivity as measured by half maximal effective concentration (EC50) of the platelet agonist TRAP-6 (Thrombin receptor activating peptide-6; SFLLRN) in terms of platelet CD62P (P-selectin) expression, as described in Heber et al. 2016 (PMID: 26909532). The percentage of CD62P expressing platelets is quantified by flow cytometry without and with increasing concentrations of the platelet agonist TRAP-6. EC50 of TRAP-6 is estimated by fitting a four parameter logistic dose-response curve to flow cytometry data as a function of agonist concentration, aggregating multiple measurements to one reported value (EC50) with the unit µM. Treatment effects on platelet reactivity at physical rest after 6 weeks (INT vs. CONT) are estimated by ANCOVA, with baseline values as covariate.
Secondary Outcomes
- Platelet reactivity at physical rest: EC50 of TRAP-6 in terms of platelet CD62P expression. Unit of Measure: µM(12 weeks)
- Cardiorespiratory fitness: Maximal power output(12 weeks)
- Cardiorespiratory fitness: Maximal oxygen consumption(12 weeks)
Investigators
Stefan Heber
Dr. Med. Univ.
Medical University of Vienna