Interval Training in Cardiac Rehabilitation

August 30, 2017 updated by: Stefan Heber, Medical University of Vienna

Interval Training in Cardiac Rehabilitation: Effects on Cardiorespiratory Fitness and Platelet Function - A Randomized Controlled Trial

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.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

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

  1. platelet activation and platelet reactivity at physical rest
  2. 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).

Work program: 80 patients at the beginning of phase II cardiac rehabilitation will be randomly assigned to an interval group or to a control group. In both groups, patients will exercise 4x / week for 12 weeks. At the beginning, after 6 weeks and at the end an exercise test will be carried out. Blood will be taken before (platelet function at rest) and immediately after each exercise test (platelet function after acute, strenuous exercise). Basal platelet activation as well as platelet responsiveness towards a platelet agonist (platelet reactivity) will be analyzed.

Study Type

Interventional

Enrollment (Actual)

82

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Austria
      • Vienna, Austria, 1090
        • MUVienna

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

45 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

Male

Description

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

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Interval

2x / week INT

2x / week CONT
Behavioral: INT
  • 5 min warm-up (40% Pmax*)
  • 30 min high intensity interval training (1 min 100% Pmax, 1 min 20% Pmax, in alternating sequence)
  • 10 min cool-down (30% Pmax)

Pmax*: Maximal power output (Watt) achieved at the end of an incremental exercise test.

Other Names:
  • High intensity interval training
Behavioral: CONT
  • 5 min warm-up (40% Pmax*)
  • 30 min moderate intensity continuous training (60% Pmax)
  • 10 min cool-down (30% Pmax)

Pmax*: Maximal power output (Watt) achieved at the end of an incremental exercise test.

Other Names:
  • Moderate intensity continuous training
Active Comparator: Continuous
4x / week CONT
Behavioral: CONT
  • 5 min warm-up (40% Pmax*)
  • 30 min moderate intensity continuous training (60% Pmax)
  • 10 min cool-down (30% Pmax)

Pmax*: Maximal power output (Watt) achieved at the end of an incremental exercise test.

Other Names:
  • Moderate intensity continuous training

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
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.
6 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Platelet reactivity at physical rest: EC50 of TRAP-6 in terms of platelet CD62P expression. Unit of Measure: µM
Time Frame: 12 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. 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 12 weeks (INT vs. CONT) are estimated by ANCOVA, with baseline values as covariate.
12 weeks
Cardiorespiratory fitness: Maximal power output
Time Frame: 6 weeks
Maximal power output (Watt / kg bodyweight) at the end of an incremental exercise test
6 weeks
Cardiorespiratory fitness: Maximal power output
Time Frame: 12 weeks
Maximal power output (Watt / kg bodyweight) at the end of an incremental exercise test
12 weeks
Cardiorespiratory fitness: Maximal oxygen consumption
Time Frame: 6 weeks
Maximal oxygen consumption (ml/min/kg bodyweight) at the end of an incremental exercise test
6 weeks
Cardiorespiratory fitness: Maximal oxygen consumption
Time Frame: 12 weeks
Maximal oxygen consumption (ml/min/kg bodyweight) at the end of an incremental exercise test
12 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Medical University of Vienna

Collaborators

Medical Scientific Fund of the Mayor of Vienna
Austrian Heart Funds

Investigators

  • Principal Investigator: Stefan Heber, MD, Medical University of Vienna

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

October 1, 2015

Primary Completion (Actual)

June 14, 2017

Study Completion (Actual)

June 14, 2017

Study Registration Dates

First Submitted

October 7, 2016

First Submitted That Met QC Criteria

October 8, 2016

First Posted (Estimate)

October 12, 2016

Study Record Updates

Last Update Posted (Actual)

August 31, 2017

Last Update Submitted That Met QC Criteria

August 30, 2017

Last Verified

August 1, 2017

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • Heber 15136

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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