Effects of Exercise Training on Left Ventricular Function in Type 2 Diabetic Patients Post Coronary Artery Bypass Graft

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00172536
Recruitment Status : Completed
First Posted : September 15, 2005
Last Update Posted : April 22, 2011
National Science Council, Taiwan
Information provided by:
National Taiwan University Hospital

Brief Summary:

The purpose of this study is to investigate the changes of cardiorespiratory fitness and left ventricular function in type 2 diabetes after uncomplicated coronary artery bypass graft (CABG) surgery.

We hypothesize that exercise capacity, left ventricular diastolic function, and biochemical data improves after 12-wk exercise training in patients with type 2 diabetes underwent CABG.

Condition or disease Intervention/treatment Phase
Diabetes Mellitus, Non-Insulin-Dependent Coronary Arteriosclerosis Post Coronary Artery Bypass Grafting Behavioral: Exercise training Other: Control Not Applicable

Detailed Description:

Patients with type 2 diabetes mellitus have higher incidence of coronary artery disease or left ventricular dysfunction, particularly diastolic dysfunction. Coronary artery bypass surgery is known to decrease the mortality rate in diabetes. Further exercise training can improve their cardiorespiratory fitness and the control of risk factors in these patients. However, the extent of improvement and the mechanism, especially the changes in left ventricular function, in diabetes after exercise training have not been fully explored.

Subjects will be assigned to the intervention or control group by randomization. Subjects in the intervention group will receive 60% VO2 max moderate aerobic exercise training, twice per week under supervision and three times per week at home, for 12 weeks. All subjects receive left ventricular function test by echocardiography and impedance cardiography, graded maximal exercise test, and biochemical analyses of sugar and lipid before and after 12 weeks. Their dietary intake and physical activity will be inquired every 4 weeks by questionnaires.

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 65 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double (Investigator, Outcomes Assessor)
Official Title: Effects of Exercise Training on Left Ventricular Function in Type 2 Diabetic Patients Post Coronary Artery Bypass Graft
Study Start Date : October 2004
Actual Primary Completion Date : February 2006
Actual Study Completion Date : February 2006

Resource links provided by the National Library of Medicine

Arm Intervention/treatment
Received oral general education about proper diet, regular physcial activity and other medical care if necessary
Other: Control
Subjects received general education including proper diet, regular physical activity or medical care if necessary through an interview with a physical therapist.

Experimental: Exercise training
Received a supervised structure treadmill training
Behavioral: Exercise training
Subjects attended a supervised treadmill training session three times per week in an outpatient facility for three months. Training duration was 30 minutes per session, including a 5-minute warm-up and cool-down phase. Training intensity was initially set at about 60% of HR reserve and close to the anerobic threshold (AT) and the gradually increased as tolerated.

Primary Outcome Measures :
  1. Exercise capacity [ Time Frame: Three months after the start of the intervention ]
    Exercise capacity was assessed by peak oxygen uptake (VO2peak)via exercise testing. VO2peak was measured by a metabolic measurement system (Vmax229 Metabolic Measurement System, Sensor Medics, Anaheim, CA).

  2. Diastolic heart function [ Time Frame: Three months after the start of the intervention ]
    Echocardiographic examination including color B mode TDI with a commercially available 2.5- to 3.75-MHz phased array transducer (Philips, SONOS 5500, Andover, MA)was used to evaluate diastolic function.

Secondary Outcome Measures :
  1. Endothelial function [ Time Frame: Three months after the start of the intervention ]
    Examined by flow-mediated vasodilation

  2. Hemodynamics [ Time Frame: Three times after the start of the intervention ]
    Heart rate (HR) and stroke volume (SV) were collected at rest, during the exercise test, and during the recovery phase by a noninvasive bioimpedance cardiograph device (PhysioFlow PF-05, Manatec Biomedical, Paris, France). Cardiac output (CO) and arteriovenous oxygen difference ((a-v)O2 difference) were then determined by the following equations: CO=HR*SV and (a-v)O2 difference=VO2/SV*HR

  3. Blood test [ Time Frame: Three months after the start of the intervention ]
    Including fasting glucose, HbA1c, total cholesterol (TC), high-density liporpotein (HDL-c) and triglyceride (TG).

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Ages Eligible for Study:   40 Years to 70 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • well-controlled diabetes
  • no history of myocardial infarction
  • stable post CABG for at least 3 months

Exclusion Criteria:

  • heart failure
  • valvular disease
  • abnormal kidney or liver function
  • cerebrovascular disease
  • primary pulmonary disease
  • other systemic or acute illness that may impede the testing or training

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00172536

National Taiwan University Hospital
Taipei, Taiwan, 100
Sponsors and Collaborators
National Taiwan University Hospital
National Science Council, Taiwan
Study Director: Ying-Tai Wu, Doctor National Taiwan University Hospital

Responsible Party: Ying-Tai Wu, School and Graduate Institute of Physical Therapy, College of Medicine, National Taiwan University Identifier: NCT00172536     History of Changes
Other Study ID Numbers: 9361701147
First Posted: September 15, 2005    Key Record Dates
Last Update Posted: April 22, 2011
Last Verified: March 2011

Additional relevant MeSH terms:
Diabetes Mellitus
Coronary Artery Disease
Myocardial Ischemia
Diabetes Mellitus, Type 2
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Arterial Occlusive Diseases
Vascular Diseases
Cardiovascular Diseases
Coronary Disease
Heart Diseases