PCI Alternative Using Sustained Exercise
Condition: Cardiovascular Disease
MeSH terms: Cardiovascular Diseases
Study type: Interventional

Summary: 
      Cardiovascular disease remains the leading cause of morbidity and mortality in the U.S. and
      is a major cause of disability in Veterans. Most of these deaths are due to coronary artery
      disease (CAD). The most common treatment for CAD is revascularization, an invasive procedure
      which usually involves placing a stent inside an artery that is diseased. However, exercise
      training is often overlooked because clinicians tend to focus on repairing the coronary
      circulation and the potential need for revascularization. Studies have shown that exercise
      training can be effective for patients with CAD and that it saves costs. In this study,
      invasive revascularization will be compared to a structured program of exercise training over
      one year. Comparisons will be made between groups for symptoms, coronary artery size and
      function using PET/CTA, and health care cost utilization.
    

Detailed description: 
      Despite advances in treatment options for cardiovascular disease (CVD), this condition
      remains the leading cause of morbidity and mortality in the U.S. and is a major cause of
      disability in Veterans. Percutaneous coronary intervention (PCI) is the treatment most often
      used in patients with various manifestations of coronary artery disease (CAD). While it is
      commonly assumed that PCI also reduces mortality, randomized trials have shown that PCI has
      no effect on mortality except in patients being treated for acute myocardial infarction. Over
      the last decade, the use of PCI has increased exponentially; between 1996 and 2007, the
      number of PCIs performed in the US has increased more than 4-fold, from approximately 300,000
      to more than 1.3 million yearly. During this time, PCI has accounted for 10% of the overall
      increase in Medicare expenditures. In light of the extraordinary increase in the use of this
      technology in recent years, questions have been raised regarding the cost-effectiveness of
      PCI, the extent to which PCI is overused, and whether selected patients may benefit from
      optimal medical therapy in lieu of PCI. Cost analyses have suggested that the current rate of
      increase in PCI with DES is unsustainable for the U.S. healthcare system. Given the costs
      associated with PCI, there have been recent efforts to compare outcomes and effectiveness of
      PCI against non-invasive therapy.

      There is a need to evaluate more judicious use of PCI, and to consider less costly
      interventions for at least some of the >1.3 million patients in the U.S. who undergo this
      procedure. Lifestyle intervention, including exercise training, is one option that has been
      shown to result in reduced symptoms, better exercise tolerance, improved quality of life and
      lower mortality. A growing body of data has demonstrated that exercise intervention improves
      coronary anatomy and lessens ischemia through enhanced endothelial function. While a
      significant proportion of health care expenditures are devoted to PCI and other invasive
      interventions for CVD, few health care resources are directed toward primary or secondary
      prevention. Recent studies have demonstrated that programs of cardiac rehabilitation, with
      and without implementation of intensive risk reduction, are cost effective. In part because
      of the financial interests associated with PCI, exercise and lifestyle intervention is rarely
      considered as a clinical treatment option in PCI candidates. A gap exists between the
      standard clinical treatment for CAD and the potential for non-invasive, less expensive and
      potentially more effective treatments for these patients. Previous efforts to quantify the
      effects of exercise and lifestyle intervention on coronary artery perfusion and anatomy have
      been limited to standard angiography. In recent years, improved technologies for imaging
      coronary perfusion and anatomy have been developed, which could provide important insights
      into the effects of exercise training on the heart. These include the combination of positron
      emission tomography and ultra-fast computed tomography angiography (CTA), commonly termed
      PET/CTA. PET provides information on the functional significance of anatomic stenoses by
      measuring myocardial blood flow and myocardial perfusion reserve. PET can also be used to
      evaluate coronary endothelial function by measurements of changes in myocardial blood flow in
      response to physical stimuli (i.e., cold pressor testing). The combination of CTA with PET
      also allows for improved attenuation correction. CTA, on the other hand, can noninvasively
      image the coronary arteries to determine the severity of stenosis and the amount of calcified
      and noncalcified plaque burden.

      The investigators have termed the current proposal "PCI Alternative Using Sustained Exercise"
      (PAUSE) to reflect the potential for exercise training and lifestyle intervention as
      alternative therapies in selected PCI candidates.

      Primary aim: To determine whether subjects with lesions amenable to PCI randomized to a 1
      year exercise program and lifestyle intervention have greater improvement in coronary
      perfusion and function than those randomized to PCI.

      Secondary analyses: The investigators will compare exercise test responses, health care
      costs, quality of life, and clinical outcomes between groups.
    

Intervention name(s): Exercise Therapy
Intervention type(s): Behavioral
Intervention description(s): Patients will adhere to one year of exercise therapy for the investigators' study. At minimum, subjects will aim to participate in approximately 30-60 minutes of aerobic exercise 5-7 days per week and 15-30 minutes of resistance/anaerobic exercise 2-3 times per week.
Other intervention name(s): Exercise Training
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Randomized controlled trial
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: Cardiovascular Disease; Percutaneous Intervention; coronary artery disease; exercise therapy