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Claudication: Exercise Versus Endoluminal Revascularization (CLEVER) (CLEVER)

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified April 2013 by Rhode Island Hospital.
Recruitment status was:  Active, not recruiting
National Heart, Lung, and Blood Institute (NHLBI)
Information provided by (Responsible Party):
Joselyn Cerezo, MD, Rhode Island Hospital Identifier:
First received: August 19, 2005
Last updated: April 24, 2013
Last verified: April 2013
The purpose of this study is to compare the effectiveness of aortic stent surgery versus exercise therapy in individuals with aortoiliac insufficiency.

Condition Intervention Phase
Cardiovascular Diseases
Peripheral Vascular Diseases
Device: Stent
Behavioral: Supervised Exercise Therapy
Drug: Cilostazol
Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Claudication: Exercise Versus Endoluminal Revascularization (CLEVER)

Resource links provided by NLM:

Further study details as provided by Rhode Island Hospital:

Primary Outcome Measures:
  • MWD change score [ Time Frame: Measured at 6 months ]
    Aortoiliac revascularization with stent (ST) combined with optimal medical care (OMC) improves maximum walking duration (MWD) compared to optimal medical care alone in patients with claudication and peripheral arterial disease (PAD) who are amenable to peripheral stenting

  • MWD change score [ Time Frame: Measured at 6 months ]
    Regular supervised exercise (SE) combined with optimal medical care (OMC) improves maximum walking duration compared to optimal medical care along in patients with claudication and PAD who are amenable to peripheral stenting.

  • MWD change score [ Time Frame: Measured at 6 months ]
    Aortoiliac revascularization with stent (ST) combined with optimal medical care improves maximum walking duration compared to supervised exercise (SE) combined with optimal medical care in patients with claudication and PAD who are amenable to peripheral stenting.

Secondary Outcome Measures:
  • MWD change score [ Time Frame: Measured at 18 months ]
    To evaluate the mid-term durability of any treatment effect by performing pair-wise comparison of change in MWD between baseline and 18 month time points among all three treatment groups of primary interest.

  • Free-living daily activity [ Time Frame: Measured at 6 and 18 months ]
    To assess a treatment effect on free-living daily activity levels of any treatment group, comparing baseline electronic step monitors values with those obtained at both follow up intervals (6 and 18 months)

  • Quality of Life [ Time Frame: Measured at 6 and 18 months ]
    To examine treatment effects on patient-perceived health-related quality of life (physical function) between all groups at 6 and 18 months

  • Cost-effectiveness [ Time Frame: Measured at 18 months ]
    To Examine inpatient and outpatient costs associated with the three treatment strategies, and to evaluate the relative cost-benefit by calculating incremental cost-effectiveness and cost effectiveness acceptability curves using health utility change in the denominator.

  • Cardiovascular risk factors [ Time Frame: Measured at baseline, 6 months, and 18 months ]
    To evaluate the impact of cardiovascular disease risk factors by comparing these values at baseline, 6 months, and 18 months.

  • Interaction effect [ Time Frame: Measured at 18 months ]
    To evaluate the interaction effect, if any, of gender or race on improvements in MWD, improvement in free-living daily activities, and quality-of-life.

  • Major adverse peripheral events [ Time Frame: Measured from randomization to 18 months ]
    To track major adverse peripheral events (MAPEs) associated with aortoiliac stenting and femoropopliteal endovascular intervention.

  • Major complication [ Time Frame: Measured from randomization to 18 months ]
    Rate of major complication defined as any occurrence of death, myocardial infarction, amputation of the target limb (limb treated in this study), or occurrence of critical limb ischemia or repeat target limb revascularization (TLiR).

Enrollment: 119
Study Start Date: February 2007
Estimated Study Completion Date: July 2013
Estimated Primary Completion Date: July 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: 1
Optimal Medical Care
Behavioral: Supervised Exercise Therapy
Supervised exercise therapy, three times per week
Drug: Cilostazol
Cilostazol, 100 mg twice a day
Active Comparator: 2
Optimal Medical Care and Supervised Exercise
Device: Stent
Drug: Cilostazol
Cilostazol, 100 mg twice a day
Active Comparator: 3
Optimal Medical Care and Stent
Device: Stent
Behavioral: Supervised Exercise Therapy
Supervised exercise therapy, three times per week

Detailed Description:


Peripheral arterial disease (PAD) is a major source of morbidity and mortality, particularly in older individuals. Despite its high prevalence, clinicians often fail to diagnose PAD, particularly in patients who do not have classic claudication symptoms. Even in those individuals with documented PAD, cardiac risk factors are not often aggressively treated, and only a minority of patients receive pharmacologic therapy with cilostazol. Although there is a growing body of literature demonstrating the value of exercise rehabilitation in individuals with peripheral vascular disease and claudication, exercise rehabilitation is not often prescribed as supervised exercise rehabilitation for claudication, is not reimbursed by Medicare, and is rarely covered by private insurance. Therefore, few individuals with PAD and intermittent claudication have access to supervised exercise rehabilitation.

The use of surgical intervention and stent placement to improve blood flow in patients who do not have ischemic pain at rest or limb-threatening ischemia (Fontaine class III or IV) remains controversial. There is data suggesting that patients with intermittent claudication who have had revascularization with stents have improved exercise capacity and walking times. However, the patients in the various studies often differ substantially in their clinical characteristics, and a variety of techniques were employed, including balloon angioplasty and stents, which makes it difficult to come to a definitive conclusion about the relative efficacy of stenting to improve functional performance. Additionally, to our knowledge, the combination of stent revascularization with supervised exercise rehabilitation has not been studied.


The broad objective of the study is to optimize physical functioning, increase activity levels, and reduce cardiovascular disease risk in older individuals with PAD. The specific aim of the trial is to test the primary hypothesis that aortoiliac stenting/pharmacotherapy improves maximum walking duration (MWD) better than supervised exercise rehabilitation/exercise maintenance/pharmacotherapy for those with aortoiliac artery obstruction at 6 months. Other aims are to compare these two treatment groups with two other treatment groups, optimal medical care/pharmacotherapy and combined stent plus supervised exercise rehabilitation, at 6 months, and to compare all 4 groups with regard to the following variables: MWD change score at 18 months, changes in free-living daily activity levels, patient-perceived quality of life (QoL), and cost-effectiveness. The study also will perform exploratory analyses of demographic and biochemical risk factors for atherosclerosis, including body mass index (BMI), blood pressure, lipid profile, hemoglobin Alc (HgbAlc), fibrinogen, and C-reactive protein. An estimated 252 patients (at up to 30 study sites) with aortoiliac insufficiency and intermittent claudication will be randomly divided into four groups: optimal medical care/pharmacotherapy, supervised exercise rehabilitation/maintenance/pharmacotherapy, stent/pharmacotherapy, and stent/supervised exercise rehabilitation/pharmacotherapy. Recruitment will be performed over 28 months and patients will be followed for 18 months; the total study duration will be 5 years.


Ages Eligible for Study:   40 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Subject has symptoms suggestive of intermittent claudication, such as exercise-induced pain, cramps, fatigue, or other equivalent discomfort, involving large muscle groups of the leg(s) (calf, thigh, buttocks), relieved by rest
  • Claudication score consistent with "Rose", "atypical", or "noncalf" claudication by San Diego Claudication Questionnaire
  • Positive noninvasive evaluation for significant aortoiliac PAD on the most symptomatic side(s) (bilaterally if symptoms are equal):

    • Contrast Arteriography: Contrast arteriogram showing at least 50% stenosis in the aorta, common iliac artery, or external iliac artery, OR
    • CTA or MRA: Ankle-brachial index less than or equal to 0.9 (or abnormal ankle PVR waveform at ankle if arteries are incompressible*) with at least 60% stenosis in the aorta, common iliac artery, external iliac artery, accompanied by a biphasic or monophasic Doppler wave form at the common femoral artery (loss of early diastolic flow reversal or loss of forward flow during diastole), OR
    • Duplex Ultrasound: Ankle-brachial index less than or equal to 0.9 (or abnormal ankle PVR waveform at ankle if arteries are incompressible*) with occlusion or focal doubling of peak systolic velocity in the aorta, common iliac artery, or external iliac artery, accompanied by a biphasic or monophasic Doppler wave form at the common femoral artery (loss of early diastolic flow reversal or loss of forward flow during diastole), OR
    • Vascular Noninvasive Physiologic Tests: Ankle-brachial index less than or equal to 0.9 (or abnormal ankle PVR waveform at ankle if arteries are incompressible*) with resting thigh-brachial index (thigh-BI) less than 1.1, and common femoral artery Doppler systolic acceleration time greater than 140 msec [these tests may be ordered for study screening].

      • Abnormal PVR waveform must lack augmentation at the ankle, have a delayed, rounded systolic peak, and straight or convex downslope, and must be reviewed by the core lab.

Note: MRA/CTA, and contrast arteriogram images images must be submitted to the Clinical Coordinating Center and Doppler waveform tracings to the Noninvasive Test Committee for over read pre- or post-randomization

  • Highest ankle pressure reduced by at least 25 mm Hg after exercise compared to resting pressure (or loss of previously present Doppler signal for both the posterior tibial and anterior tibial arteries immediately after exercise if arteries were incompressible) Note: The highest ankle pressure result is determined by using the higher result of either the dorsalis pedis or posterior tibial artery measurement.
  • Subject has moderate to severe claudication symptoms, defined as less than 11 minutes MWD at baseline (initial) Gardner treadmill test

Exclusion Criteria:

  • Presence of critical limb ischemia (Rutherford Grade II or III59 PAD, defined as pain at rest, ischemic ulceration, gangrene) or acute limb ischemia (pain, pallor, pulselessness, paresthesias, paralysis) in either leg
  • Common femoral artery (CFA) occlusion or greater than or equal to 50% stenosis by angiography, MRA, CTA, or duplex ultrasound or doubling of systolic velocity in the ipsilateral common femoral artery by duplex ultrasound, or 50% diameter stenosis by visual estimate in the CFA by angiography, MRA, or CTA, (inadequate outflow for iliac stent intervention), if available pre-randomization
  • Known total aortoiliac occlusion from the renal arteries to the inguinal ligaments (all other occlusions, including aortic occlusion, ARE eligible)
  • Participant has bilateral claudication symptoms and the limb that is more symptomatic does not show evidence of aortoiliac insufficiency as described in inclusion criterion number 5
  • Participant has bilateral claudication symptoms, but both limbs are equally symptomatic and one side does not show evidence of aortoiliac insufficiency as described in inclusion criterion number 5
  • Subject meets the following exclusions based upon modified American College of Sports Medicine criteria for exercise training:

    i. Ambulation limited by co-morbid condition other than claudication, for example:1. severe coronary artery disease; 2. angina pectoris; 3. chronic lung disease;4. neurological disorder such as hemiparesis;5. arthritis, or other musculoskeletal conditions including amputation ii. Poorly-controlled hypertension (SBP greater than 180 mm Hg) iii.Poorly-controlled diabetes mellitus iv. Other active significant medical problems such as cancer, known chronic renal disease (serum creatinine greater than 2.0 mg/dl within 60 days or renal replacement therapy), known chronic liver disease or anemia, active substance abuse, or known history of dementia

  • Contraindication to exercise testing according to AHA/ACC guideline, specifically: Acute myocardial infarction (within 3-5 days), unstable angina, uncontrolled cardiac arrhythmias causing symptoms or hemodynamic compromise, active endocarditis, symptomatic severe aortic stenosis, acute pulmonary embolus or pulmonary infarction, acute noncardiac disorder that may affect exercise performance or be aggravated by exercise such as infection, thyrotoxicosis, acute myocarditis or pericarditis, known physical disability that would preclude safe and adequate test performance, known thrombosis of the lower extremity, known left main coronary stenosis or its equivalent, moderate stenotic valvular heart disease, electrolyte abnormalities, known pulmonary hypertension, tachyarrhythmias or bradyarrhythmias, hypertrophic cardiomyopathy, mental impairment leading to inability to cooperate, or high degree atrioventricular block
  • Arterial insufficiency of target lesion due to restenosis of an angioplasty/stent or bypass is not eligible
  • Recent (less than 3 months) infrainguinal revascularization (surgery or endovascular intervention)
  • Recent major surgery in the last 3 months
  • Abdominal aortic aneurysm greater than 4 cm or iliac artery aneurysm greater than 1.5 cm is present
  • Patients who are pregnant, planning to become pregnant, or lactating
  • Unwilling or unable to attend regular (3 times a week) supervised exercise sessions. (Please review this commitment carefully with each prospective participant.)
  • Weight greater than 350 lbs or 159 kg (may exceed treadmill and angiography table limits)
  • Inability to understand and sign informed consent forms due to cognitive or language barriers (interpreter permitted)
  • Absolute contraindication to iodinated contrast due to prior near-fatal anaphylactoid reaction (laryngospasm, bronchospasm, cardiorespiratory collapse, or equivalent) and which would preclude patient from participation in angiographic procedures
  • Allergy to stainless steel or nitinol
  • Allergy or other intolerance to cilostazol (bleeding history) or history of congestive heart failure [if ejection fraction is shown to be greater than or equal to 50% patient may be enrolled]
  • Nonatherosclerotic cause of PAD (fibromuscular dysplasia, dissection, trauma, etc)
  • Inability to walk on a treadmill without grade at a speed of at least 2 mph for at least 2 minutes on the first treadmill test
  • ST-segment depression greater than 1 mm in any of the standard 12 ECG leads or sustained (greater than 30 seconds) arrhythmia other than tachycardia or occasional premature atrial or ventricular contractions during exercise testing
  • Post-exercise systolic blood pressure within the first five minutes after eligibility treadmill test lower than pre-exercise systolic blood pressure
  • A peak heart rate greater than 80% of maximum (calculated by subtracting age from 220) while reporting "onset" of claudication symptoms (level 3 or 4) during the second baseline examination
  • Repeat treadmill test shows a MWD result that is greater than 25% different than the subject's initial Gardner treadmill test result. Current active involvement in a supervised exercise program (e.g., with a trainer, exercise protocol, and goals, such as in cardiac or pulmonary rehabilitation) for more than 2 weeks within the prior 6 weeks.
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its identifier: NCT00132743

  Hide Study Locations
United States, California
VA Loma Linda
Loma Linda, California, United States, 92357
St. Joseph Hospital
Orange, California, United States, 92868
VA Palo Alto Health Care Systems
Palo Alto, California, United States, 94304
UC Davis
Sacramento, California, United States, 95817
Vasek Polak Research Program
Torrance, California, United States, 90505
United States, Florida
Baptist Cardiac and Vascular Institute
Miami, Florida, United States, 33176
United States, Georgia
Aiyan Diabetes Center
Evans, Georgia, United States, 30809
United States, Illinois
Northwestern Memorial Hospital
Chicago, Illinois, United States, 60611
United States, Iowa
The Iowa Clinic
Des Moines, Iowa, United States, 50309
United States, Louisiana
Rapides Regional Medical Center
Alexandria, Louisiana, United States, 71303
Ochsner Clinic
New Orleans, Louisiana, United States, 70002
United States, Maine
Maine Medical Center
Portland, Maine, United States, 04102
United States, Maryland
Johns Hopkins
Baltimore, Maryland, United States, 21287
United States, Michigan
VA Ann Arbor
Ann Arbor, Michigan, United States, 48109
Henry Ford Hospital
Detroit, Michigan, United States, 48202
United States, Minnesota
Abbott Northwestern Vascular Center
Minneapolis, Minnesota, United States, 55407
United States, New York
Stony Brook
Stony Brook, New York, United States, 11794-8191
United States, North Carolina
Asheville Cardiology
Asheville, North Carolina, United States
Forsyth-Salem Surgical
Winston Salem, North Carolina, United States, 27103
United States, Ohio
Vascular Endovascular Specialists of Ohio
Mansfield, Ohio, United States, 44907
Jobst Vascular
Toledo, Ohio, United States, 43606
United States, Oregon
Oregon Health Science University (DOTTER)
Portland, Oregon, United States, 97239
United States, Pennsylvania
University of Pennsylvania
Philadelphia, Pennsylvania, United States, 19104
United States, Rhode Island
Rhode Island Hospital
Providence, Rhode Island, United States, 02903
United States, Washington
Providence Medical Research
Spokane, Washington, United States, 99204
United States, West Virginia
Charleston Area Medical Center
Charleston, West Virginia, United States, 25304
Canada, Nova Scotia
Capital Health
Halifax, Nova Scotia, Canada, B3H 2Y9
Sponsors and Collaborators
Joselyn Cerezo, MD
National Heart, Lung, and Blood Institute (NHLBI)
Principal Investigator: Don Cutlip, MD Brigham and Women's Hospital
Principal Investigator: Timothy Murphy, MD Rhode Island Hospital
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Joselyn Cerezo, MD, Clinical Trials Project Manager, Rhode Island Hospital Identifier: NCT00132743     History of Changes
Other Study ID Numbers: 224
U01HL081656 ( US NIH Grant/Contract Award Number )
U01HL077221 ( US NIH Grant/Contract Award Number )
Study First Received: August 19, 2005
Last Updated: April 24, 2013

Additional relevant MeSH terms:
Cardiovascular Diseases
Vascular Diseases
Peripheral Vascular Diseases
Peripheral Arterial Disease
Arterial Occlusive Diseases
Bronchodilator Agents
Autonomic Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs
Anti-Asthmatic Agents
Respiratory System Agents
Fibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action
Platelet Aggregation Inhibitors
Vasodilator Agents
Neuroprotective Agents
Protective Agents
Phosphodiesterase 3 Inhibitors
Phosphodiesterase Inhibitors
Enzyme Inhibitors processed this record on May 23, 2017