Magnetic Resonance Imaging for Evaluating Kidney Function

This study has been completed.
Sponsor:
Information provided by:
National Institutes of Health Clinical Center (CC)
ClinicalTrials.gov Identifier:
NCT00006173
First received: August 11, 2000
Last updated: March 3, 2008
Last verified: January 2004
  Purpose

Renovascular hypertension (RVH) is a potentially curable disease affecting 0.5-5 percent of patients with hypertension. The current diagnostic work-up of RVH involves a complex algorithm which includes doppler ultrasound, captopril renography and conventional angiography. Because of the expense, risk and inconvenience of this workup, patients may not be correctly diagnosed.

Advances in MR technology present the opportunity to develop a single comprehensive test. This would combine an MR angiogram that provides anatomic information about the renal arteries, and an MR renogram that provides information about the functional impact of a stenosis as a cause of hypertension. Our main purpose is to test MR renography with and without an oral angiotensin converting enzyme inhibitor (ACEI) combined with MR angiography against the reference standard of captopril radionuclide renography. Secondary goals of this study are to test whether hypoxia within ischemic kidneys affected by RVH is detectable by T2 weighted (Blood oxygen level dependent or BOLD) MRI. This is considered of value since such a test of oxygenation would further shorten and simplify the diagnostic MR test. Information gained from this study could lead to important changes in the diagnostic and pathophysiologic understanding of RVH.


Condition
Healthy
Renovascular Hypertension

Study Type: Observational
Official Title: Assessment of Renal Artery Stenosis and Renovascular Hypertension by Contrast Enhanced Magnetic Resonance Imaging: A Pilot Study

Resource links provided by NLM:


Further study details as provided by National Institutes of Health Clinical Center (CC):

Estimated Enrollment: 40
Study Start Date: August 2000
Estimated Study Completion Date: January 2004
Detailed Description:

Renovascular hypertension (RVH) is a potentially curable disease affecting 0.5-5% of patients with hypertension. The current diagnostic work-up of RVH involves a complex algorithm which includes doppler ultrasound, captopril renography and conventional angiography. Because of the expense, risk and inconvenience of this workup, patients may not be correctly diagnosed.

Advances in MR technology present the opportunity to develop a single comprehensive test. This would combine an MR angiogram that provides anatomic information about the renal arteries, and an MR renogram that provides information about the functional impact of a stenosis as a cause of hypertension. Our main purpose is to test MR renography with and without an oral angiotensin converting enzyme inhibitor (ACEI) combined with MR angiography against the reference standard of captopril radionuclide renography. Secondary goals of this study are to test whether hypoxia within ischemic kidneys affected by RVH is detectable by T2* weighted (Blood oxygen level dependent or BOLD) MRI. This is considered of value since such a test of oxygenation would further shorten and simplify the diagnostic MR test. Information gained from this study could lead to important changes in the diagnosis and pathophysiologic understanding of RVH.

  Eligibility

Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

INCLUSION CRITERIA

Healthy volunteers or patients with significant clinical suspicion of renovascular hypertension.

Subjects able to understand the informed consent for this study.

Subjects must be able to hold their breath for 20 second intervals.

Patients must be clinically stable and be judged by their physician able to tolerate the MR study of 1.5-2 hour duration.

EXCLUSION CRITERIA

Any contraindication for MR study including: pacemaker or other implanted electronic device; cochlear implants; metal in the eye; embedded shrapnel fragments; cerebral aneurysm clips; or medical infusion pumps.

Allergy to gadolinium, iodinated contrast media, ACEIs, or sulphur-containing medication.

Patients have a hematocrit at or below 30. Severe anemia may predispose to hypotension after captopril.

Patients with hyperkalemia (plasma potassium: above 5.0 mmol/L), because of the risk of arrhythmia.

Clinically unstable patients and those unable to tolerate a 1-2 hour MR study. Examples of medical conditions that would lead to exclusion include unstable angina, dyspnea at rest, severe pain at rest, or severe back pain.

Pregnancy.

Nursing mothers.

Subjects who are claustrophobic and are unable to tolerate MR imaging.

Patients with a serum creatinine concentration above 4mg/dl.

Bilateral renal stents.

Healthy subjects must not have an abnormality detected on dipstick urinalysis, or a systolic BP above 140 mmHg or a diastolic BP above 90 mmHg on screening examination or an abnormal BUN or creatinine level in the blood.

  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 ClinicalTrials.gov identifier: NCT00006173

Locations
United States, Maryland
Warren G. Magnuson Clinical Center (CC)
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
  More Information

Publications:
ClinicalTrials.gov Identifier: NCT00006173     History of Changes
Other Study ID Numbers: 000195, 00-CC-0195
Study First Received: August 11, 2000
Last Updated: March 3, 2008
Health Authority: United States: Federal Government

Keywords provided by National Institutes of Health Clinical Center (CC):
Atherosclerosis
Hypertension
Magnetic Resonance Angiography

Additional relevant MeSH terms:
Hypertension
Hypertension, Renovascular
Renal Artery Obstruction
Vascular Diseases
Cardiovascular Diseases
Hypertension, Renal
Kidney Diseases
Urologic Diseases
Arterial Occlusive Diseases

ClinicalTrials.gov processed this record on August 19, 2014