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Cardiac MRI

A Cardiac MRI (magnetic resonance imaging) provides very detailed images of the heart and nearby blood vessels including:

• size
• shape
• function
• possible damage

A magnetic field and radio waves are used to create pictures and make the diagnosis of specific diseases. No radiation or x-rays are used for this test. This exam:

• requires specially trained doctors
• uses new and complex computer software
• can limit the need for more invasive testing
• The exam lasts about 60 minutes

A physician is usually present during the cardiac MRI to guide the testing and interpret images. A contrast agent is used to make certain parts of the heart and blood vessels appear brighter on the pictures. Unlike the x-ray contrast dye, the MRI contrast agent does not:

• contain iodine and is safer for the kidneys
• does not interact with most medications

However, every MRI patient needs to be screened to ensure that certain safeguards are in place. If you have any metal inside of your body, please tell your doctor before the exam. This may include:

• Heart pacemaker or implantable defibrillator (ICD)
• Aneurysm clip
• Ear or eye implant
• Joint or bone rods or clips
• Metal plate
• Bullets or shrapnel

Before the test
Before this exam, it is helpful to talk with your doctor if you cannot lie flat (for about an hour) or have claustrophobia (uncomfortable with closed-in spaces). Also, please ask your doctor if you need to make any changes in your diet before this exam. Otherwise, there is no special preparation.

Arriving at the hospital
Check in at the 4th floor reception desk in the Galter Pavilion, 251 E. Huron 30 minutes before your test time. Parking is available. Remember to bring:

• Your doctor's written order
• Insurance card
• Medicare card (Medicare patients only)

Preparing for the test

• You will be asked to complete an MRI Safety Questionnaire and a medical history form.
• Then, you will be taken to a locker room to change into a hospital gown and store your belongings. It is important that you remove all metal from your body including jewelry, credit cards, keys and dentures.
• The nurse then reviews your completed forms with you. An IV (into the vein) line is started in your arm or hand.

During the Test

• Once you are taken into the exam room, you are introduced to the technologist (tech) and the nurse who will be doing the test. They can answer any questions you may have.
• Cardiac monitoring leads, as well as a device that helps create the MRI images, will be taped to your chest. The nurse and tech will help position you comfortably on the exam table, making sure that your heart is lined up with the scanner so the proper area of your body can be examined. Then the table moves so that you are in the center of the machine.
• You will be given a set of headphones so that you will be in contact with the tech throughout the test. If medicine to relax you was ordered, it is injected into the IV at this time. During the test, you may be given an IV contrast agent (gadolinium dye). As the dye is injected, you may feel coolness at the site and may notice a slight metallic taste in your mouth. This is normal. However, please notify the staff right away if you have shortness of breath, hives or itching.
• When the scanning starts, you will hear a loud drumming noise. Between scans, the drumming noise stops. It is very important that you lie still and follow the staff's instructions once the scanning starts. You may be asked to hold your breath several times for short periods of time when pictures are taken.
• When the exam is over, you are assisted off the exam table.

After the Test

• If relaxing medicine was given into your IV line, you must remain in the department until the medicine wears off (about 45 minutes) and have a friend or family member with you to drive you home.
• Unless you are told otherwise, you may resume your normal activities and diet after the exam.
• Most often, initial findings are sent to your doctor within 48 hours. A full report follows in about five business days.