Cardiac MRI

MRI uses a very powerful and specialized magnet. The process works by taking advantage of the magnet property, radio waves and a very advanced computer system to image any body part.

CMR uses the same MRI machinery but is equipped with specialized cardiac specific software and hardware equipment that allows us to track the heart as it pumps. Three of our MRI scanners are equipped with appropriate software to perform CMR studies of the heart. In 2014, we will have available the most advanced MRI scanners that will provide unmatched, cutting-edge heart scans.

With the aid of magnetic resonance angiography (MRA), an intravenous contrast agent and state-of-the-art software, physicians are able to create 3-D videos of the heart noninvasively and without exposing the patient to radiation. The video shown to the right was created with an MRA of a patient with Tetralogy of Fallot (TOF). The video highlights the vessels that feed the lung (pulmonary arteries as shown in blue) as well as an enlargement of the right heart chamber (connected to the pulmonary artery). The patient successfully underwent pulmonary valve replacement surgery shortly after the cardiac MRI scan. The added value of cardiac MRI is the ability to quantitatively assess not only how leaky the pulmonary valve is, but also the impact on the heart’s ability to squeeze (ejection fraction) and how large the chamber has become.

CMR scans are usually performed in older children, adolescents and adults with acquired or congenital heart disease. These patients typically require additional information that cannot be provided by other procedures such as ultrasound. For most routine CMR scans, you or your child will remain awake and interact closely with our CMR technologist and doctors with expertise in CMR and heart disease. For younger children, your doctor may need additional information not available by other non-invasive methods.

If your doctor needs additional information beyond what can be provided by echocardiography, to either determine how your heart is doing, your response to medications or to obtain information prior to a heart catheterization or surgery, a cardiac MRI will provide a better roadmap for your doctor to ensure the best chance of success. If you or your child has been told you will need a CMR scan, your doctor will work with Nationwide Children's Hospital to schedule an appointment. You will then be contacted by your doctor’s office to coordinate your appointment. Our team will pre-certify the requested scan so you do not have to. Once you have an appointment scheduled, a member of the Advanced Cardiac Imaging team will contact you and provide instructions on what type of clothing to wear along with what time to arrive.

You can expect to arrive 45-60 minutes prior to your appointment to allow time for registration and to answer any questions you may have. We encourage you to discuss the upcoming scans with your child as it will help them prepare better. On the day of the scan, your child can receive a topical anesthetic applied to potential IV sites to significantly reduce any pain during placement of the IV. The technologist will answer any additional questions you have and will perform a safety check with you and your child. You and your child will be asked a series of safety questions and you will be asked to remove any jewelry, rubber bands and any metal products (especially on toys) in addition to safety instructions.

Once an IV has been placed and our safety check has been performed, you and your child will be escorted to the CMR scanner, which is a large magnet. Parents are welcome to stay in the room or near your child if you wish. You and your child should know that although the magnet makes a lot of loud noise, once you cleared by our safety team you will be safe. Monitoring and scanning coils will be placed on your child's chest, and your child will be given breathing instructions to not only improve the quality of the study, but to improve the outcome of the scan.

Unless you are pregnant, parents can be in the CMR room during your child's scan. The machine is really loud, so both you and your child will wear earplugs (or a special noise reducing headphone) to protect your hearing. If you need to see your primary care physician that day, we will communicate the results to them directly so you have the most up-to-date information regarding how well the heart is doing. Should you or your child be interested in seeing the images, the cardiologist can go over the study with you. The results are typically available to your doctor within 24-48 hours, but for complex patients, it may take longer. However, if our cardiologist is available, you may be able to review the images together and be provided with preliminary information.

During the scan, your child will have direct communication with the technologist, cardiologist and radiologist. Since we need to see the image of the heart, and it is constantly pumping, there will be some electrocardiogram leads placed on the chest to allow us to follow the heart rate. Your child and/or you will sit on a gurney that moves the child's body into the opening of the magnet. During the scan, the body part that needs to be scanned will be placed in the center of the magnet, so the table position will move periodically. Once cleared by our CMR safety team, and while in the scanner, nothing that he or she touches will cause any harm. Once we start taking pictures of your child’s heart, you or your child may hear a loud knocking noise from the scanner. It is important to inform your child that when he or she hears the knocking, they should hold very still and listen for breathing instructions from our CMR technologist. If your child is unable to hold still, you will need to reschedule the scan for a future date so they can be placed under anesthesia. Once the scan has been completed, your child will lay on the table for a couple of minutes. At that time, the IV will be removed.

Yes, most people will remain awake listening to music or watching a movie while interacting with the CMR technologist, who will be giving breathing instructions to the patient. If you or your child enjoys music, or would like to watch a movie, we encourage you to bring them to your appointment. We do offer a wide selection of music and movies for you to choose from as well. For those who are not able to lay still due to age or other reasons, your CMR scan may be performed with the assistance of the anesthesiologist, who may give some medication to help the patient calm down. They may even need to give medication to help the patient sleep and provide a breathing tube.

In most cases, the actual scan time will take 45-75 minutes depending how well you or your child can hold your breath. Sometimes, it can take up to 2 hours. This is in addition to arriving 45-60 minutes before your scheduled scan. In total, from the time you arrive for registration, get the appropriate safety check, have an IV placed and have your CMR scan performed, plan to be here for 2-3 hours. Sometimes it may take longer if we have emergency cases or if the patient before your appointment is delayed.

We encourage you to arrive at or before your designated time.

Pain is significantly reduced with topical anesthetic applied 30-45 minutes before the IV is placed. Besides the actual IV placement, there is no pain expected before, during or after the CMR scan. We will do everything possible to make the experience as painless and as safe as possible.

Your child may receive a contrast agent if your doctor and the CMR team decide to perform a cardiac magnetic resonance angiography for external vascular anatomy, for myocardial perfusion or fibrosis imaging, which is typically given towards the end of the scan. If your child is to receive contrast, they will need an intravenous catheter (IV) placed prior to the scan by one of our highly-skilled technologists or nurses. Depending on your child’s disease and what we are looking for, your child will receive one of two pharmacy-approved contrast agents. As long as your child's kidney function is normal and there is no known allergy to the medication, there is no difference in the risk between the two contrast agents. It is important that you and your doctor know that your kidney function is normal prior to receiving the contrast agent. Both contrast agents add tremendous value to the CMR scan with relatively low side effects in most patients. If your child has significant kidney disease, we will still be able to perform the CMR scan, but we won't use the contrast agent.

We have a very strict safety culture here at Nationwide Children’s Hospital, and we make every effort possible to make sure you and your child are safe during the CMR scan. Our CMR team will perform safety checks with you, and once you are clear, the CMR scan does not cause any harm.

One of the major benefits of a CMR scan is that it is performed non-invasively without exposure to any radiation and, for most patients, without the need for sedation.

The collaboration between a cardiologist and a radiologist brings the unique expertise from each area. The cardiologist will know everything about the heart and knows exactly what your doctor wants to see. Together, with the radiologist, it will help your doctor choose the best sequence to perform to increase the efficiency of the scan in the safest and most accurate way possible. In addition, the radiologist provides expertise on other body parts beyond the heart. This allows us to treat you as a whole patient and not solely the disease of a specific organ. The two areas, working together as one, provides you with expertise that cannot be matched by a cardiologist or radiologist performing the study individually, especially when dealing with very complex heart disease.