Cardiac MRI
Cardiac MRI uses a powerful magnetic field, radio waves and a computer to produce detailed pictures of the structures within and around the heart. Physicians use Cardiac MRI to detect or monitor cardiac disease. They also use it to evaluate the heart's anatomy and function in patients with both heart disease present at birth and heart diseases that develop after birth.
When are some common uses for Cardiac MRI?
- Evaluating the anatomy and function of the heart chambers, heart valves, size of and blood flow through major vessels, and the surrounding structures.
- Diagnosing a variety of cardiovascular disorders such as tumors, infections, and inflammatory conditions.
- Evaluating the effects of coronary artery disease such as limited blood flow to the heart muscle and scarring within the heart muscle after a heart attack.
- Planning a patient's treatment for cardiovascular disorders.
- Monitoring the progression of certain disorders over time.
- Evaluating the effects of surgical changes, especially in patients with congenital heart disease.
- Evaluating the anatomy and function of the heart and blood vessels in children and adults with congenital heart disease.
Additonal reasons for cardiac MRI include, but are not limited to:
- Coronary artery disease
- Evaluating the extent and recoverability of a prior myocardial infarction (heart attack)
- Diagnosing and monitoring the progression or recovery from other causes of heart failure or arrhythmia including:
- Evaluating arrhythmia or unexplained cardiogenic syncope or near sudden death
- Pericardial diseases - including masses, pericardial constriction, and certain pericardial effusions.
- Evaluating the heart valves and vessels connected to the heart, heart valve regurgitation or stenosis
- Monitoring the size of the major blood vessels (aortic aneurysms).
- Evaluating masses in or around the heart
- Used in both preoperative planning and postoperative monitoring
- Monitoring a congenital abnormality that does not yet require surgery or intervention
What are the benefits?
- MRI is an imaging technique that does not require exposure to radiation.
- MR images of the heart are better than other imaging methods for certain conditions. This advantage makes MRI an invaluable tool in early diagnosis and evaluation of certain cardiac abnormalities, especially those involving the heart muscle.
- MRI has proven valuable in diagnosing a broad range of conditions, including cardiovascular anatomical anomalies, functional abnormalities, tumors, and conditions related to coronary artery disease and cardiomyopathy.
- MR imaging can be used during certain interventional procedures, such as catheter-based ablation procedures to treat irregular heart rhythms, including atrial fibrillation. The use of MRI can substantially shorten procedure time and result in improved accuracy.
- MRI can detect abnormalities that might be obscured by bone with other imaging methods.
- Gadolinium contrast material used during MRI is less likely to cause an allergic reaction than the iodine-based contrast materials.
- Cardiac MRI evaluates the structures and function of the heart and major vessels without the risk of radiation exposure associated with other procedures or exams.
Are there any risks?
- Any medical devices implanted into your body may be at risk of malfunction due to the strong magnetic field.
- In very rare cases, in patients with poor kidney function, nephrogenic systemic fibrosis is a possible complication when contrast is used.
- Gadolinium-based contrast has a very slight risk of causing an allergic reaction which can usually be easily treated.
- Pregnant women should consult with their physician prior to an MRI exam. However, there have been no documented negative effects of MRI in the many years of its medical usage, and MRI is often the method of imaging chosen for pregnant women and fetuses. It should be noted that MRI contrast agents are not recommended to be used during pregnancy unless the benefits far outweigh the risks.
- The ACR states that current information suggests breastfeeding is safe after the use of intravenous contrast. Please discuss your breastfeeding options with your medical provider.
How should I prepare?
- Guidelines about eating and drinking before an MRI exam will vary. You will be informed of any exam preparations required during the scheduling of your exam.
- Before your MRI exam you will be asked to change into a gown; removing undergarments that may have metal fasteners or fibers.
- Jewelry and other metal objects can not be worn during the exam. Please try to leave them at home if possible.
- You must notify the technologist if you have any implanted medical devices or any metal in your body. These can interfere with the exam and can cause harm during an MRI because of the strength of the magnet.
- Inform the technologist if you are pregnant or suspect you might be pregnant