Cardiac MRI examination
Cardiovascular magnetic resonance (MR) examination uses a strong magnetic field, radio frequency waves, and a high-performance computer to take highly detailed still and moving images of different parts of the heart (heart chambers, heart valves, myocardium, pericardium) and its surroundings. During the examination, several images are taken from different angles of the heart as well as of the vessels entering and leaving the heart. Recorded images can be used to see and measure heart function and how blood flows through blood vessels and heart valves. This advanced diagnostic technology can provide detailed information about the types and severity of each heart disease.
When is it necessary to have the examination performed?
Your cardiologist may order a cardiac MRI if you have or are at risk for one of the following heart conditions:
- heart failure
- myocardial damage caused by previous myocardial infarction
- myocarditis
- pericarditis
- congenital heart disease
- heart valve problem
- myocardial disease or tumour
- other bulky lesions within the heart.
Cardiac MRI may be useful in making an accurate diagnosis of myocardial thickening, dilated right ventricle, or decreased left ventricular pump function. It is also the first examination that should be chosen in case of patients who need regular follow-up due to a dilated aorta (main artery).
A referral is not required to perform the scan, however, if you have any complaints, always consult a cardiologist before the examination, who will recommend the examination method that best suits your complaint.
What happens during a cardiac MRI scan?
During the cardiac MRI examination, the patient lies on his back on a movable examination table which is part of the MRI device. We place a pillow under your head and another one under your legs so that you lie comfortably. After the ECG electrodes are attached to your chest with pawls, a special receiver (coil) is placed on your chest. The examination table then slides inside the MRI device, which is a tube open at both ends.
During the examination, earmuffs are provided to reduce the operating noise of the MRI device. Communication with the MRI operator is ensured throughout.
For an accurate and measurable result, it is very important that you lie still during the scan. You will receive breathing instructions while taking the images, which means that our operator will ask you to hold your breath for a while at certain intervals.Most patients require the administration of a contrast agent because a contrast examination can provide very important additional information about the heart and blood vessels. The contrast agent can be used to locate infarct scars, determine myocardial viability, see connective tissue degeneration in already happened myocarditis, various myocardial diseases or storage disorders, as well as when examining cardiac tumours and the pericardium.
The price of the examination includes the price of the contrast agent, during the basic examination protocol, in addition to the native images, we also make images with contrast agent.
Contrast agent is not given in two cases:
- poor renal function (GFR <30)
- at the request of the patient
Although a non-contrast (native) cardiac MRI scan can provide useful information, it has several advantages over other imaging procedures, but it should be noted that important information can be lost during a native scan, which can only be replaced by a repeated examination wit contrast agent.
In case of cardiac MRI, we use a gadolinium-based contrast agent that is administered to the body by the operator with a venous injection. In most cases, contrast injection has no perceptible effect on the subject. If you are breast feeding, contrast agent manufacturers recommend that you stop breast-feeding your baby for at least 24 hours after the injection
How do I prepare for a cardiac MRI scan?
- Before entering the examination room, all metal objects (keys, jewellery, watches, coins) should be removed and all clothing with a metal zipper or other metallic material should be replaced with comfortable pyjamas or a robe for the duration of the scan.
- All electronic objects (mobile phones) and credit cards must be removed as they can be easily destroyed in the strong magnetic field.
- Do not eat for two hours before an examination with contrast agent, as nausea/vomiting may occur due to a very rare contrast allergy. At the same time, the patient can safely drink fluids and take their medications
- The examination time is 1.5 hours
When can the examination not be performed?
We cannot perform the scan in the following cases:
- Patients who have most types of implanted pacemakers or defibrillators (ICD)
- Metal surgical buckles (cerebral aneurysm vascular clips) within the head
- Certain types of inner ear implants
- Metal particles in the eye or skull
- If there are metals implanted in the patient due to previous surgeries, consultation is required prior to the examination
The MRI device uses a very strong magnetic field, which can partly damage the operation of the pacemaker or defibrillator and partly move everything that is metal.
With chest wiring suture, metal implants used to fix bone fractures, artificial joints, coronary stents, and most artificial valves, the MRI scan is completely safe, but we check the actual implant before the examination.
Other factors complicating the examination
Claustrophobia
During the MRI examination, the machine lifts the subject into a closed, narrow tunnel. This can make people feel uncomfortable and confined. Medicover uses a closed but extremely short tube device that is 10 centimetres wider in diameter than the average, so if you are claustrophobic, chances are we can examine you.
Arrhythmias
If you have an arrhythmia (atrial fibrillation, very common extrasystoles) during the scan, the quality of the test is likely to be worse, so its value is limited.
MRI contrast agent
The MRI contrast agent is removed from the body by the kidneys into the urine. People with reduced kidney function (called kidney failure) are unable to remove the contrast agent from the circulation, which very rarely can lead to a disease called Nephrogenic Systemic Fibrosis (NSF).
NSF can lead to scarring and thickening of the skin in different parts of the body. For this reason, we will need a recent (within 1 month) kidney function value (GFR) before the examination because no gadolinium contrast agent can be given below a certain cut-off value.
Possible effects of MRI
Although the MRI scan is safe, it has no harmful effects on the human body according to the current state of science, however, in the first trimester of pregnancy, the scan may cause harm to the foetus, so we try to avoid it in such cases. If the scan is not clinically urgent, you may want to wait with it after giving birth.
Are there any side effects?
- Unlike CT, MRI does not involve radiation exposure (a safer alternative for pregnant women after the first trimester)
- The risk of an allergic reaction is minimal when using a gadolinium-based contrast agent. These reactions are usually mild. Our experienced MRI operator is always available to provide immediate assistance to the patient in such cases.
When is the result expected?
The completed recording is reviewed by a cardiologist. The result will be available in our online system after 10 working days.