Prior to the examination, our MRI operator will inform you about the course of the examination and ask you about the existence of possible risk factors.
Then you are escorted into the examination room where they prepare you for the examination: the operator places you on the MRI examination table, inserts the cannulas for the administration of adenosine and the contrast agent, places the ECG electrodes on your chest and a cuff for measuring blood pressure on your arm. Chest shaving may be necessary in case of our male patients to apply ECG pads because good quality cardiac MRI recordings cannot be made without a good quality ECG signal.
During the scan, you will be lying on your back, and it is important that you stay still throughout so that the images are sharp. If you have any problems, you can use the emergency call to interrupt the scan at any time.
In the first stage of the examination (15-20 minutes), the heart is recorded at rest, which does not cause any discomfort, you will only hear the click of the MRI machine.
In the second stage, the heart is examined under a drug load. For a short time (5-6 minutes), an infusion pump delivers a small amount of vasodilating adenosine into the body, which has an effect on the heart similar to exercise, temporarily widening the coronary arteries, increasing blood flow to the heart and increasing heart rate. During the stress, your heart rate and blood pressure are closely monitored, and two-way communication with our colleague is provided through the microphone and headphones.
Adenosine is a very safe drug in case of well-selected patients, but with some temporary unpleasant side effects. Most people usually do not feel anything during the first half to a minute of taking adenosine and then experience the following side effects for a few minutes afterwards:
- mild heat wave, flush, sweating
- mild shortness of breath
- chest tightness / sore throat / shoulder pain
- mild headache / dizziness
- fast heartbeat
The side effects listed above may vary from individual to individual, with none or 2-3 occurring at a time.
However, these side effects disappear quickly, within half a minute, when the adenosine is stopped, because the half-life of adenosine is short, only 10 seconds, which means that the drug disappears from the patient’s body.
At the end of the stress examination, a gadolinium-based MRI contrast agent is delivered to your body to see if there are any images of the myocardium that have an area of the heart which blood supply has been reduced due to coronary stenosis. Administration of the contrast agent usually does not result in any unpleasant side effects, after the scan it is excreted through the kidneys and urine. Rarely, it may cause a mild allergic reaction in those who are sensitive to it.
In the last stage of the examination, resting images of the heart muscle are taken for an additional 15-20 minutes.
After finishing the scan, you can return to your normal lifestyle. You may feel tired after the examination, so we recommend that you have someone accompany you.