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Heart MRI
Definition:
Heart magnetic resonance imaging (MRI) is a non-invasive procedure that uses powerful magnets and radio waves to produce pictures of the heart without exposure to ionizing radiation (X-rays). The heart may be scanned by itself, or a heart MRI may be part of a chest MRI. Alternative Names:
Magnetic resonance imaging - cardiac; NMR - cardiac; Nuclear magnetic resonance - cardiac; MRI of the heart Text Continues Below
How the test is performed:
MRI uses radio waves very close in frequency to those of ordinary FM radio stations, so the scanner must be located within a specially shielded room to avoid outside interference. The patient is lies on a narrow table which slides into a large tunnel-like tube within the scanner. Small devices may be placed around the head, arm, or leg, or adjacent to other areas to be studied. These are special body coils which send and receive the radio wave pulses, and are designed to improve the quality of the images. An IV may be placed in the patient's hand or forearm if contrast medium will be used. A technologist will operate the machine and observe the patient from an adjacent room during the entire study. Several sets of images are usually required, each taking from 2-15 minutes. A complete scan, depending on the sequences performed, and need for contrast enhancement may take 1 hour or more. Newer scanners may complete the process in less time. How to prepare for the test:
No preparatory tests, diets, or medications are usually needed. An MRI can be performed immediately after other imaging studies. Depending on the area of interest, the patient may be asked to fast for 4 to 6 hours prior to the scan.
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