Cardiovascular
MR imaging includes the complete anatomical display of the heart with
CINE imaging of all phases of the heartbeat. Ultrafast techniques make
breath hold three-dimensional coverage of the heart in different
cardiac axes feasible.
Cardiac MRI provides reliable anatomical and functional assessment of the heart and evaluation of myocardial viability and coronary artery disease by a noninvasive diagnostic
imaging technique.
Cardiovascular
MRI offers potential advantages over radioisotopic techniques because it provides
superior spatial resolution, does not use ionizing radiation, has no
imaging orientations constraints and
contrast resolution better than
echocardiography. It also offers direct visualization and characterization of atherosclerotic plaques and diseased vessel walls and surrounding tissues in cardiovascular research.
MRI perfusion approaches measure the alteration of regional myocardial magnetic properties after the intravenous injection of
contrast agents and assess the extent of injury after a myocardial infarction and the presence of myocardial viability with a technique based on
late enhancement. Extracellular
MRI contrast agents, like
Gd-DTPA, accumulate only in irreversibly damaged
myocardium after a time period of at least 10 minutes.
This type of patients may also have an implanted
cardiac stent, bypass or a
cardiac pacemaker and special caution should be observed on the
MRI safety and the
contraindications. While a number of coronary stents have been tested and reported to be
MRI compatible, coronary stents must be assessed on an individual basis, with the medical team weighing the risks and benefits of the
MRI procedure.
Cardiac MRI overview:
•
Calculation of ventricular volume, myocardial
mass and wall thickness
•
Functional parameters
•
Description of a stenosis or aneurysma
•
Anatomical display of the heart, vessels and the surrounding tissue