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On a cardiac MRI report, what is meant by rest function and viability? 

On a cardiac MRI, what is meant by the terms rest function and viability?  My cardiac MRI was normal when done last year...On the second page of my report, it's broken down into 3 areas: LAD Rest Function Viability, RCA, and LCX. [Edited for brevity.]

submitted by Rich from Pittsburgh, Pennsylvania on 5/28/2013


by Texas Heart Institute cardiologist, Benjamin Y. Cheong, MD    Benjamin Y. Cheong, MD

Cardiac Magnetic Resonance Imaging (CMRI) is now considered the gold standard in the assessment of heart function (how good the heart "squeezes") as well as to detect if there is any damage to the heart, such as prior heart attack (i.e. viability study). CMRI can look at the heart in any orientation/imaging plane, and does not require radiation (like CAT scan). In expert hands, it is an excellent method for long-term follow-up of heart function.  However, CMRI is not for everyone, e.g. patients with certain pacemakers or patients with extreme claustrophobia may not be ideal candidates for CMRI. 

Regarding the report, it should be reassuring that the resting function of the heart, i.e. the squeeze of the heart, is normal.  The American Heart Association and the American College of Cardiology recommend dividing the left side of the heart (i.e. the left ventricle, one of the important chambers of the heart) into 17 segments for reporting.  From the information provided, it suggests that all of the 17 segments squeeze normally, i.e. normal left ventricular function. Furthermore, the report also indicates that there is no prior damage to the heart (normal viability).  The "LAD", "LCX" and "RCA" are the 3 main arteries which supply blood to the left side of the heart.

If there is any concern, you could contact the physician who ordered the CMRI to further review the results.

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Updated June 2013
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