IS Case 186: Ischemic cardiomyopathy
Imaging Sciences URMC 2008
Publication Date: 2009-05-22
Ischemic cardiomyopathy results from coronary artery disease and subsequent myocardial wall infarction. Cardiac magnetic resonance may provide evaluation of cardiac perfusion, function and viability. Function is evaluated on dynamic images, which display wall motion and chamber size throughout the cardiac cycle. Ejection fraction and other parameters are calculated from this data.
Viability is evaluated on delayed imaging with a gadolinium based contrast agent. Delayed enhancement is compatible with non-viable tissue (i.e. infracted) and is described as either subendocardial or transmural. A hypokinetic wall segment that does not enhance may be hibernating (i.e. hypoxic) and benefit from intervention. Non-ischemic cardiomyopathies demonstrate other patterns of enhancement beyond the scope of this case presentation.
For imaging evaluation, the left ventricle has traditionally been divided into seventeen segments, spiraling counterclockwise from the base to the apex (see Fig. 5).
Typically, the left anterior descending artery supplies the anterior, anteroseptal and inferoseptal segments at the base; anterior and anteroseptal segments at the mid-cavity; anterior, septal and apex segments apically.
Notably, considerable variation in these distributions exists.
Our patient has transmural infarction in the right coronary artery distribution extending from the base to the mid-cavity. Subendocardial infarction is present in the left circumflex artery distribution extending from the base to the apex.
- Bogaert J, Dysmarkowski S, Taylor AM. Clinical Cardiac MRI. Springer, 2005:173-216.