de ex:
The heart does not usually lie in a vertical plane in the body but is somewhat rotated to the left and rests on the diaphragm. The mid to apical portion of the left ventricle resting on the diaphragm is termed the inferior wall and gives it a flat contour

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In profound hyperkalemia, the heart becomes dilated and flaccid due to decreased strength of contraction (related to a decreased number of active muscle units).