myocardium

(mī-ŏ-kard′ē-ŭm )

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(mī-ŏ-kard′ē-ă)
pl. myocardia [ myo- + -cardium ]
The middle layer of the walls of the heart, composed of cardiac muscle. The layers of cardiac muscle form a complex spiral. When they contract they twist or wring blood from the ventricles. The muscle layers are attached to an internal “skeleton” of the heart composed of dense connective tissue.

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