Cardiac muscle

A type of muscle with unique features only found in the heart. The cardiac muscle is the muscle of the heart and medically is called the myocardium ("myo-" being the prefix renoting muscle).

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cardiac muscle n the principal muscle tissue of the vertebrate heart that is made up of elongated striated muscle fibers each of which consists of a single cell that has an intrinsic rhythm of contraction and relaxation even when isolated, is joined physically at its often branched ends to other such cells by intercalated disks, and in intact myocardial tissue is synchronized to function in contraction esp. by electrical signals of extrinsic origin passing through gap junctions in the intercalated disks compare SMOOTH MUSCLE, STRIATED MUSCLE

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the specialized muscle of which the walls of the heart are composed. It is composed of a network of branching elongated cells (fibres) whose junctions with neighbouring cells are marked by irregular transverse bands known as intercalated discs.

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the muscle of the heart, comprising the chief component of the myocardium and lining the walls of the large vessels joined to the heart; it is composed of fibers of striated but involuntary muscle. The composition and organization of its fibers resemble those of skeletal muscle, but instead of forming a syncytium, its branched, mononucleate cells are linked end to end by intercalated disks that provide both mechanical and ionic coupling for coordination of the entire muscle. See Plate 32.