+Cardiac muscle, or myocardium, is the specialized [Muscle](/wiki/muscle) tissue forming the walls of the [Heart](/wiki/heart). It contracts involuntarily and rhythmically, tirelessly pumping blood throughout the body to sustain life.
+## See also
+- [Heart](/wiki/heart)
+- [Circulation](/wiki/circulation)
+- [Smooth Muscle](/wiki/smooth_muscle)
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