cardiac muscle


: the principal involuntary-muscle tissue of the vertebrate heart made up of striated fibers joined at usually branched ends and functioning in synchronized rhythmic contraction

Examples of cardiac muscle in a Sentence

Recent Examples on the Web Muscle mass refers to the total amount of muscle in the body, including skeletal muscle mass and cardiac muscles. Andi Breitowich, Women's Health, 4 Aug. 2023 There are three main types of muscle tissue: smooth muscle lines the gut wall and organs, except the heart; cardiac muscle is striated and covers the heart; and skeletal muscle, which can be found in the arms and legs, is also striated. Lauren J. Young, Scientific American, 2 July 2023 Decreased autophagy in cardiac muscle cells results in accumulating cellular garbage that can affect their ability to contract and even cause their death. Justin Quiles, The Conversation, 8 Feb. 2023 That is, their collaterals can completely reroute the blood flow after any blockage in the coronary arteries, so there’s no cardiac muscle death. Quanta Magazine, 13 Feb. 2023 With fewer cells and less contraction, the buildup of toxic material in cardiac muscle cells can ultimately lead to heart failure. Justin Quiles, The Conversation, 8 Feb. 2023 But because the heart has its own needs too, some of those vessels form a filigree of coronary arteries that laces through the cardiac muscle. Quanta Magazine, 13 Feb. 2023 The researchers used a variety of blood tests to look for proteins that normally reside inside cardiac muscle cells but can be released into the blood when those cells get damaged. John Timmer, Ars Technica, 3 Sep. 2020 Probably due to a lack of calcium, which helps sustain cardiac muscle contraction. Dena Rifkin, Discover Magazine, 4 Dec. 2011 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'cardiac muscle.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1846, in the meaning defined above

Time Traveler
The first known use of cardiac muscle was in 1846

Dictionary Entries Near cardiac muscle

Cite this Entry

“Cardiac muscle.” Dictionary, Merriam-Webster, Accessed 28 Feb. 2024.

Medical Definition

cardiac muscle

: 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 discs, and in intact myocardial tissue is synchronized to function in contraction especially by electrical signals of extrinsic origin passing through gap junctions in the intercalated discs compare smooth muscle, striated muscle

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