Heart
Learning objectives
After completing this study unit you will be able to:
- Explain the overall structure of the heart.
- Identify the layers of the heart wall in histological images.
Watch video
The heart is a hollow muscular organ with three layers. The endocardium lies inside and also forms the atrioventricular and semilunar valves. It consists of single-layered squamous epithelium (endothelium).
The myocardium, the cardiac musculature, is the thickest layer of the heart wall. It consists of striated muscles, connective tissue, blood vessels and nerve fibers. The heart muscle cells (cardiomyocytes) are connected via adhesive contacts and gap junctions (shiny stripes) and form a functional syncytium. The myocardium also contains specialized cardiomyocytes, which form the conduction system of the heart.
The epicardium envelops the heart and corresponds to the visceral sheet of the serous layer of the pericardium.
Watch the following video to learn more about the microscopic anatomy of the heart and its histological appearance:
Take a quiz
With the following quiz you can now apply and test your newly acquired knowledge:
To adjust your focus and choose the topics you’ll get quizzed on, try out our customizable quiz.
Browse atlas
:watermark(/images/watermark_5000_10percent.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/overview_image/1809/hRfJEtqSQEIKmQo9xgvA_heart-2_english.jpg){kind=logo}
Ready to review all these structures in further detail? Browse our image gallery below:
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/heart/dc5loKa5NCrT6VxFUV6cw_Heart.png "Heart (Cor); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/cardiac-muscle-4/ndqfagBai99dA20OffD4Q_Cardiac_Muscle.png "Cardiac muscle (Textus muscularis cardiacus); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/endocardium-2/bLPqz0vyO7gtDJjXcOPFQ_Endocardium.png "Endocardium; Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/endothelial-layer/2uSgjxMm1BkvXHQZF1wZg_Endothelial_layer.png "Endocardiac endothelium (Endothelium endocardiacum); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/subendothelial-layer/aEBEcjebjhs9nvrwbxs2oQ_Subendothelial_layer.png "Subendotheliac layer of endocardium (Stratum subendotheliale endocardii); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/myoelastic-layer-of-endocardium/72V4ElJxLXYIZul0TMgS6Q_Myoelastic_layer.png "Myoelastic layer of endocardium (Stratum myoelasticum endocardii); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/subendocardial-layer/rvbKzsFkRRZeXUQgSsgg_Subendocardiac_layer.png "Subendocardiac layer (Tela subendocardiaca); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/myocardium-3/6O2kFPozJbYKZnMwnrxQQ_Myocardium.png "Myocardium; Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/bundle-of-purkinje-fibers-3/6XL3K85PdAC7bLV7Oxxpg_Bundle_of_Purkinje_fibres.png "Bundle of purkinje fibers (Neurofibrae purkinjensia); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/epicardial-fat/cxn4imv0QBFOFziepK84Ig_Epicardial_Fat.png "Subepicardial connective tissue (Textus connectivus subepicardiacus); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/autonomic-nerve/6l7F8PxsvQLZVkwi650vw_Autonomic_nerve.png "Autonomic nerve (Nervus autonomicus); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/mitral-valve/DMupiYss22lHHC2wFKWi2A_Mitral_valve.png "Left atrioventricular valve (Valva atrioventricularis sinistra); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/left-atrium-5/43YYvkiTh1GK84mtjiRg_Left_atrium.png "Left atrium of heart (Atrium sinistrum cordis); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/left-ventricle-10/SI8oJR6G2hqEWG7qLGHiAw_Left_ventricle.png "Left ventricle of heart (Ventriculus sinister cordis); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/lamina-atrialis/mhEcgWDd6ei10MQlaRc6xw_Lamina_atrialis.png "Lamina atrialis of atrioventricular valve (Lamina atrialis valvae atrioventricularis); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/lamina-spongiosa/HZGlvaAiLQnBrBd8gACOvw_lamina_spongiosa.png "Lamina spongiosa of atrioventricular valve (Lamina spongiosa valvae atrioventricularis); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/lamina-fibrosa/OLO0FnqquMBeAJLmHdk5hw_Lamina_fibrosa.png "Lamina fibrosa of atrioventricular valve (Lamina fibrosa valvae atrioventricularis); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/lamina-ventricularis/byzHjp5GAnHGMhWrNfXg_Ventricularis.png "Lamina ventricularis of atrioventricular valve (Lamina ventricularis valvae atrioventricularis); Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/chordae-tendineae-5/R6J3dfVE7BK2YVOZDxUQtg_Chordae_tendineae.png "Tendinous cords of left atrioventricular valve (Chordae tendineae valvae atrioventricularis sinistrae); Image: Yousun Koh"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/anulus-fibrosus-2/P4EiIKHldTTHyKPm5dK86Q_Anulus_fibrosus.png "Anulus fibrosus; Image:"){kind=logo}
:watermark(/images/watermark_only.png,0,0,0):watermark(/images/logo_url.png,-10,-10,0):format(jpeg)/images/anatomy_term/aortic-valve-3/kcaSu3a7ufy8v0bSgrpQ_Aortic_valve.png "Aortic valve (Valva aortae); Image: Yousun Koh"){kind=logo}
Well done!
Related articles
:format(jpeg)/images/article/histology-of-the-heart/ibnbhZ4auIEvMtluIRsQ_dc5loKa5NCrT6VxFUV6cw_Heart.png)
:format(jpeg)/images/article/layers-of-the-heart/QB22WfPgTY9qdzbt38Itg_Heart_anterior_view_-_myocardium.png)
Continue your learning
Register now and grab your free ultimate anatomy study guide!
