epicardium

anatomy

Also known as: visceral pericardium, visceral serous layer

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June 26, 2026

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The epicardium is the outermost layer of the heart wall, also known as the visceral pericardium. It is a smooth, serous membrane composed of flattened epithelial cells resting on connective tissue. The epicardium is one of the three distinct layers of the heart wall, alongside the myocardium (middle layer) and the endocardium (inner layer). This layer is penetrated by coronary vessels that supply the heart with arterial blood. The epicardium is part of the pericardium, the membranous sac that encloses the heart. The pericardial fluid between the visceral and parietal layers of the serous pericardium lubricates the heart as it beats.12

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tunicate
Water/vascular system
…of the gut called the epicardium around some of the internal organs. The body cavities are considered to be a part of the circulatory system. There are a heart and some large blood vessels but no tiny capillaries. The tunicate heart is unusual in that it periodically reverses the direction…
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…of the gut called the epicardium around some of the internal organs. The body cavities are considered to be a part of the circulatory system. There are a heart and some large blood vessels but no tiny capillaries. The tunicate heart is unusual in that it periodically reverses the direction…
Read More