Editing Heart (section)

=== Ancient ===
[[File:Leonardo da vinci, Heart and its Blood Vessels.jpg|thumb|Heart and its blood vessels, by [[Leonardo da Vinci]], 15th century]]
Humans have known about the heart since ancient times, although its precise function and anatomy were not clearly understood.<ref name="USYD2016">{{cite web|title=Anatomy of the Heart|url=https://sydney.edu.au/medicine/museum/mwmuseum/index.php/Anatomy_of_the_Heart|website=University of Sydney Online Museum|access-date=2 August 2016|url-status=live|archive-url=https://web.archive.org/web/20160818202606/https://sydney.edu.au/medicine/museum/mwmuseum/index.php/Anatomy_of_the_Heart|archive-date=18 August 2016}}</ref> From the primarily religious views of earlier societies towards the heart, [[ancient Greece|ancient Greeks]] are considered to have been the primary seat of scientific understanding of the heart in the ancient world.<ref name="Anaemia2010">{{cite journal|last1=Meletis|first1=John|last2=Konstantopoulos|first2=Kostas|title=The Beliefs, Myths, and Reality Surrounding the Word Hema (Blood) from Homer to the Present|journal=Anemia|date=2010|volume=2010|pages=857657|doi=10.1155/2010/857657|pmid=21490910|pmc=3065807|doi-access=free}}</ref><ref name="Katz2008">{{cite journal|last1=Katz|first1=A. M.|title=The 'Modern' View of Heart Failure: How Did We Get Here?|journal=Circulation: Heart Failure|date=1 May 2008|volume=1|issue=1|pages=63–71|doi=10.1161/CIRCHEARTFAILURE.108.772756|pmid=19808272|doi-access=free}}</ref><ref name="Aird2011">{{cite journal|last1=Aird|first1=W.C.|title=Discovery of the cardiovascular system: from Galen to William Harvey|journal=Journal of Thrombosis and Haemostasis|date=July 2011|volume=9|pages=118–129|doi=10.1111/j.1538-7836.2011.04312.x|pmid=21781247|s2cid=12092592|doi-access=free}}</ref> [[Aristotle]] considered the heart to be the organ responsible for creating blood; [[Plato]] considered the heart as the source of circulating blood and [[Hippocrates]] noted blood circulating cyclically from the body through the heart to the lungs.<ref name=Anaemia2010 /><ref name=Aird2011 /> [[Erasistratos]] (304–250 BCE) noted the heart as a pump, causing dilation of blood vessels, and noted that arteries and veins both radiate from the heart, becoming progressively smaller with distance, although he believed they were filled with air and not blood. He also discovered the heart valves.<ref name=Anaemia2010 />

The Greek physician [[Galen]] (2nd century CE) knew blood vessels carried blood and identified venous (dark red) and arterial (brighter and thinner) blood, each with distinct and separate functions.<ref name=Anaemia2010 /> Galen, noting the heart as the hottest organ in the body, concluded that it provided heat to the body.<ref name=Aird2011 /> The heart did not pump blood around, the heart's motion sucked blood in during diastole and the blood moved by the pulsation of the arteries themselves.<ref name=Aird2011 /> Galen believed the arterial blood was created by venous blood passing from the left ventricle to the right through 'pores' between the ventricles.<ref name=USYD2016 /> Air from the lungs passed from the lungs via the pulmonary artery to the left side of the heart and created arterial blood.<ref name=Aird2011/>

These ideas went unchallenged for almost a thousand years.<ref name=USYD2016 /><ref name=Aird2011/>