Heart Motu Cordis" (1628) by the English physician William Harvey. Harvey's book completely describes the systemic circulation and the mechanical force of the heart, leading to an overhaul of the Galenic doctrines. Otto Frank (1865–1944) was a German physiologist; among his many published works are detailed studies of this important heart relationship. Ernest Starling (1866–1927) was an important English physiologist who also studied the heart. Although they worked largely independently, their combined efforts and similar conclusions have been recognized in the name "Frank–Starling mechanism". Although Purkinje fibers and the bundle of His were discovered as early as the 19th century, their
Science and inventions of Leonardo da Vinci scientific representation of the fetus in the intrautero. Leonardo studied the vascular system and drew a dissected heart in detail. He correctly worked out how heart valves ebb the flow of blood yet he did not fully understand circulation as he believed that blood was pumped to the muscles where it was consumed. In 2005 a UK heart surgeon, Francis Wells, from Papworth Hospital Cambridge, pioneered repair to damaged hearts, using Leonardo's depiction of the opening phase of the mitral valve to operate without changing its diameter allowing an individual to recover more quickly. Wells said "Leonardo had a depth