Matters of the heart are often confusing. Early scientists wondered if “the motion of the heart was only to be comprehended by God” . The heart and blood were the subjects of much medical debate in the 17th century when an English physician questioned classic anatomical texts. Although previous anatomists like Vesalius had questioned traditional views, William Harvey was the first to accurately describe the circulation of blood throughout the body. Once scientists understood the regular functions of the cardiovascular system, medical pioneers explored how to manipulate the flow of blood. These later discoveries saved patients from deaths caused by conditions from surgical shock to heart disease.
Galen and Vesalius: Early Circulatory Notions
Until William Harvey’s findings were published in 1628, Galen’s work from centuries before remained the central physiological understanding of the motions of the heart and blood [1,2]. Galen taught that venous and arterial blood flowed as two different systems [3,4]. The liver was thought to produce the venous blood. In a separate system, the heart produced arterial blood and ‘spirits’ that provided heat and life to the rest of the body. According to Galen, the lungs were mainly responsible for cooling this vital blood.
Much of Galen’s experimentation was on non-human animals, and thus his descriptions were understandably flawed . For example, he described the heart as a two chambered organ divided by a septum containing invisible pores. These pores supposedly allowed blood to pass from the right to left chambers.
Despite the errors in this model, later anatomists who performed human dissections supported Galen’s description of the human heart. For example, Vesalius supported this position in the first edition of De Humani Corporus Fabrica (On the Fabric of the Human Body) in 1543, but later revised his position in the 1555 edition. In breaking with Galen’s teachings, Vesalius rejected the invisible pores without explaining how else blood could move from the right to left in the heart [3,4].
William Harvey and the “Circular Motion of the Blood”
Dr. William Harvey first voiced his views as a lecturing at London’s College of Physicians in 1616 . Two years later, he was appointed “Physician Extraordinary” to King James I. Because the potential controvery, On the Motion of the Heart and Blood in Animals (Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus) was first published in Latin at a small printer in Frankfurt in 1628.
This work clearly detailed how blood moved from the right side of the heart, through the lungs, and then to the left chambers. He further showed that blood flowed through the arteries to the veins and back to the heart – confuting the notion of two different circulatory systems.
Harvey’s treatise included mention of how knowledge of the circulatory system could be used by physicians and surgeons when applying ligatures for amputations and bloodletting. He even suggested that the circulation of the blood could explain how medicines applied to the skin enter into the blood stream!
Despite Harvey’s clarity and prominent medical career, his research was not immediately recognized in England, and his book was only published in English twenty-five years after the first edition . The 1628 and 1653 editions of On the Motion of the Heart and Blood in Animals can be found among the rare books of the Dittrick Medical History Center.
Marvels, Mavericks, and Medicine: Cardiovascular Cleveland
Harvey’s accurate account of the flow of blood allowed later physicians to therapeutically alter the circulatory system. In an upcoming talk, Dr. Brandy Schillace, Research Associate and Guest Editor of the Dittrick Museum, will discuss some of medicine’s greatest breakthroughs that occurred in Cleveland, Ohio, where pioneering physicians made history using their understandings of the motions of the heart and blood.
George W. Crile, Sr., a founding member of the Cleveland Clinic Foundation, is notable for pioneering techniques in blood transfusion. Crile was interested in preventing shock from major blood loss during surgery . On August 6, 1906, Crile saved a young man during surgery by using the patient’s brother as a blood donor . Working with silk thread and a sewing needle, Crile sutured a vein in the wrist of each man together. Upon receiving the donor blood, the patient miraculously improved in color and gained consciousness. After making improving the method, Crile used blood transfusions during WWI to triage wounded soldiers .
In 1967, Dr. René Favaloro, a young Argetine cardiovascular surgeon at the Cleveland Clinic became known as a pioneer of coronary bypass surgery in the treatment of heart disease . This technique was used to regain blood flow to heart tissues after a blockage caused by heart attacks. Favaloro and his team performed many variations of bypass surgery using a section of a vein from the patient’s leg to avoid the blocked portion of a coronary artery . From their research, these mavericks of medicine concluded that their surgery, if preformed immediately after a heart attack, could save most of the heart issue .
From William Harvey’s descriptions of the circulatory system to later discoveries, the heart and blood remain central foci of medical study and exploration. These innovations have been used to save countless lives, such that the question now is not if “the motion of the heart was only to be comprehended by God,” but instead what more can be done by harnessing this knowledge?
For more on Marvels, Mavericks, and Medicine, Dr. Brandy Schillace will be speaking at Belt Magazine’s Happy Dog University on Tuesday, June 10th at 7:30 pm.
 Harvey, William. 1628. “On the Motions of the Hearth and Blood” p. 3-75. In The Works of William Harvey, M.D. 1847 Edition. Robert Willis, trans. London.
 Willis, Robert. 1847. “A Life of the Author” p. xv-xxxiv. In The Works of William Harvey, M.D. London.
 Payne, Joseph Frank. 1896. “The Problem of Circulation” p. 35-36. In Harvey and Galen. London: Oxford University Press Warehouse.
 Pagel, Walter. 1967. William Harvey’s Biological Ideas: Selected Aspects and Historical Background. Switzerland: Basler Druck-und Verlagsanstalt.
 Loop, Floyd D. 1993. Dr. George W. Crile: The father of physiologic surgery. Cleveland Clinic Journal of Medicine. 60(1): 75-80.
 Nathoo, Narendra. Frederick K. Lautzenheiser, Gene H. Barnett. 2009. The first direct human blood transfusion: The forogotten legacy of George W. Crile. Neurosurgery. 64(3): 20-26.
 Fuster, Valentin and James T. Willerson. 2001. In memorian: René G. Favaloro, MD: The passing of a pioneer. Circulation. 103: 480-481.
 Captur, Gabriella. 2004. Memento for René Favaloro. Texas Heart Institute Journal. 31(1): 47-60.