Andrea Cesalpino was an Italian physician and studied under Realdo Colombo. He was professor of medicine at Pisa and physician to Pope Clement VIII. He made important contributions to the anatomy and physiology of cardiovascular system.
Andrea Cesalpino published a monograph entiltled, "Peripateticarum quaestionum libri quinque," in 1571 which covers a variety of subjects. In his observations, he underlined the difference in the structure and function between pulmonary artery and vein. He described in detail the anatomy of the aorta and vena cava and stressed the structural differences between peripheral arteries and veins. He also suggested the existence of small connecting channels between them.
Andrea Cesalpino published his second historical monograph, "Questionum Peripateticum," in 1593. In this work, he demonstrated that following the placement of a ligature on the arms, the vein below it became dilated whereas the vein above it remained empty. As Garrison and Morton have noted "the results of tying a vein and the centripetal flow in veins were first recorded in print by Cesalpino." He was the first physician to suggest that the blood flows from the vena cava to the heart, and then it travels through the pulmonary artery and veins, and finally reaches the left ventricle and the aorta.
Cesalpino conceived that the blood in the great veins (vena cava) was flowing in one direction. He, however, failed to understand that the entire blood from the venous system was drained to the heart and thought some part of the venous blood was flowing toward the arterial system based on Galenic theory of blood motion. According to Pagel, Cesalpino thought that arteries could "draw on the contents of the veins at any point in their course." Furthermore, Fye in his analysis of Cesalpino's work commented that "he did not speculate on what happened to the blood propelled into the aorta and the arteries."
Cesalpino used for the first time the term "circulation" in his monograph. The following is a brief quotation from his monograph which contains the term circulation:
"Therefore the lung draws the warm blood from the right ventricle of the heart through a vein resembling an artery [the pulmonary artery] and returns it through the venous artery [the pulmonary vein] to the left ventricle of the heart. To this circulation of the blood from the right ventricle of the heart through the lungs into the left ventricle of the same, [the findings] from dissection fully correspond...thus the whole system is beautifully ordered. Since it is necessary to have heat in the blood of the heart in order to bring about the perfection of the nutriment...blood is transmitted from the right side of the body to the left, partly through the septum and partly through the inner tissue of the lungs, for the sake of being cooled."
Several historians have mentioned that the term "circulation" did not refer in his writing to the continuous motion of blood in a closed circuit. Historian Gweneth Whitteridge wrote that "Cesalpino is not applying the word circulation to the movement of the blood in the vessels, but to the action of cooling the hot blood from the heart." It should be noted that he also mentioned that part of the blood was transmitted through the septum. Historians of medicine have, however, acknowledged that Cesalpino had a comprehensive view and exact appreciation of the blood circulation in general.
Most historians recognize that the observation of unidirectional blood flow in the great veins toward the heart was a milestone setting the stage for the accurate description of blood circulation by Harvey in 1628.
Clark ME, Nimis SA, Rochefort GR. Andreas Cesalpini: Quaestionum peripateticarum libri V, liber V, quaestio IV, J Hist Med Allied Sci 1978;33:185-213
Whitteridge G. William Harvey and the circulation of the blood. New York, American Elsevier, Inc., 1971
Pagel W. The philosophy of circles- Cesalpino-Harvey: A penultimate assessment. J Hist Med Allied Sci 1957;12;140-157
Fye WB. Profiles in cardiology: Andera Cesalpino. Clin Cardiol 1996;19:969-970