Heart FailureBy Matthew Megill hroughout the ages, the heart has Why was the great b.c. Galen knew a great deal about the heart, as ev- been portrayed in poetry and on Valen- idenced by his extant writings—most notably On tine’s Day cards as an organ of the emo- Greek physician the Doctrines of Hippocrates and Plato. tions. It wasn’t until the 17th century Given Galen’s intellectual accomplishments, Tthat scientists fully understood the heart’s role in many scholars of more recent centuries have won- Galen unable to the circulatory system. dered how he failed to recognize the heart’s true Yet this physiological puzzle might have been figure out that the role in circulating the blood. From a strictly scien- solved as early as the 2nd century, by the Greek tific perspective, he could have—perhaps even physician Galen, had he not been such a staunch heart circulated should have—discovered the process of circulation. advocate of Plato’s conception of the soul. For de- He had all the required pieces of the puzzle and spite Galen’s eminence and erudition, his philo- blood throughout the could have easily conducted any of the observations FROM THE VISUAL LANGUAGE LIBRARY VICTORIAN-ERA VALENTINE sophical beliefs appear to have clouded his scientific and experiments that William Harvey used to fi- judgment. But his fallibility is not a matter for mod- body? And even nally describe the circulatory system in 1628. ern-day smugness: the story of his research into the Nevertheless, Galen failed to pursue the con- heart contains a caution that is still pertinent near- more to the point, cept of circulation or to try the simple calculations ly 2,000 years later. that brought Harvey such success many centuries Galen was probably the most respected Greek does Galen’s failure later. What was it that prevented this brilliant doctor after Hippocrates, who codified medicine’s scholar from making the logical leap to seeing blood precepts in the Hippocratic Oath in the 5th century to discern the heart’s as a reusable vehicle that transports oxygen to the cells of the body? Why did he continue to hew to Megill, who graduated from Dartmouth College with the Class of true function hold the idea of blood as a consumable fuel—like the 2000, received his degree with honors in classics. This article is wood used to stoke a fire or the water used to irri- adapted from his senior thesis, which won both the Classical As- any lessons for the gate a field? sociation of New England’s undergraduate prize and the Bronze Chalice Award of AbleMedia’s Web-based Classics Technology Many scholars feel that Galen had a philosoph- Center. It is published here with permission from AbleMedia. scientists of today? ical bias that deterred him from understanding the 34 Dartmouth Medicine Fall 2000 heart’s role in circulation. He was a devoted fol- lower of Plato and disagreed vehemently with the opposing Stoics over the nature of the soul. Indeed, his advocacy for the Platonic view led him to dis- regard many experimentally verifiable facts that might have enabled him to conceive of the heart’s circulatory function. Pieces of the puzzle Charles Harris, a professor of the medical humani- ties, in his 1973 book The Heart and the Vascular System in Ancient Greek Medicine, examines the pieces of the puzzle that Galen held: Galen knew that the heart was associated with the pulsing of the arteries. He knew that the arteries and the veins ran parallel to each other and were connected. And he knew that both contained blood, though blood of different types. Harris concludes that this infor- mation could have led Galen to an accurate un- derstanding of the heart. It is also worth noting that Galen was familiar with Erasistratus’s description of a pumping heart. Erasistratus, a 3rd-century b.c. Alexandrian, had Nevertheless, Galen failed to pursue the concept of accurately described the heart—right down to the critical role of the valves in allowing blood to flow circulation. What prevented this brilliant scholar from in only one direction through the heart’s chambers. making the logical leap to seeing blood as a reusable But Erasistratus failed to discover circulation be- cause he believed that the arteries contained pneu- vehicle that transports oxygen to the cells of the body? ma, or air. Galen, on the other hand, decisively re- futed that belief in his On Blood in the arteries. In the process, he showed that he had a more than pass- The 2nd-century physician ing familiarity with Erasistratus’s writings. So it Galen—pictured above—was seems clear that Galen not only was familiar with a brilliant scholar but had a the pump theory but embraced it himself. blind spot where the heart If Galen understood this critical concept, he was was concerned. He was not barely a heartbeat away from Harvey’s most con- vincing piece of evidence for circulation. Harvey alone, however. Even the wrote that he first considered the circulation of the great 16th-century anatomist blood when he noted how much blood is expelled Vesalius didn’t figure out the by the heart with each contraction. Over the course concept of circulation. Note of a day, he concluded, the amount totaled more Vesalius’s illustrations of the than the body’s daily intake of food by weight. With veins (left, top) and arteries the aid of some rough calculations, Harvey proved beyond doubt that the blood must be reused. From anyone make an experiment upon the arm of a (left, bottom) of the forearm; there, conceiving of the process of circulation was man,” he wrote. “Let a ligament be thrown about the absence of detail in the but a short step. Yet Galen failed to perform this the extremity and drawn as tightly as can be borne. latter betrays his lack of un- simple calculation and continued to view blood as . It will first be perceived that beyond the liga- derstanding about how the a consumable fuel for the body. ment, neither in the wrist nor anywhere else, do circulatory system worked. Harvey’s other major points serve to further im- the arteries pulse.” On the basis of these observa- plicate Galen’s bias. In his seminal publication, De tions, Harvey concluded, correctly, that blood flows motu cordis et sanguinis in animalibus (On the move- out from the heart through the arteries and back ment of the heart and blood in living creatures), Har- toward the heart through the veins. vey described how he could push a rod up a vein but was unable to push it down a vein because of the Decisive demonstrations one-way nature of the valves. Another of his ex- Harvey also demonstrated that the heart’s pump- periments was equally simple and elegant. “Now let ing action will spit blood from a cut artery. In ad- Fall 2000 Dartmouth Medicine 35 Have a heart! For centuries, the heart has served for lovers and warriors, for parsons and poets, as a shorthand way of describing emotion— from passion and courage to grief and despair. Even long after the heart’s true physiological function was understood, the fist-sized organ has continued to serve a symbolic role. Here’s a selection of references to the heart by poets through the ages. For May wol have no slogardie anyght. From every place below the skies I will arise and go now, for always night The sesoun priketh every gentil herte, The grateful song, the fervent prayer— and day And maketh hym out of his slep to sterte. The incense of the heart—may rise I hear lake water lapping with low sounds —Geoffrey Chaucer (1343–1400) To heaven, and find acceptance there. by the shore; —John Pierpont (1785–1866) While I stand on the roadway, or on the To fret thy soule with crosses and with pavements grey, cares; The heart bowed down by weight of woe I hear it in the deep heart’s core. To eate thy heart through comfortlesse To weakest hope will cling. —William Butler Yeats (1865–1939) dispaires. —Alfred Bunn (1790–1860) —Edmund Spenser (1553–1599) Ah, when to the heart of man Love works at the centre, Was it ever less than a treason And make my seated heart knock at my Heart-heaving alway; To go with the drift of things, ribs, Forth speed the strong pulses To yield with a grace to reason. Against the use of nature. Present fears To the borders of day. —Robert Frost (1874–1963) Are less than horrible imaginings. —Ralph Waldo Emerson (1803–1882) —William Shakespeare (1564–1616) There is nothing to save, now all is lost, I have you fast in my fortress, but a tiny core of stillness in the heart The heart of man is the place the Devil’s And will not let you depart, like the eye of a violet. in: But put you down into the dungeon —D.H. Lawrence (1885–1930) I feel sometimes a hell within myself. In the round-tower of my heart. —Sir Thomas Browne (1605–1682) —Henry W. Longfellow (1807–1882) I know I am but summer to your heart, And not the full four seasons of the year. Grief tears his heart, and drives him to But for the unquiet heart and brain —Edna St. Vincent Millay (1892–1950) and fro A use in measured language lies; In all the raging impotence of woe. The sad mechanic exercise My heart will laugh a little yet, if I —Alexander Pope (1688–1744) Like dull narcotics numbing pain.
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