The history of cardiology : an exhibition in the Wellcome Institute of the History of Medicine.
- Wellcome Institute of the History of Medicine
- Date:
- 1970
Licence: Attribution 4.0 International (CC BY 4.0)
Credit: The history of cardiology : an exhibition in the Wellcome Institute of the History of Medicine. Source: Wellcome Collection.
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![it was possible to register the electrical activity of the heart beat without open- ing the chest and exposing the heart as was generally done. Waller recorded the activity with a capillary electrometer, a difficult instrument to use, and demon- strated this to Willem Einthoven who then introduced the superior string gal- vanometer in the early 1900s. Illustrations of Einthoven's original, cumbersome apparatus, and equipment of the early 1930s and of the present day demon- strate the enormous advances in convenience. When Einthoven first published his work in full in 1903 it created immediate interest, for once the normal tracing was understood abnormal variations could be correlated with diseased conditions. One of the most notable figures was Lewis, whose first major publication on the subject (The Mechanism of the Heart Beat, 1911) was dedicated to Einthoven (and James Mackenzie, who will be mentioned below). In his preface Lewis remarks: The records in themselves constitute the most exact signs of cardiac affections which we possess. The little strips of paper imprinted by the disease itself, form permanent and unquestionable testimony of events which have occurred, and may be placed in the balance, without disquietude, while experiences of a more subjective kind fill the opposing scale. The little strips of 'disease imprinted' paper have since led to a mass of highly technical literature over problems of interpretation. A full understanding of the functioning heart, however, owed much to the work of Gaskell and Starling. The late 19th century witnessed much contro- versy over the myogenic or neurogenic spread of conduction, i.e., whether the electrical impulses were controlled by nervous tissue, or whether it was an intrinsic characteristic of the muscle. For most people, Gaskell's classic memoir of 1883, 'On the innervation of the heart with especial reference to the heart of the tortoise' (supplementing important earlier work) settled the question in favour of the myogenic theory. The tortoise heart proved much easier than the frog heart for removing the nervous tissue, and hence for studying the properties of the heart muscle. While Gaskell was carrying out his fundamental work, Sydney Ringer was reporting on the action of various electrolytes on isolated frog's heart. His paper, 'Regarding the action of hydrate of soda, hydrate of ammonia, and hydrate of potash on the ventricle of the frog's heart' (1881) contained a large number of tracings (obtained by using Roy's tonometer attached to the ventricle) recording the effects of these substances on the heart. Ringer's Solu- tion, the first to be successfully used in physiological laboratories for examining many tissues under 'normal' environment, is a solution of five salts in balanced proportions. However, the problem still remained of studying mammalian (i.e. warm blooded) hearts. The first person to overcome this difficulty was H. N. Martin, who, according to Sewall, acted on a flash of inspiration one evening. 'I could not sleep last night [said Martin] and the thought came to me that the problem of isolating the Mammalian heart might be solved by getting a return circulation through the coronary vessels'. The idea was thus developed of keeping the heart and lungs intact, and Martin perfected an experimental technique of the heart- lung preparation so that the study of the physiology of the mammalian heart](https://iiif.wellcomecollection.org/image/b20456888_0027.jp2/full/800%2C/0/default.jpg)
