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Sir Thomas Lewis

Thomas Lewis is widely regarded as the pioneer of clinical electrocardiography and electrophysiology. Born in Cardiff, the son of a mining engineer, Lewis was initially educated at home before attending University College Cardiff. He qualified in medicine in 1905 from University College Hospital London, where he remained for the whole of his professional career. Not only was he an excellent cardiologist but also a physiologist and outstanding clinical scientist. Inspired by James Mackenzie, he was attracted to the study of cardiac arrhythmias, and in 1909 he visited Willem Einthoven, inventor of the electrocardiograph, in Leiden. Their association was to change the face of modern electrophysiology. Lewis installed the first clinical electrocardiograph in Britain.


Image References

Einthoven (left) and Thomas Lewis (right) meeting in Leiden in 1909.


The first electrocardiograph installed at University College London by Thomas Lewis.


Famous for his application of scientific methods to clinical medicine, within three years Lewis had produced his monograph “The Mechanism of the Heart Beat” in 1911 which he dedicated to James Mackenzie and Willem Einthoven. It became known as the “bible of electrocardiography”, an original copy of which is retained in the BCS archive. Lewis elucidated the nature of nearly all cardiac arrhythmias and performed detailed studies on the dog heart. Using bipolar chest leads arranged in a triangle (known as the Lewis lead), he showed that atrial flutter was due to a circus movement in the right atrium.


He introduced the term Clinical Science and founded the Medical Research Society to promote the careers of young research workers.


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Atrial flutter recorded with the Lewis apparatus. Simultaneous venous and radial pulse recordings with ECG recording of atrial flutter using the Lewis lead.


Lewis’s lecture notes.


Scrapbook of ECG recordings for teaching purposes.


Lewis’s lantern slides used for teaching purposes.


Lewis was also an inspiring teacher, promoting the importance of accurate observation and logical thinking. The historical archive contains Lewis’s teaching scrapbook, his lecture notes and the lantern slides he used in his renowned lectures. He distilled his teaching into his 1933 book “Diseases of the Heart” which was, for a while, the world’s premier cardiology textbook. The historical archive contains a large collection of Lewis’s ECG recordings.


A founding member of the Cardiac Club in 1922, Lewis was one of the most important and respected of its members. When the timing of their annual meeting changed Lewis was at risk of expulsion, having been absent for two consecutive years and thereby breaking rule 2 of the Club. A crisis was averted by the creation of an extraordinary member-ship, with Lewis as the first member. This became a precursor to the current Honorary Membership of the British Cardiovascular Society, usually only bestowed on eminent cardiologists of their generation.


Outside of medicine, Lewis was a keen ornithologist and photographer. His Dallmeyer camera and many of his original photographs form part of the Society’s historical archive.


Knighted in 1921, Lewis was made a Fellow of the Royal Society and, in 1941, received its highest honour, the Copley Medal. He died four years later of cardiac failure, having suffered two previous myocardial infarctions. He was buried in Llangasty churchyard by Llangorse Lake in the Brecon Beacons, an area where he had loved to study wildlife as a boy in Wales.


Image References

Lewis’s classic 1933 textbook “Diseases of the Heart.”


Lewis’s Dallmeyer camera.