History of Heart Block "Stokes- Adams Disease" Introductory Note to a Classic Article by Prof. William Osler, M.D., F.R.S.

Our understanding of heart block began in Padua, Italy, about 250 years ago with John Baptist Mor- gagni, the father of pathological anatomy. In 1761, Morgagni provided the first clinical description of what he called apoplexy or epilepsy.' Additional clinical-pathological findings were provided in case descriptions by two Irish physicians, Mr. Robert Adams, a surgeon, in 1827,2 and Dr. William Stokes, a physician, in 1846.3 The electrophysiolog- ical features of heart block were first described by Gaskell in his classic work on the innervation of the heart.4 Additional insight into the anatomy and physiology of the conducting system and its rela- tion to heart block resulted from the work of Tawara, Keith, and Bachmann, to name but a few of the major contributors from a century ago.

The accompanying classic article by Professor William Osler entitled "Stokes-Adams Disease" provides a brief overview of the history and no- menclature of heart block. This article by Osler was published as a chapter in a textbook entitled "A System of Medicine by Many Writers" (1909) and was the direct outgrowth of a thorough, full-length article on heart block published by Osler in Lancet in 1903.5 It should be noted that the publication of this definitive work by Osler was in the same year that Einthoven reported the development of the human electrocardiogram.6

The full clinical, electrocardiographic, and pathological features of the Morgagni-Adams- Stokes syndrome (MAS if we want to make an analogy with the WPW abbreviation for the Wolff- Parkinson-White syndrome) were elucidated dur- ing the past century. The warning signs of hemi- block conduction disturbances, e.g. , right bundle

branch block with left-axis deviation or left bundle branch block, as precursors of complete heart block and associated syncope were identified in the 1960s when pacemaker therapy for this syndrome became available. The molecular genetic underpin- ning for one form of progressive conduction system degeneration recently was identified.?

It should not be forgotten that our understanding of this infrequent conduction system disorder had its beginning in a series of carefully described pa- tients with syncope. Subsequent investigations have elucidated the role of the conducting system in health and disease. As Harvey wrote in 1657, "the best way to advance the proper practice of medicine is to give our minds to the discovery of the usual form of nature by careful investigation of the rarer forms of disease."

Arthur J. MOSS, MD Rochester, NY

REFERENCES 1. Morgagni, JB. The Seats and Causes ofDiseases. 1761. English

translation by Benjamin Alexander. London, 1769. 2. Adams, R. Cases of diseases of the heart, accompanied with

pathological observations. Dublin Hospital Reports 1827;4: 353-453.

3. Stokes W. Observations on some cases of permanently slow pulse. Dublin Quarterly J Med Sci 1846;2:73-85.

4. Gaskell WH. On the innervation of the heart. J Physiol

5. Osler W. On the so-called Stokes-Adams disease [slow pulse with syncopal attacks, etc.). The Lancet 1903;l-80.

6. Einthoven W. The galvanometric registration of the human electrocardiogram, likewise a review of the use of the capil- lary-electrometer in physiology. Arch f.d. Gen Physiol 1903;

7. Tan HL, Bink-Boelkens MT, Bezzina CR, et al. A sodium- channel mutation causes isolated cardiac conduction disease. Nature 2001;409: 1043-1047.

1881;4:43-127.

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Address for reprints: Arthur .I. Moss, M.D., Box 653, University of Rochester Medical Center, Rochester, NY 14642 Fax: (716) 273-5284.

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