14th International Congress
THE "NEW FRONTIERS"
OF ARRHYTHMIAS 2000

Jan. 29 - Feb. 5, 2000
Marilleva, Trento, Italy

RT-7

Historical perspectives on cardiac pacing and defibrillation

Berndt Lüderitz.
Department of Medicine-Cardiology, University of Bonn, Bonn, Germany

The diagnosis and treatment of cardiac arrhythmias including cardioversion and defibrillation has a long and fascinating history. From earliest times, no clinical symptom impressed the patient (and the physician) more than an irregular heart beat. In fact, Ludwig van Beethoven (born in Bonn, Germany, December 17, 1770) set his own cardiac rhythm disturbances to music (piano sonata opus 81a “Les adieux”) long before Einthoven graphically documented the electrical expression of regular and irregular cardiac activity in the form of an electrocardiogram. Although ancient Chinese pulse theory laid the foundation for the study of arrhythmias in the fifth century B.C., the most significant breakthrough in the identification and treatment of cardiac arrhythmias first occurred in this century. In the last decades, our knowledge of pharmacology and electrophysiology has increased exponentially. The enormous clinical significance of cardiac rhythm disturbances has favored these advances. On the one hand, patients live longer and thus are more likely to experience arrhythmias. On the other hand, circulatory problems of the cardiac vessels have increased enormously, and this has been identified as the primary cause of cardiac rhythm disorders. Coronary heart disease has become not just the most significant disease of the heart, it has become the most significant disease of all, based on the statistics for cause of death in Western industrialized nations. Arrhythmias are the main complication of ischemic heart disease, and they have been directly linked to the frequently arrhythmogenic sudden death syndrome, which is now presumed to be an avoidable “electrical accident” of the heart.

TABLE I – Chronological overview of the discovery of the cardiac conduction system

Like any other field of medicine, the study of arrhythmias has a distinctive past. Our current level of knowledge is not the result of a straight, linear progression any more than there is a static, established, monolithic body of thoughts dominating this field. Instead, our knowledge of arrhythmias today is the result of many competitive, sometimes serendipitous, scientific realizations, of which a few proved useful enough to pursue and eventually led to real advancements.

A retrospective look – often charming in its own right – may not only make it easier to sort through the copious details of this field and so become oriented in this universe of important and less important facts; it may also assist the observer in a chronological vantage point of the subject. The study of arrhythmias is no dry compendium of facts and figures, but rather a dynamic field of study evolving out of the competition between various theories¹.

The discovery of the cardiac conduction system is a cornerstone of the pathophysiologically based antiarrhythmic therapy. In table I the most important scientists and their contributions are listed chronologically^3-9.

In the majority of cases, the diagnosis of cardiac rhythm disorders relies on noninvasive examinations in addition to the clinical analysis of symptoms. Vague or broadly defined symptoms may require invasive diagnostic techniques.

Electrocardiography, the basic tool for noninvasive arrhythmia diagnosis and prerequisite of antiarrhythmic therapy translates each cardiac action into a potential variation over time.

Table II – The history of electrotherapy from the 16th to the 20th century^{1, 2}

In the beginning, there is not simply the anatomy and physiology of the heart, but also analysis of the pulse, which indicates the activity of the heart (Fig. 1). The analysis of the (peripheral) pulse as a mechanical expression of heart activity goes back several millennia. In China, in the year 280, Wang Shu Ho wrote a classic treatise about the pulse. The Greeks called the pulse “sphygmos”, and the sphygmology thus deals with the theory of this natural occurence. In Roman times, Galen interpreted the various types of pulse according to the widespread presumption of the time, that each organ in each disease has its own form of pulse. Therapy for cardiac rhythm disturbances – both clinically as well as in practice – may be divided into causative therapy general measures (such as bed rest, sedation, possibly vagal stimulation, etc.), pharmacological therapy, electrotherapy especially cardioversion and defibrillation, and, in some cases, even antiarrhythmic surgical interventions. The history of electrotherapy is shown in table II.

Fig. 1: Physician's visit. Oil painting by Frans van Mieris (1635-1681).