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Updated: Aug 4, 2026
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Impact of Intracardiac Neurons on Cardiac Electrophysiology and Arrhythmogenesis in an Ex Vivo Langendorff System
Published on: May 22, 2018
Centennial of the string galvanometer and the electrocardiogram
1Krannert Institute of Cardiology, Indiana University School of Medicine, Indianapolis 46202, USA. cfisch@iupui.edu
Journal of the American College of Cardiology
|November 25, 2000
Summary
The string galvanometer revolutionized electrocardiography (ECG), enabling practical heart rhythm diagnosis and establishing a new medical field. Early pioneers like Einthoven and Wilson significantly advanced ECG theory and clinical applications.
Area of Science:
- Cardiology
- Medical History
- Biophysics
Background:
- The string galvanometer, developed by Einthoven, enabled practical electrocardiography (ECG) around 1901.
- Early research by Galvani, Mateucci, and Lippmann laid groundwork for recording bioelectrical signals.
- Waller first recorded cardiac voltage changes from the body surface using a capillary manometer.
Discussion:
- Einthoven and Lewis dominated early electrocardiography, focusing on arrhythmias until 1920.
- Wilson's contributions after 1920 significantly advanced ECG theory, waveform analysis, and lead systems.
- ECG is crucial for diagnosing ischemic heart disease and cardiac arrhythmias.
Key Insights:
- The string galvanometer transformed cardiology, creating a new medical specialty and industry.
- Historical development traces from early bioelectrical recordings to sophisticated ECG analysis.
- Key figures include Einthoven, Lewis, and Wilson, each contributing distinct advancements.
Outlook:
- Challenges in 2000 include a shortage of skilled electrocardiographers and the rise of new noninvasive procedures.
- Computer analysis of clinical ECGs shows limitations, particularly with complex arrhythmias.
- Despite limitations, the ECG remains widely accepted and vital in medical practice.
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01:18Voltmeter
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01:25Instrumentation Amplifier
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01:29Electrocardiogram
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01:28Electrocardiogram Fundamentals
Introduction
An electrocardiogram (ECG) is a diagnostic tool for identifying cardiac conditions such as arrhythmias, conduction abnormalities, and myocardial ischemia.
Definition
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Parts of an ECG
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