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Electrocardiogram (ECG)

Electrocardiogram Introduction

The electrocardiogram (ECG or EKG) is a diagnostic tool that measures and records the electrical activity of the heart in exquisite detail. Interpretation of these details allows diagnosis of a wide range of heart conditions. These conditions can vary from minor to life threatening.

The term electrocardiogram was introduced by Willem Einthoven in 1893 at a meeting of the Dutch Medical Society. In 1924, Einthoven received the Nobel Prize for his life's work in developing the ECG.

The ECG has evolved over the years.

  • The standard 12-lead ECG that is used throughout the world was introduced in 1942.

  • It is called a 12-lead ECG because it examines the electrical activity of the heart from 12 points of view.

  • This is necessary because no single point (or even 2 or 3 points of view) provides a complete picture of what is going on.

  • To fully understand how an ECG reveals useful information about the condition of your heart requires a basic understanding of the anatomy (that is, the structure) and physiology (that is, the function) of the heart.



Next: Basic Anatomy of the Heart »

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Electrocardiogram (ECG)

Mitral Valve Prolapse Overview

Mitral valve prolapse (MVP) is also called click-murmur syndrome, floppy mitral valve syndrome, and Barlow syndrome after the doctor who first described MVP.

The mitral valve is one of 4 valves in the heart. It opens and closes to control blood flow between the heart's left atrium and the left ventricle. The mitral valve has 2 flaps, or "leaflets."

In mitral valve prolapse, one or both leaflets of the valve are too large, or the chordae tendinea (the strings attached to the underside of the leaflets, connected to the ventricular wall) are too long (redundant), resulting in uneven closure of the valve during each heartbeat. Because of uneven closure of the leaflets, the valve bulges back, or "prolapses," into the left atrium like a parachute. When this happens, a very small amount of blood may leak through, moving backward from the ventricle to the atrium.

The valve still wo...

Read the Mitral Valve Prolapse article »



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