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Real-Time Cardiac Mapping with a Noninvasive Imageless Electrocardiographic Imaging System
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Three pauses and three P waves: what is the mechanism?
Matthew Wright1, Sébastien Knecht, Seiichiro Matsuo
1Hôpital Cardiologique du Haut-Lévêque and the Université Victor Segalen Bordeaux II, Bordeaux, France. mattwright007@btinternet.com
Journal of Cardiovascular Electrophysiology
|February 13, 2008
Abstract
No abstract available in PubMed .
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The electrical signals recorded on an electrocardiogram (ECG) occur before the mechanical processes of contraction and relaxation during the cardiac cycle.
A cardiac action potential originates in the SA node and spreads throughout the atria and the AV node in approximately 0.03 seconds. This results in the P wave in an ECG and triggers atrial contraction. The action potential is then briefly slowed at the AV node, allowing the atria to contract and fill the ventricles with blood before...
A cardiac action potential originates in the SA node and spreads throughout the atria and the AV node in approximately 0.03 seconds. This results in the P wave in an ECG and triggers atrial contraction. The action potential is then briefly slowed at the AV node, allowing the atria to contract and fill the ventricles with blood before...
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The cardiac action potential process involves a series of phases characterized by the movement of ions across the cardiac cell membranes, leading to the depolarization and repolarization of the cardiac myocytes.
Ionic Basis of Cardiac Action Potentials
01:13The Cardiac Cycle
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The Process
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