Basic ECG Interpretation For Beginning Nursing Students
By [http://ezinearticles.com/?expert=Phil_Q_Rubis]Phil Q Rubis
If you are a budding nursing student and are looking for ways to understand the all important ECG simulators, either because you are preparing for your nursing exam, or because you just want a refresher so to brush up on reading the ECG printouts in the hospital setting, then you will want to go over this information.
Or, perhaps you are a nursing technician who is reading the ECG printouts in your daily job testing patient monitors with ECG simulators. You will find here a simple explanation of the basic ECG patterns which will constitute a baseline with which all the more complicated arrhytmic heart patterns will be compared.
In this article, we will explain the ECG, electrocardiogram, signal in the simplest possible terms. This should help you establish a baseline for your more comprehensive study.
First, consider the flow of blood through the heart sections
For the purpose of the explanation of the cardiogram, let's first establish the naming: Atrium is the upper part of the heart, Ventricle is the lower, bigger part of the heart. Between them, there is a heart valve which is designed to open in the direction of the blood flow. The blood always flows in the direction from the atrium to the ventricle. The valve design prevents the blood from flowing in the opposite direction.
The flow of electric impulses follows the flow of blood
The electric impulses that regulate the contractions of the heart have their own pathway from their origin in the "sinus" section of the top of the wall of the atrium. Starting in the atrium, the initial signal will cause the contraction of the atrium. From there, the electric signal lines go through the dividing region between the atrium and the ventricle (the AV region), where the signals get significantly delayed in time. Then, they move through the walls of ventricle where they finally cause the contraction of the ventricle.
The ECG signal mimics the flow of the electric impulse through the walls of the heart
The normal ECG signal is composed of the phases P, QRS, and T. The ECG signal in time follows the electric signal passing from the "sinus" section of the atrium, through the atrium, the AV section, and finally to the ventricle. So, the sequence of the repeating pulses you will see in the electrocardiogram printout will be as follows:
P phase which takes about 0.1s is a small pulse representing atrial depolarization which is associated with atrium contraction. After a delay, the next phase is
QRS complex phase take about 0.1s is a large pulse representing ventricular depolarization which is associated with ventricular contraction. The phases Q and S are actually slightly negative, while the phase R is strong and positive. Incidentally, as the valve closes, the atrial repolarization takes place which is associated with atrium expansion. This, however, is hidden due to the size of the ventricular depolarization signal. Finally, the last phase is
T phase which represents ventricular repolarization, corresponding to the slower expansion of the ventricle.
The entire process then normally repeats itself.
This is the basic normal heart beat ECG signal, in a nutshell. ECG interpretation made easy.
If you are studying ECG rhythms for any kind of exam, such as nursing school exam or ACLS exam, you will find more information on heart rhythm types on this site [http://ecgsimulator.org/ecg_interpretation.html]http://ECGSimulator.org/ecg_interpretation.html. In particular, check out the section about [http://ecgsimulator.org/acls_simulator.html]ACLS simulator.
Article Source: [http://EzineArticles.com/?Basic-ECG-Interpretation-For-Beginning-Nursing-Students&id=6185347] Basic ECG Interpretation For Beginning Nursing Students