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It is on page 374 of your lab book assuming this is the same question that came out Lab 28 in the Ninth Edition of Seeley's Anatomy & Physiology. The atrial repolarization occurs during ventricualr depolarization and is masked by the larger QRS complex. I actually did my homework :)
[non-professional opinion]
Atrial repolarization is a much lower voltage event than atrial depolarization (the P wave) and it usually occurs during ventricular depolarization (the QRS complex).
Therefore, it is too small to be clearly distinguished from noise on most EKGs and even if it were strong relative to the noise, would typically be obscured by the much stronger QRS complex.
You can't see atrial repolarization on surface ECGs because it's too small a current to get out of the body at the voltages present in the heart.
Atrial repolarization is also timed so that the QRS complex would stomp on it, even if you could see it on a surface lead, and that's often the answer given to this question by non-cardiologist physicians and allied health professionals of every stripe; unless the prof of the course you're using answers.com to, uh, "assist" you with is an actual cardiologist, he or she might be looking for that one. (It would be best to look in the assigned source material. . .)
because it happens during myocardial depolarization (QRS-complex)
Because the atria repolarize while he ventricles are contracting, so the signal is completely hidden.
Atrial repolarization is not seen because the atrium repolarizes while the ventricle is depolarizing and is incorporated into the QRS complex.
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What is atrial repolarization indicated by?
The atrial repolarization occurs during the QRS complex of the ECG but is obscured by the ventricle depolarization.
Atrial repolarization coincides in time with?
the ventricular depolarization, which masks the atrial repolarization wave on the electrocardiogram. This is because the QRS complex is much larger than the atrial repolarization wave and overlaps with it, making it difficult to distinguish on the ECG.
Why is the ECG event indicating atrial repolarization not seen in an ECG?
The atrial repolarization event is usually hidden by the larger QRS complex in the ECG, making it difficult to distinguish. The electrical activity from the atrial repolarization is masked by the ventricular depolarization signals.
What is the portion of the ECG that indicates ventricular repolarization?
The wave indicating atrial repolarization wave is hidden by the QRS complex. Ventricular repolarization is indicated by the T wave.
What are the three types of deflection waves seen in a typical ECG?
The three types of deflection waves seen in a typical ECG are the P wave (atrial depolarization), the QRS complex (ventricular depolarization), and the T wave (ventricular repolarization). They represent the different electrical activities of the heart during each phase of the cardiac cycle.
What is the correct order of ECG waves?
P wave - represents atrial depolarization (contraction) QRS complex - ventricular depolarization T wave - ventricular repolarization (relaxation) atrial repolarization is "buried" within the QRS Complex
The deflection waves in an ecg tracing include?
The deflection waves in an ECG tracing include the P wave (atrial depolarization), QRS complex (ventricular depolarization), and T wave (ventricular repolarization). Each of these waves represents different electrical activity of the heart during a cardiac cycle.
What portion of the ECG indicates ventricular repolarization?
The portion of the ECG that indicates ventricular repolarization or recovery is the t wave. It is the wave found after the QRS complex (Ventricular depolarizaton) in a normal ECG
The portion of the ECG that corresponds to atrial depolarization is the?
P wave corresponds to atrial depolarization in an ECG.
Why is PQRST used in the ECG waves?
PQRST represents the five key components of a normal cardiac cycle on an ECG trace: P wave (atrial depolarization), QRS complex (ventricular depolarization), T wave (ventricular repolarization), and sometimes the U wave (late ventricular repolarization). Analyzing these waves helps to identify abnormalities in the heart's electrical activity.
Which part is atrial systole in ECG?
identify the portion of the ECG that represents the electrcal activity associated with atrial systole.
The T wave of an ECG pattern represents the repolarization of the?
Ventrical MuscleFibers
