Questions tagged [electrocardiogram]
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30 questions
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Why in left bundle branch block the wave for the depolarization of the septum does not reach zero potential?
Considering V1 and right bundle branch block. Depolarization moves from the left septum to the right septum. When depolarization has passed half way through the septum, we get the maximum voltage of ...
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How can we have zero voltage on the ECG when the atria and ventricles are never the same charge at the same time?
Electrocardiography is based on the potential difference between two electrodes. The ST segment represents the period of time where the ventricles are completely depolarized, hence we get zero ...
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ECG: vector perpendicular to lead axis and its pattern
I have come across a contradiction while learning about ECG.
Some sources say that a biphasic deflection (two waves of same size but of opposite directions) is drawn on ECG tracing if the electrical ...
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Should we invert other ECG leads if aVR was positive?
I would like to seek your kind guidance in understanding the right way of solving this question. (for the context, so far we only covered normal ECG and axis deviation)
The question displays all 12 ...
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How to determine QRS voltage from ECG?
Attached below is a question from my textbook "Guyton and Hall Textbook of Medical Physiology Review, 4e" and I am confused because the solutions manual has the answer as B (0.5mV), implying ...
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How to determine the "argument" of the electrical axis of the ECG from aVF ＆ VI
This question is a continuation of the following question;
Is the definition of aVF consistent with Novosel’s formula?
Unfortunately, the article at the following URL is written in Japanese, but its ...
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Is the definition of aVF consistent with Novosel’s formula?
"In regards to the electrocardiogram, there is often a Statement made that,
'The a' in aVF means 'augmented' by a factor of 1.5 for sensitivity adjustment.
If the above statement is true, ...
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On an ECG, do we take the J point to be the baseline or the TP segment?
I'm studying current of injuries and the diastolic current theory is explained as such:
The ECG machine is programmed
to keep the T-P segment at baseline with everything else on the strip moved up or ...
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How is adding up action potentials equivalent to measuring the direction of depolarization vectors?
An ECG of the heart measured from lead II looks like this:
I have seen two ways of arriving at this image, the first is by considering the depolarization and the repolarization vectors and their ...
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Difference between strength and hypertrophy?
Doctors tell us to do lots of cardio exercise to "strengthen" the heart. Then some people get hypertrophy (another form of heart muscle growth) and it's considered "abnormal" (even ...
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ECG-Lead 1 vs Lead 2
I am new to this and I am trying to do some filtering on ECG signals.
I am working on Lead I signals but they appear too noisy. However, Lead II singals appear significantly less noisy whilst having ...
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Is this a P-wave on single-lead ECG
I am an engineer working on a project using ECGs. I am trying a few techniques and I was wondering whether the P-wave is still visible in the ECG after filtering it. The issue is that I believe the ...
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Augmented lead equations
Extremely confused with augmented lead equations. Apparently -
aVL = (Lead I - Lead III) ÷2
-aVR = (Lead I + Lead II) ÷2
aVF = (Lead II + Lead III) ÷2
I can't figure out why we're subtracting Lead III ...
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Reason for ecg volume conduction waveform?
Can somebody for the love of humanity and genuine curiosity explain why does the voltage between 2 oppositely charged ends of a progressively depolarizing cell peak when the wave reaches the middle ...
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EKG reading question [closed]
Can someone tell me what "ETRSR1-RSR' in V1 or V2, right VCD or RVH-QRS area positive & R' V1/V2 " means? In other comments it also said "otherwise normal EKG"
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