Anatomy & Physiology Online - Cardiac conduction system and its relationship with ECG

[luvztc5]

so PR segment just show signal spread to AV node ..??? or to ventricles ...??? so then, what does the PR interval show??

[primalpicturesltd]

@luvztc5

The PR segment and the PR interval have similar names, but represent different things on the ECG (try pausing the video at 38 seconds to see the difference).

The PR segment is the flat part of an ECG between the end of the P wave and the start of the QRS complex. During the PR segment, the electrical signal passes from the AV node and into the ventricles, before the ventricles start to contract.

However, the PR interval is the P wave AND the PR segment together.

Hope that helps.

[milanello2007]

great vedio :) like it

it makes the understanding of normal ECG is simple & useful

:)

[galenblake821]

This is one very "subdued" video. =p

[sheilayoyo]

thxxx thxxxxxxxx u so much this really helpeddd :)

[kinseb10]

How can ventricles myocard relax before it is repolarised! I am sorry



[Multibjarne]

This is so great

[DaLoneFreeMarshmallo]

Great, thanks! :)

[BLISSx86]

Thank you!

[brownricegirl]

exactly the diagram and schematics that I need! Thanks!

[UsersUnavailable]

Excellent Video! Very clearly explained, straight forward, and easy to understand, although I did have to watch it multiple time to really grasp the entire concept.

Thanks a lot!!!

[MPDargo]

Great video! Took me 3.35 min to learn the wiggers. Gotta love youtube.

[NINEKILLER]

very usefull

[Amanda9993]

excellent video

[Amanda9993]

excellent video

[gototow]

thanx 

[tabblets]

why couldn't all things be this easy. AH-MAZING!

[takeontherocks]

excellent///

thanks



[shanittrainer]

you are excellent your demo equals 100s of pages of texts. Wow...

[Technognosia]

you rock ! thnx !



[zahrasuhardi]

what does the ST segment show again? is the the ventricular contraction???

[SoCuteNY]

@zahrasuhardi My pathophys teacher described it as the "EKG silence" ventricules are depolarized, but have not yet been repolarized. Its usually elevated during a MI (ST-Elevation Myocardial Infarction) or Depressed during ischemia (Unstable Angina or a NON-ST elevation MI)

Hope that helps!

[zahrasuhardi]

@SoCuteNY oh i see, thanks so much!!!

[primalpicturesltd]

@zahrasuhardi Yes, the ventricles do contract during this phase.

Contraction of the ventricular contractile fibers occurs during the S-T segment, between the end of the S wave and beginning of the T wave.

The ST segment, also referred to as the isoelectric period, represents the period in which the entirety of both ventricles is depolarized. This roughly corresponds to the plateau phase of a ventricular action potential.

Hope this answers the question.

[Myrealm7]

i love you

[DrBrainyBrain]

I'm grateful! Excellent job!!!! It became more clear!

[noory106]

good job

[scott441974]

Great Job, Very Helpful!!

[wtfiku]

very helpful and clear with animation and labels. thanks

[adae52]

there is mistake in st segement you don't mention (plateau

[primalpicturesltd]

@adae52 The information presented in this animation is correct.

It is true that the voiceover itself does not mention that the S-T segment corresponds to the plateau phase of a ventricular action potential, but this information is present in the text that accompanies the animation . The information provided give an accurate account of an echocardiogram (ECG/EKG), and any additional information required for a 2 semester A & P course.