atrial fibrillation

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atrial fibrillation

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8 Posts

doc4life
Forum Guru

Topics: 131
Posts: 240

09/24/03 - 01:06 AM

In Atrial Fibrillation.the ventricular rate depends on--------

A. cONDUCTION VELOCITY THROUGH ATRIAL SPECIALIZED TISSUE

B. conduction velocity from ventricular endocardium to epicardium

C. discharge rate of purkinje fibers

D. discharge rate of SA node

E. refractory period of AV junction

mariam
Forum Newbie

Topics: 7
Posts: 35

09/24/03 - 08:20 PM

is it E ??

doc4life
Forum Guru

Topics: 131
Posts: 240

09/24/03 - 11:00 PM

Yes u r absolutely correct

drrabines
Forum Elite

Topics: 90
Posts: 184

01/08/04 - 04:24 PM

But if yuo are in Fibrilation how can would be a refractory period, I think it is C, because to depolarize ventricules you must depolarize purkinge, so it depends of what aberrant atrial focus raise the AV node first

mjl1717
Forum Hero
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Topics: 958
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01/08/04 - 04:43 PM

My friend -I believe doc4life already passed Step1

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Smell the coffee! "Is That an Osler move??"

01/08/04 - 05:06 PM

You cannot pass with one question, and maybe i am wrong so i answer if you be so kind to give and explanation
Doc ( CONGRATULATIONS )

meg
Forum Guru

Topics: 62
Posts: 806

01/09/04 - 07:08 AM

it is the refractory period that determines the ventricular rate in Atrial fib. That is why in atrial fib, you give Digoxin to slow the conduction through AVnode and lower the ventricular rate.

leftfoot
Forum Elite

Topics: 29
Posts: 216

01/29/04 - 01:58 PM

i agree with choice E also.
the wave of depolarisation takes the longest to pass through the AV node and thats what decides at what rate the ventricle depolarises!

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