Step I conduction velocity heart

[Yoyomama88]

conduction velocity in the heart: Why do the purkinjes have the fastest conduction, but AV the slowest?

Can anyone explain this physiologically?

 

[AndyRSC]

The AV node/bundle conduction is slow due to diminished gap junctions between cells, taking ~ 0.09 sec and 0.04 sec, respectively; there is an abundance of gap junctions in intercalated discs between Purkinje fiber cells, therefore traversing entire expanse of ventricle only takes 0.03 sec after depolarization front exits the septum.

 

[FIREitUP]

The AV node/bundle conduction is slow due to diminished gap junctions between cells, taking ~ 0.09 sec and 0.04 sec, respectively; there is an abundance of gap junctions in intercalated discs between Purkinje fiber cells, therefore traversing entire expanse of ventricle only takes 0.03 sec after depolarization front exits the septum.

Good answer. The only thing I would add is the increase in fiber diameter also increases conduction velocity in the purkinje fibers.

 

[OveractiveBrain]

conduction velocity in the heart: Why do the purkinjes have the fastest conduction, but AV the slowest?

Can anyone explain this physiologically?

Jesus said so, and it was.

Even before Jesus existed it was this way. Thus is the power of Jesus.

I may be wrong, though, cause Jesus is the janitor. Smart guy though.

 

[herewego]

You want to slow conduction in AV node to make sure the ventricles are ready, but once you get the conduction to the ventricles (purkinje), you want conduction to be fast and uniform.