Atrial extrasystoles and vagus nerve

[thedy]

Hi,

I am wondering how vagus nerve influence heart beats.The problem is,that I do not understand why vagus nerve irritation makes atrial extrasystoles.Because as I know,vagus nerve inhibit heart rythm. So how is it?

What is the mechanism by which vagus or parasymphathetic causes extrasystoles or premature beats?If I irritate vagus I inhibit rythm,not even to make more beats.......Sympathetic irritation gives more logic to cause extrasystole,but parasympathetic???

 

Thanks for answers and sorry for my english.