Hey, here's something that crossed my mind:
Why is it, that in some instances, breathing in may cause an ectopic beat? Is it something to do with increases blood return going into your heart breathing in, or what? I was curious about this too, but forgot to ask about it.
Regards to everyone.
You are right. By the way, breathing is more likely to cause PACs than PVCs.
When breathing in, venous return to the heart (preload) is increased. This is "stretching" the atria, making ectopic beats more likely to occur.
In some people (mostly at age below 40), the heart speeds up when inhaling, decreasing this effect (as the heart pumps more frequent rather than heavier beats) and if so, this effect is lower. But it is a normal phenomenon.