If the vagus nerve would be cut, this would result in the heart rate speeding up. There will be an increase of about 25 beats per minute. Why is the vagus nerve so important? It is obviously something that can control people’s heartbeat.
This nerve is in charge of slowing down the heartbeat. Without it, the heart will not be able to slow down and this can be a dangerous thing. A heart that beats too fast may become overworked and it will burn out. People who have a faster heart rate as compared to other people are not recommended to make movements that will make their hearts beat even faster.
If the vagus nerve to the heart were to be cut, it would result in the heart rate speeding up by about 25 beats per minute.
It is called the vagus nerve, not the vagal nerve - although that is the name for stimulation of this nerve. This nerve is actually what helps the heart rate slow down, so cutting it means that the heart can’t slow down as much as it needs or wants to. This can be a dangerous thing.
If a heart beats too fast, it will burn out. There’s a reason that people with higher resting heart rates often find themselves having cardiac arrest - their heart didn’t get the break it needed by lowering that resting heart rate through exercising.