What is the meaning of P-R shortening?

Patient's question:

Currently, under general circumstances: Occasionally heart tired
Auxiliary examination: Physical examination has this problem

Doctor's answer:

The P-R interval is the time from the atria to the ventricles. A slight shortening is of little clinical significance, while a more significant shortening is common in preexcitation syndrome, where the bypass pathway is faster. It is recommended to pay attention to rest, stay warm, drink more hot water, maintain a balanced diet, have a regular schedule, relax and regulate emotions, avoid overexertion, eat more fruits and vegetables, avoid spicy and cold foods, exercise moderately, boost immunity, stay away from noisy environments, quit smoking and limit alcohol consumption, and maintain a positive mindset.