Chinese medicine believes that long-term fatigue will cause deficiency of both heart and kidney, so it is recommended that your mother take more rest. Take good care of him and let him eat some food that can invigorate qi and nourish heart. It is normal for a person's heart to be 60- 100 a minute, so don't worry too much. But I suggest your mother go to the hospital for a routine check-up.
I hope everyone's mother is healthy.