How would you react if you knew that your heart beats are a countdown to death?
Basically, the number of heart beats in the life span of each animal is almost determined. The upper limit is estimated to be about 1.5 billion times per life in most animals. Mice have an average heart rate of 600 beats per
minute and a life span of 5 years or shorter, whereas elephant's heart rate is 20-30 beats per minutes at rest and their life spans are as long as 50-80 years.
The same rule is also applied to human beings, although the total count of heart beats can double probably because of clinical medicine and public health. There is statistical evidence showing that those who have a lower heart rate can live longer than those who have a higher heart rate.
The point is that a life span might be expected on the basis of heart rates, to some extent.
Of course, aside from a heart rate, there are many determinants of life span, such as comorbidities, geographic location, gender, socioeconomic status. However, if you have a higher heart rate at rest, e.g., 100 beats per minute or more, you might as well go and see a physician. Something unfavorable may be hidden regardless of whether you are symptomatic or not.
Do not worry too much if your kids have a higher heart rate. Children's hearts are always beating with a lot of energy.