You must be at least 17 years old to donate to the general blood supply, or 16 years old with parental/guardian consent, if allowed by state law. Learn more about the reasons for a lower age limit.
Other Causes of Elevated Heart Rate. Elevated heart rate when sick is actually your heartâs aid in order to quell the sickness. However, there can be other causes for elevated heart rate as well. Electrical signals produced and sent to the heart tissues are responsible for controlling the heart rate.
Not a Normal Heart Rhythm or Rate. Usually the atria and ventricles work together so the heart pumps blood in steady rhythm. But in AFib, they don't. The irregular beats can cause a fast, fluttering heart rate -- 100-175 beats per minute -- instead of the normal 60-100 beats per minute.