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.
A slow heart rate is common during a heart attack. Bradycardia is a heart rate below 60 beats per minute and often with a heart attack is associated with chest pain or angina. If the heart rate is too slow, often below 40 beats per minute, dizzyness, passing out, inability to concentrate and dangerously low blood pressure result.