Brief Answer:
many different possible causes

Detailed Answer:
HI, thanks for using healthcare magic

There are a number of different possible causes for an increase in pulse rate.

In a normal heart beat , a ' signal' or 'stimulus' is sent out from a very specific point in the heart called the sinus node.

This 'signal' then travels along a specific pathway to stimulate the rest of the heart to beat/ contract.

Abnormal heart beats occur if there is: (1) increased stimulation at the sinus node
(2) an abnormal area of the heart sending out 'signals' to beat
(3)intrinsic heart disease


The above can occur due to the following:(1) anemia
(2) thyroid disease- increase in thyroid hormone levels can cause elevated pulse rate
(3)side effect of medications
(4)heart disease such as atherosclerosis (blockage of blood vessels with cholesterol plaques, this reduces blood supply and can cause changes in the function of the heart)
(5) heart failure

(6)overuse of alcohol and caffeine, smoking
(7)anxiety or stress
(8)heart failure
(9)lung disease can also be associated with an increase in heart rate- pneumonia, pulmonary embolism (blockage of blood vessel in the lung)

(10)general infections or infections involving the heart
(11) electrolyte disturbance eg low potassium levels
(12)history of previous heart attack causing changes in the heart
(13) exercise

To determine the cause, your doctor may consider an ECG. If the ECG is normal and you are still having symptoms then a holter can be done.

A holter is essentially a 24 hour ECG.

In addition, your doctor may also suggest blood tests to check for anemia, thyroid disease and electrolyte disturbance.

The result of these tests would determine if any other tests are needed.

I hope this helps, feel free to ask any other questions

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