What is Normal Heartbeat?

The normal resting adult heart beats regularly at an average rate of 60-100 times per minute. How fast the heart beats (heart rate) is governed by the speed of electrical signals originating from the pacemaker of the heart, the SA node? It is approximately between 0.12 to 0.16 second. The electrical signals from the SA node travel across the atria and cause these two upper heart chambers to contract, delivering blood into the lower heart chambers, the ventricles. These electrical signals then pass through the AV node to reach the ventricles. Electrical signals reaching the ventricles cause these chambers to contract, pumping blood to the rest of the body, generating the pulse. This regular flow of electricity from SA node to AV node causing a regular contraction of the heart muscle is known as a “sinus” beat. During rest, the speed of electrical signals originating from the SA node is slow, thus the heart beats slowly. During exercise or excitement, the speed of signals from the SA node increases, and heartbeat quickens.References: medicinenet

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About mdmedicine

Medical student. Interested in learning and promoting medical field.
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2 Responses to What is Normal Heartbeat?

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