How Is the Heartbeat Regulated?

The human heart’s rhythmic contractions are regulated by cells in the heart called pacemakers. These cells generate electrical signals that cause the heart to contract. Sometimes, these nerves fail to fire at the correct rate, which leads to health problems. In such cases, doctors can install a mechanical device that produces the electrical charges for the heart.

The rhythmic firing of the heart’s muscle cells can only occur because the cells slowly lose their charge. This contrasts with the muscle cells of smooth and skeletal muscles. Additionally, an important feature of the electrical system of the heart is that the electric signal propagates through the heart muscle at different rates. This allows the atria to fill completely before discharging their contents into the ventricles.

Scientists have recently discovered the gene that is responsible for irregular heart rates in many people. Damage to the SCN10A gene increases a person’s chances for developing cardiac disease. However, some mutations in this gene benefit a person’s heart rate and pumping efficiency.

An artificial pacemaker is an electrical device that delivers electrical impulses to the heart when the heart’s natural function is impaired. It sends the impulses via long wires that attach to the patient’s heart.