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Causes of Bradycardia in Heart

The term ‘Bradycardia’ means a slow heart rate, usually defined in an adult person as fewer than 60 beats per minute. It can be a serious problem if the heart doesn’t pump enough oxygen-rich blood to the body. It occurs when electrical signals slow down or are blocked.

General causes of Bradycardia-

In Athletes: The athlete’s heart is considerably stronger than that of a normal person and allows a large stroke volume output during rest. These excessive quantities of blood initiate feedback circulatory reflexes or other effects to cause Bradycardia when the athlete is at rest.

Vagal stimulation: In carotid sinus syndrome, an atherosclerotic process causes excess sensitivity of the baroreceptors in the arterial wall. As a result, increased external pressure on the neck causes the atherosclerotic plaque in the carotid sinus to stimulate the baroreceptors, which then stimule the vagus nerve and cause bradycardia.

Sinus node problems: Bradycardia often starts in the sinus node. A slow heart rate might occur because of the sinus node:

  • Discharges electrical impulses slower than is normal
  • Pauses or fails to discharge at a regular rate
  • Discharges an electrical impulse that’s blocked before causing the atria to contract

In some people, the sinus node problems result in alternating slow and fast heart rates (bradycardia-tachycardia syndrome).

Other things that can lead to it:

Certain medications, such as those to treat high blood pressure or irregular heartbeats

  • A congenital defect, or problem you’re born with
  • Thyroid disease, an imbalance of hormones in the body.