Bradycardia

Bradycardia is a term for a heart rate (pulse) that, in adults, is slower than 60 beats per minute. A normal rate is 60 to 100 beats per minute. A heart rate below 60 beats per minute may be normal for some adults with healthy hearts. If the rate is too slow, the heart may have trouble pumping the volume of blood the body needs. If the heart rate gets too low, blood flow to the brain may be decreased and may make you feel lightheaded, dizzy, or faint.

The heart has a natural pacemaker in the top of the heart called the SA node (sinoatrial or sinus node). This pacemaker sends out regular electrical signals to the muscle of the heart, telling the heart muscle when to beat (contract). The electrical signal travels from the upper parts of the heart (atria) through the AV node (atrioventricular node), to the lower chambers of the heart (ventricles). The ventricles squeeze, pumping the blood from your heart to your lungs and to the rest of your body.

CAUSES

  • Problem with the heart's electrical system.

  • Problem with the heart's natural pacemaker.

  • Heart disease, damage, or infection.

  • Medications.

  • Problems with minerals and salts (electrolytes).

SYMPTOMS

  • Fainting (syncope).

  • Fatigue and weakness.

  • Shortness of breath (dyspnea).

  • Chest pain (angina).

  • Drowsiness.

  • Confusion.

DIAGNOSIS

  • An electrocardiogram (ECG) can help your caregiver determine the type of slow heart rate you have.

  • If the cause is not seen on an ECG, you may need to wear a heart monitor that records your heart rhythm for several hours or days.

  • Blood tests.

TREATMENT

  • Electrolyte supplements.

  • Medications.

  • Withholding medication which is causing a slow heart rate.

  • Pacemaker placement.

SEEK IMMEDIATE MEDICAL CARE IF:

  • You feel lightheaded or faint.

  • You develop an irregular heart rate.

  • You feel chest pain or have trouble breathing.

MAKE SURE YOU:

  • Understand these instructions.

  • Will watch your condition.

  • Will get help right away if you are not doing well or get worse.