Dr. M.J. Bazos, MD Patient Handout


About Your Diagnosis
Bradycardia is a heart rate that is less than 60 beats per minute. Normal resting heart rates are 60 to 100 beats per minute with an adult average of about 75 beats per minute. Slow heart rates are not necessarily a sign of problems. Among well-conditioned persons such as long-distance runners, it is common to have a slow resting heart rate. For others, such as elderly persons, bradycardia may indicate problems with the sinus node, the site of impulse generation that signals the heart to beat. Medical causes of bradycardia include myxedema (low thyroid hormone), hypothermia (low body temperature), and head injuries. Many drugs can cause bradycardia, including some tranquilizers and blood pressure medications such as beta-blockers.

Living With Your Diagnosis
Bradycardia usually corrects itself when the person begins to exercise. This includes standing up to move around. If the heart rate does not increase with exertion, there may be a feeling of light headedness or faintness. Bradycardia may cause low cardiac output of blood, which can cause low blood pressure= and low delivery of blood to the brain or heart. This can cause fainting, fatigue, or chest pain. Persons with symptoms usually have normal examinations, and the slow heart rate is found only on an electrocardiogram (ECG). If someone is found to have bradycardia and symptoms of low cardiac output, medications that cause the condition have to be discontinued. All medical conditions that= cause bradycardia, such as myxedema, must be managed. Dehydration can worsen the symptoms of low blood pressure.

If no cause is found for the bradycardia and the patient continues to have symptoms, a pacemaker may have to be implanted to help the heart beat faster. A pacemaker is an electrical device with a wire to the heart muscle that signals the ventricles to contract regularly (fixed-rate pacers) or to contract faster in response to increased activity (demand pacers). Pacemakers may be external with the wire entering through a vein, or they can be implanted into the patient with a minor operation. Older pacemakers were susceptible to damage from microwaves and strong electronic equipment. New pacemakers are much safer and more reliable. Caution remains against strong magnetic or ultrasonic forces such as those used in some physical therapy settings or in airport security screens. Patients with pacemakers are given instructions by the cardiologist regarding maintenance and care of the pacemaker.

The DOs
•Make sure you have your condition thoroughly evaluated.
•Follow your doctor’s advice.

The DON’Ts
•Do not worry. If you have bradycardia and a normal exercise response without symptoms of low cardiac output, no treatment is required.

When to Call Your Doctor
•If you have worsening dizziness, fainting, chest pain, or shortness of breath.