HEART BLOCK

General Information

DEFINITION--A persistent disruption (either mild or major) in transmission of electrical signals between the heart's upper and lower chambers. Contractions of the atria (upper heart chambers) lose synchronization with those of the ventricles (lower heart chambers). The heartbeat is no longer regulated normally to quicken under exertion or stress and slow down at other times.

BODY PARTS INVOLVED--Heart's electrical-transmission system that coordinates contractions of heart-muscle cells. The heart's natural pacemaker initiates the electrical system.

SEX OR AGE MOST AFFECTED--All ages, but most common in men over 40 and women after menopause.

SIGNS & SYMPTOMS

• No symptoms (sometimes) for less-severe forms.
• Slow, irregular heartbeat.
• Sudden loss of consciousness.
• Convulsions (sometimes).
• Attacks of dizziness, weakness or confusion.

CAUSES

• Coronary-artery disease, a sign of atherosclerosis (hardening of the arteries).
• Congenital heart abnormalities.
• Excessive digitalis and some other medications.
• Some heart blocks are seen in well-trained athletes.

RISK INCREASES WITH

• Adults over 60.
• Stress.
• Improper diet that is high in fat and salt.
• Obesity.
• Smoking.
• Diabetes mellitus.
• Heart disease, including atherosclerosis, congestive heart failure or heart-valve disease.
• High blood pressure.
• Previous electrolyte imbalance.
• Use of some drugs, such as digitalis, quinidine or beta-adrenergic blockers.

HOW TO PREVENT

• Obtain medical treatment for any underlying disease.
• Don't smoke.
• Exercise regularly.
• Eat a diet that is low in fat and low in salt (see Appendix for both).

What To Expect

DIAGNOSTIC MEASURES--

• Your own observation of symptoms.
• Medical history and physical exam by a doctor.
• ECG (See Glossary). The ECG provides information about the degree of heart block (1st, 2nd or 3rd) and will help determine what treatment, if any, is appropriate.

APPROPRIATE HEALTH CARE

• Self-care after diagnosis. Some heart blocks require no treatment.
• Doctor's treatment.
• Surgery to implant an artificial pacemaker (sometimes). It provides a regular, mild electric stimulus that maintains a normal heartbeat.

POSSIBLE COMPLICATIONS--Uncontrolled slow, rapid or irregular heartbeat and cardiac arrest.

PROBABLE OUTCOME--

• Heart blocks that do not bring on symptoms usually require no treatment.
• More serious heart blocks can be controlled with surgery to implant a pacemaker.

How To Treat

GENERAL MEASURES--

• Wear a Medic-Alert bracelet or pendant (See Glossary) in case you suddenly lose consciousness.
• Don't smoke.
• See Resources for Additional Information.

MEDICATION--

• Your doctor may prescribe atropine for short-term therapy.
• Don't take medications to relieve allergy or nasal congestion. They can worsen symptoms.

ACTIVITY--Don't think of yourself as an invalid. Unless your doctor advises against it, mild exercise is helpful and not to be feared. Begin a regular exercise program--walking is ideal.

DIET--

• Lose weight if you are overweight (see Weight-Loss Diet in Appendix).
• Avoid excessive use of alcoholic beverages. Alcohol depresses the heartbeat.

Call Your Doctor If

• You have symptoms of heart block, especially an episode with loss of consciousness.
• After diagnosis, stress increases in your life.