COMPLETE HEART BLOCK

COMPLETE HEART BLOCK

The heart is a muscular pump with four chambers, two upper (left and right atria) and two lower (left and right ventricles). These contract and pump blood. Special tissue in the heart
produces and sends electrical impulses to get the muscle to contract. Normal electrical signals start from the sinoatrial (SA) node in the wall of the right atrium. From there the signal goes
to the left atrium and reaches the atrioventricular (AV) node between the atria and ventricles. The signal then goes to the left and right bundle branches and fi nally the ventricles. There it
stimulates ventricles to contract. Heart block refers to a disturbance of these impulses. Thirddegree heart block, or complete heart block, is one of three types (fi rst- and second-degree blocks are the others). In complete heart block, no impulses from the atria reach the ventricles. Signals are completely blocked at the AV node.

cause
The exact cause is often unknown. Complete heart block isn’t contagious or passed from generation to generation. It usually occurs in elderly people and may be the result of aging. Heart conditions including coronary artery disease, myocardial infarctions (heart attacks), heart valve disease, and congestive heart failure can cause complete heart block. Other causes are diseases, such as sarcoidosis, rheumatoid arthritis, or Lyme disease, and some medicines (e.g., digoxin, beta-blockers, and calcium channel blockers).

symptom
Symptoms can vary and include dizziness, lightheadedness,
shortness of breath, chest pain, and fainting. Many people may
have no symptoms.

diagnosis
The doctor makes a diagnosis from the medical history and a very slow pulse at a physical examination. The doctor will order electrocardiography (ECG) to measure the heart’s electrical activity. If additional tests are needed to confi rm the diagnosis, a 24-hour recording of the heartbeat (Holter monitor) while following usual daily activities will be done. Sometimes, admission to a hospital is needed for constant monitoring in preparation for treatment.

treatment

No drugs can treat complete heart block. If excessive doses of a drug is the cause, stopping the drug is required. The best treatment for complete heart block not caused by drugs is insertion
of a pacemaker. Pacemakers are small, electrical devices put into the heart to tell it to beat to stimulate the heart to beat in a normal fashion.

Things to do

Do carry your pacemaker ID card. The card describes
the type of pacemaker, insertion date, model, and serial
number.

Do call your doctor if you pass out with no warning, feel
faint, or have chest pain or shortness of breath.

don't do

DON’T forget that certain devices such as cell phones
and powerful magnets can make the pacemaker malfunction

DON’T forget to tell doctors who suggest procedures
such as magnetic resonance imaging (MRI) that you have
a pacemaker.