Heart Block

What is heart block?

Heart block is also called an atrioventricular (a-tre-o-ven-TRIK-u-ler) or AV block. Heart block occurs when there is a delay or interruption in the flow of electrical signals in the heart. The flow of electrical signals controls the way the heart pumps out blood. Normally, the signals come from the atrium (upper chamber of the heart) then pass through to the ventricle (lower chamber of the heart). The electrical signals spread to the ventricles causing the muscles to pump blood.

With heart block, the electrical signals slow down or do not pass through to the ventricle. This may cause the ventricles to pump blood, but at a slower rate. At first you may not know that you have a heart block. Heart block is often a serious condition that needs immediate treatment.

What causes heart block?

Heart block is often caused by problems with the electrical paths of the heart. This may result from the swelling and scarring of heart tissues from previous heart conditions. This may include myocardial ischemia (decreased blood supply to the heart), infections, tumors, or surgery. Certain heart medicines may also cause heart block. Heart block may also be a condition that you are born with.

What are the signs and symptoms of heart block?

Heart block can be grouped into first-, second-, and third-degree heart blocks. The electrical signals that cause the heart to beat are either slowed, partially blocked, or completely blocked. Signs and symptoms depend on how severe the heart block is.

First-degree heart block often has no symptoms. Symptoms of dizziness, fainting, confusion, and tiredness may be seen in second- or third-degree heart block. You may also have low blood pressure and abnormal heartbeat in complete or third-degree heart block.

How is heart block diagnosed?

Caregivers often use the following tests to diagnose heart block:

• Ambulatory monitoring: This is also known as a Holter monitor, ambulatory electrocardiogram, or loop monitor. These devices record your heartbeat from several hours to days or weeks. Sticky pads are placed on your chest. The pads are connected with wires to a small device. The machine can be attached to your belt so it does not interfere with your everyday activities. Your caregivers look at the reading to see problems with your heartbeat.
  
  
• Echocardiogram: This test is a type of ultrasound. Sound waves are used to show the structure, movement, and blood vessels of your heart.
  
  
• Heart monitor: This test is also called an EKG or ECG. Sticky pads are placed on your skin to record your heart's electrical activity. An EKG gives information about how your heart is working. Lie as still as possible during the test.
  
  
• Exercise stress test: This test helps caregivers see the changes that take place in your heart during exercise. It checks for blockages in the arteries of your heart. An EKG is done while you ride an exercise bike or walk on a treadmill. Caregivers will ask you how you are feeling during the test. They want to know if you have chest pain or trouble breathing.

How is heart block treated?

Treatments depend on how severe your heart block is. Sometimes no treatment is needed especially when there are no symptoms. When symptoms are severe, the following treatments may be needed:

• Heart medicine: This medicine is given to strengthen or regulate your heartbeat. It also may help your heart in other ways. Talk with your caregiver to find out what your heart medicine is and why you are taking it.
  
  
• Implanted cardioverter defibrillator:
  
  
  • An implanted cardioverter defibrillator is also called an ICD. It is a small device that monitors your heart rate and rhythm. If your ICD senses that your heart is beating in an unhealthy rhythm, it will give your heart a small electrical shock. This helps your heart start beating normally again.
    
    
  • An ICD is made up of a generator and leads (thin, flexible wires that attach to your heart). The generator and the leads will be placed inside you during a procedure. The generator has a metal shell with a battery and a small computer inside.
  
  
• Temporary pacemaker:
  
  
  • This is a machine that helps your heart beat at a normal speed and in a regular rhythm. A temporary pacemaker may use large patches placed on your chest and back. These are connected to a special monitor. Sometimes, your caregiver may need to put small wires through your skin and into your heart muscle instead. The wires may then be connected to a small pacemaker box outside of your body.
    
    
  • The temporary pacemaker "reads" what your heart is doing. If your heart is beating in a different way than it should, the pacemaker takes over and controls your heartbeat. It does this by sending small electric signals to the heart muscle. This tells your heart when to beat. You may feel these signals, especially if your temporary pacemaker uses large patches on the skin. If this causes pain, use your call light and tell your caregiver. Do not get out of bed without first asking your caregiver if it is OK. You may need a pacemaker just for a short time. In some cases, you may need it for the rest of your life. If so, your caregiver may replace your temporary pacemaker with a permanent one.
  
  
• Permanent pacemaker:
  
  
  • A permanent pacemaker is a small device that helps control your heart rate. A permanent pacemaker is about the size of a wristwatch, and is implanted under your skin. You may need a pacemaker to slow your heartbeat down, speed it up, or make it more regular.
    
    
  • A pacemaker is made up of leads and a generator (battery). Getting a pacemaker involves having a procedure done. Most pacemakers work only when they are needed. These are called demand pacemakers. Other pacemakers work all the time. Your caregiver will decide which pacemaker is right for you.

Where can I find support and more information?

Having a heart block may be a life-changing disease for you and your family. Accepting that you have a heart block may be hard. You and those close to you may feel sad, worried, or frightened. These feelings are normal. Talk to your caregivers, family, or friends about your feelings. You may also want to join a support group with other people who have heart block. Call or write the following organizations for more information:

• American Heart Association
  7272 Greenville Avenue
  Dallas , TX 75231-4596
  Phone: 1- 800 - 242-8721
  Web Address: http://www.heart.org
  

• Heart Rhythm Society
  1400 K Street NW, Ste 500
  Washington , DC 20005
  Phone: 1- 202 - 464-3400
  Web Address: www.hrsonline.org
  

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment.

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