Return to Index
(Atrioventricular [AV] Block—Adult)
- First-degree heart block—This is the mildest form of heart block. In this case, the electrical signals from the SA node move more slowly than normal to the AV node, but all signals reach the ventricles. There are usually no symptoms, and heartbeat and rhythm are normal. This type of heart block is often found in well-trained athletes.
Second-degree heart block—A second-degree heart block means that some of the electrical signals are not reaching the ventricles. This causes dropped beats. There are two types of second-degree heart block:
- Type I second-degree heart block, also called Mobitz Type I or Wenckebachs AV block—The electrical signals become increasingly delayed with each heartbeat, causing a beat to be missed.
- Type II second-degree heart block, also called Mobitz Type II—In this type of heart block, some of the electrical signals do not reach the ventricles. This is less common, but more serious.
- Third-degree, or complete, heart block—This is the most serious type of heart block. In this condition, no electrical signals are able to reach the ventricles. The ventricles compensate by contracting on their own, but at a much slower rate than is safe for the heart to maintain full function.
|Anatomy of the Heart|
|Copyright © Nucleus Medical Media, Inc.|
- History of heart disease
- Use of medications
- Chest pain
- Shortness of breath
- Obtain treatment for any condition that may cause heart problems or heart disease. This will help prevent heart block.
- If possible, avoid medications that can cause heart block.
- Maintain a healthy weight and lifestyle. Get regular exercise, eat a heart-healthy diet, and minimize stress.
- Avoid excessive consumption of alcohol and caffeine.
- If you smoke, talk to your doctor about how you can successfully quit.
- Reviewer: Michael J. Fucci, DO
- Review Date: 12/2015
- Update Date: 12/20/2014