Heart Block, Congenital

Synonyms

• Atrioventricular (AV) Block

Disorder Subdivisions

• First Degree Congenital Heart Block
• Second Degree Con. Heart Block (Wenckebach [Mobitz I]; Mobitz II; included)
• Third Degree Congenital (Complete) Heart Block

General Discussion

Congenital heart block is characterized by interference with the transfer of the electrical nerve impulses (conduction) that regulate the normal, rhythmic, pumping action of the heart muscle (heart block). The severity of such conduction abnormalities varies among affected individuals.

The normal heart has four chambers. The two upper chambers are the atria and the two lower chambers are the ventricles. Within the right atrium of a normal heart is a natural pacemaker that initiates and controls the heartbeat. The electrical stimulus travels from the pacemaker (sinoatrial or SA node) to the ventricles along a very specific path consisting of conducting tissue and known as the AV (atrioventricular) node. As long as the electrical impulse is transmitted normally, the heart behaves normally.

If the transmission of the signal is impeded, the blocked transmission is known as a heart block or an AV block. If the heart block occurs in the fetus or newborn, the condition is known as congenital heart block. This condition has nothing at all to do with the flow of blood or with the blockage of a major or minor coronary artery. It is an electrical problem rather than a hydraulic one.

Heart blocks are categorized according to the degree of impairment of the patient. The categories are first, second and third degree heart block

Resources

American Heart Association
National Center
7272 Greenville Avenue
Dallas, TX 75231-4596
Tel: (214)373-6300
Fax: (214)373-0268
Tel: (800)242-8721
Email: inquire@heart.org
Internet: http://www.americanheart.org

Congenital Heart Anomalies, Support, Education, & Resources
2112 North Wilkins Road
Swanton, OH 43558
Tel: (419)825-5575
Fax: (419)825-2880
Email: chaser@compuserve.com
Internet: http://www.csun.edu/~hcmth011/chaser/chaser-news.html

International Bundle Branch Block Association
6631 West 83rd Street
Los Angeles, CA 90045-2875
Tel: (310)670-9132

NIH/National Heart, Lung and Blood Institute
31 Center Drive MSC 2480
Building 31A Rm 4A16
Bethesda, MD 20892-2480
Tel: (301)592-8573
Fax: (240)629-3246
Email: nhlbiinfo@rover.nhlbi.nih.gov
Internet: http://www.nhlbi.nih.gov/

Kids With Heart National Association for Children's Heart Disorders, Inc.
1578 Careful Dr
Green Bay, WI 54304-2941
Tel: (920)498-0058
Fax: (920)498-0058
Tel: (800)538-5390
Email: kidswithheart@greenbaynet.com
Internet: http://www.kidswithheart.org

Little Hearts, Inc.
P.O. Box 171
Cromwell, CT 06416
USA
Tel: 8606350006
Fax: 8606350006
Tel: 8664354673
Email: info@littlehearts.org
Internet: http://www.littlehearts.org

Congenital Heart Information Network
1561 Clark Dr
Yardley, PA 19067
Tel: (215)493-3068
Fax: (215)493-3068
Email: mb@tchin.org
Internet: http://www.tchin.org

For a Complete Report

This is an abstract of a report from the National Organization for Rare Disorders, Inc. ® (NORD). A copy of the complete report can be obtained for a small fee by visiting the NORD website. The complete report contains additional information including symptoms, causes, affected population, related disorders, standard and investigational treatments (if available), and references from medical literature. For a full-text version of this topic, see http://www.rarediseases.org/search/rdblist.html

The information provided in this report is not intended for diagnostic purposes. It is provided for informational purposes only. NORD recommends that affected individuals seek the advice or counsel of their own personal physicians.

It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report.

This disease entry is based upon medical information available through the date at the end of the topic. Since NORD's resources are limited, it is not possible to keep every entry in the Rare Disease Database completely current and accurate. Please check with the agencies listed in the Resources section for the most current information about this disorder.

For additional information and assistance about rare disorders, please contact the National Organization for Rare Disorders at P.O. Box 1968, Danbury, CT 06813-1968; phone (203) 744-0100; web site www.rarediseases.org or email orphan@rarediseases.org

Last Updated: 5/12/2006
Copyright 1988, 1989, 1997, 1998, 2006 National Organization for Rare Disorders, Inc.