1. Heart block -- MedicineNet
Heart block definition - Medical Dictionary definitions of popular medical terms. medical dictionary A-Z List > Heart block. Online Medical Dictionary and glossary with medical definitions. online medical dictionary A-Z List.
http://www.medterms.com/script/main/art.asp?articlekey=3670

2. Heart Block, Congenital - General Discussion -- Information from Healthwise
It is possible that the main title of the report Heart Block, Congenital is not the name you expected. In complete heart block (Third Degree), the atria and ventricles beat independently. However, infants with complete heart block may experience...
http://www.everettclinic.com/kbase/nord/nord530.htm#nord530-general-discussion

3. Heart block -- Information from Health A to Z
Third-degree block, also called complete heart block, is the most serious. Heart block refers to a delay in the normal flow of electrical impulses that cause the heart to beat. Third-degree heart block is a serious condition that affects the...
http://www.healthatoz.com/healthatoz/Atoz/ency/heart_block.jsp