• Impaired conduction of cardiac impulse occurring anywhere along the conduction pathway.
  Human Phenotype Ontology (HPO)
  The Human Phenotype Ontology Project, 2021
• Impaired conduction of cardiac impulse that can occur anywhere along the conduction pathway, such as between the SINOATRIAL NODE and the right atrium (SA block) or between atria and ventricles (AV block). Heart blocks can be classified by the duration, frequency, or completeness of conduction block. Reversibility depends on the degree of structural or functional defects.
  NLM Medical Subject Headings
  U.S. National Library of Medicine, 2021
• Impairment of conduction in heart excitation; often applied specifically to atrioventricular heart block.
  CRISP Thesaurus
  National Institutes of Health, 2006
• The difficulty or inability of the electrical signal that triggers a heart contraction to pass through the atrioventricular node.
  Harvard Dictionary of Health Terms
  Harvard Medical Publishing, 2011
• Heart block is a delay in the conduction of electrical current as it passes through the conduction system of the heart, including the atrioventricular node, bundle of His, or both bundle branches, all of which are located between the atria and the ventricles.
  Merck Manuals
  Merck & Co., Inc., 2020
• Heart block, lack of synchronization in the contractions of the upper and the lower chambers of the heart--the atria and the ventricles. The lack of synchronization may range from a slight delay in the ventricular contractions to total heart block, a complete lack of synchronization between the...
  Encyclopedia Britannica
  Encyclopedia Britannica, Inc., 2020