Overview of Heart Block
(See also Overview of Abnormal Heart Rhythms.)
Heart block is a delay in the conduction of electrical current as it passes through the atrioventricular node, bundle of His, or both bundle branches, all of which are located between the atria and the ventricles.
Heart blocks can be divided into
Usually, no treatment is needed for either type when the block is incomplete (such as in first-degree atrioventricular block). However, an artificial pacemaker (see Figure: Keeping the Beat: Artificial Pacemakers) may be implanted in people who are at high risk of complete atrioventricular block (such as people with certain types of second-degree atrioventricular block or in people with third-degree atrioventricular block) to maintain the heart rate if complete heart block occurs.