Heart block in general is the delayed or absent conduction through the atrioventicular node (the communication point between the upper and lower chambers of the heart). The most likely underlying causes include alterations in the nervous influence in this area or fibrous replacement tissue in this location although electrolyte abnormalities, some medications, and inflammatory processes can cause this as well. Alterations in nervous influence are typically due to another disease process like diseases of the nervous system, respiratory system, or gastrointestinal system and are not a primary cardiac issue. If the heart block is due to a primary cardiac issue then the treatment depends on the severity of the condition. If the heart block is causing symptoms (decreased energy level or fainting episodes) then the treatment of choice is to place a permanent pacemaker to control the heart rhythm and alleviate these symptoms. See pacemaker implantation. If a permanent pacemaker is not an option, then medical management options can be considered although they are often less successful than pacemaker therapy.