Complete failure of conduction from atria to ventricles; atria and ventricles depolarize independently (See Fig. 122-1C). May occur with MI, digitalis toxicity, or degenerative conduction system disease. Permanent pacemaker is usually indicated, except when reversible (e.g., drug-related or appears only transiently in MI without associated bundle branch block).
For a more detailed discussion, see Spragg DD, Tomaselli GF: The Bradyarrhythmias: Disorders of the Sinoatrial Node, Chap. 274, p. 1466; and Chap. 275, and Spragg DD, Tomaselli GF: The Bradyarrhythmias: Disorders of the Atrioventricular Node, p. 1470, in HPIM-19. |