Bradyarrhythmias, temporary and permanent pacing.

Bradycardia is common in critical care units. It may be transient, asymptomatic and of little consequence, or life-threatening. Bradycardia may result from abnormalities of the sinus node, atrioventricular node, or the His-Purkinje system. It may also be precipitated by drug effects or enhanced vagal tone. Proper diagnosis is pivotal to determining prognosis and management. Temporary and permanent pacing is now readily available, markedly improving the morbidity and mortality associated with bradyarrhythmias.