Multifocal atrial tachycardia.

Multifocal atrial tachycardia is typically seen in elderly patients with severe illnesses, most commonly COPD. The mechanism of the arrhythmia may be delayed afterdepolarizations leading to triggered activity, but this has not been firmly established. The initial treatment of multifocal atrial tachycardia should include supportive measures and aggressive reversal of precipitating causes. Since multifocal atrial tachycardia is commonly a secondary phenomenon, the role for antiarrhythmic therapy is unclear. Metoprolol, magnesium, and verapamil have been evaluated in a few treatment studies, and may have a role in the treatment of multifocal atrial tachycardia.