Atrioventricular Block Medication
- Author: Chirag M Sandesara, MD, FACC; Chief Editor: Jeffrey N Rottman, MD more...
Medication Summary
Long-term medical therapy is not indicated in atrioventricular (AV) block. Permanent pacing is the therapy of choice in advanced AV block, and it does not require concomitant medical therapy. Sometimes AV nodal blocking medications that contribute to heart block can be discontinued if not necessary. Atropine administration (0.5-1.0 mg) or isoproterenol infusion may improve AV conduction in emergencies where bradycardia is caused by a proximal AV block (located in the atrioventricular node [AVN]) but may worsen conduction if the block is in the His-Purkinje system.
Anticholinergic Agents
Class Summary
The goal of administering anticholinergic agents is to improve conduction through the AVN by reducing vagal tone via muscarinic receptor blockade. This is only effective if the site of block is within the AVN. For patients with suspected infranodal block, this therapy is ineffective and may make the level of the block worse if it is in the His bundle or below.
Atropine IV/IM (Atropair, Atropisol)
Atropine increases AV conduction. An insufficient dose may cause paradoxical slowing of the heart rate.
Isoproterenol (Isuprel)
Isoproterenol has beta1- and beta2-adrenergic receptor activity. It binds the beta-receptors of the heart, smooth muscle of bronchi, skeletal muscle, the vasculature, and the alimentary tract. It has positive inotropic and chronotropic actions.
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