Bradycardia is an especially slow heartbeat and a risk factor for fainting and other health problems. Atropine, an anticholinergic medication (a drug that blocks the neurotransmitter acetylcholine ...

sinus bradycardia, sinoatrial block, and alternating episodes of tachycardia and bradycardia. [1] A large proportion of SND patients also have atrial fibrillation (AF) and prolonged sinus pauses ...