What is the effect of cholinesterase inhibitors on heart rate?

Cholinesterase inhibitors are medications that block the action of the enzyme cholinesterase, which is responsible for breaking down acetylcholine in the synaptic cleft. By inhibiting this enzyme, these drugs lead to an accumulation of acetylcholine, enhancing its effects on both the central and peripheral nervous systems.

In the context of heart rate, the vagus nerve, which is part of the parasympathetic nervous system, releases acetylcholine at the heart's atrioventricular node and sinoatrial node. When cholinesterase inhibitors are administered, the resulting increased acetylcholine levels enhance vagal tone, thereby exerting a negative chronotropic effect, which slows the heart rate. This effect is significant in conditions where there is a need to manage heart rate, such as in certain types of arrhythmias or in the treatment of myasthenia gravis.

Thus, cholinesterase inhibitors lead to a decrease in heart rate, making the answer to this question accurate.