What effect does hyperkalemia generally have on heart rate?

Hyperkalemia, which is an elevated level of potassium in the bloodstream, has a significant impact on the cardiovascular system, particularly on heart rate. Increased potassium levels can interfere with the normal electrical activity of the heart. Specifically, hyperkalemia leads to a decrease in the resting membrane potential of cardiac cells, making them less excitable.

As potassium levels rise, the heart's electrical conduction can become impaired. This impairment can manifest in several ways, including reduced heart rate or bradycardia, due to the decreased effectiveness of electrical impulses that control heart rhythm. The condition can also lead to more severe complications such as arrhythmias, which can further result in a decreased heart rate.

In summary, hyperkalemia typically decreases heart rate by affecting the heart's electrical conduction system, making it a critical condition that requires careful monitoring and management.