Which effect does Verapamil primarily produce?

Verapamil primarily produces a negative chronotropic and negative inotropic effect on the heart. This means that it decreases both the heart rate (chronotropy) and the force of contraction (inotropy).

As a calcium channel blocker, Verapamil inhibits calcium influx into cardiac and smooth muscle cells. In the heart, this leads to a reduction in the excitability of the sinoatrial (SA) node, which is responsible for initiating the heartbeat. Therefore, the negative chronotropic effect reflects a decrease in heart rate, which is particularly beneficial in conditions such as tachycardia where the heart is beating too fast.

In terms of inotropic effects, Verapamil lowers the force of cardiac contraction. This is significant because reduced contractility can help prevent excessive workload on the heart, especially in conditions such as hypertension or heart failure, where managing the heart's workload is crucial for patient health.

Overall, these effects support Verapamil's use in treating arrhythmias and other cardiovascular conditions, making it important for managing heart rate and contractility effectively.