What effect do calcium channel blockers have on systemic vascular resistance?

Calcium channel blockers are medications that primarily work by inhibiting the influx of calcium ions into smooth muscle cells and cardiac muscle cells. This action leads to relaxation of the vascular smooth muscle, resulting in vasodilation, or widening of the blood vessels. When blood vessels dilate, systemic vascular resistance decreases because there is more space for the blood to flow, which lowers the overall resistance that the heart has to work against to pump blood throughout the body.

By decreasing systemic vascular resistance, calcium channel blockers can effectively lower blood pressure and improve blood flow. This mechanism is particularly beneficial in conditions such as hypertension and certain types of angina. The choice indicating that they decrease systemic vascular resistance accurately captures their primary effect on the cardiovascular system.