Can you explain a little about how Calcium channel blockers and Ranolazine work in the body and why they work please?

Calcium transients are an essential mechanism in muscle cell contractile function. Calcium channel blockers reduce the tone of vascular smooth muscle cells, resulting in vasodilation and reduced resistance to flow and in the prevention of hypercontraction in response to stimuli.

Ranolazine is a metabolic modulator that favours cell utilisation of glucose instead of free fatty acids in ATP synthesis.