Which of the following is a characteristic of dihydropyridine calcium channel blockers?

Dihydropyridine calcium channel blockers are characterized by their potent vasodilatory effects. These medications, such as amlodipine and nifedipine, primarily work by selectively blocking calcium channels in vascular smooth muscle, which leads to relaxation of blood vessels and a decrease in systemic vascular resistance. This vasodilation results in lower blood pressure, making dihydropyridines useful in the management of hypertension and certain types of angina.

In contrast to dihydropyridines, non-dihydropyridine calcium channel blockers, like verapamil and diltiazem, have more significant effects on cardiac contractility and heart rate, particularly through their action on the AV node and other cardiac tissues. This is why they may be more commonly used to treat certain types of arrhythmias and can affect the heart rate more directly.

Thus, the defining trait of dihydropyridines is their ability to serve as potent vasodilators, primarily influencing blood vessel tension rather than directly altering cardiac contractility or heart rhythm.