Why are Verapamil and Diltiazem considered to be antidysrhythmic medications but Nifedipine is not, if all three medications are calcium channel blockers?

Nifedipine is a dihydropyridine and therefore only affects the movement of calcium into the cells of vascular smooth muscle.

Verapamil and Diltiazem affect the movement of calcium into the cells of both the heart and blood vessels.

All three medications have antidysrhythmic properties.

Nifedipine affects the movement of calcium into the cells of both the heart and blood vessels.