Editing Antiarrhythmic agent (section)

===Class IV agents===
Class IV agents are slow [[Calcium channel blocker#Non-dihydropyridine|non-dihydropyridine]] [[calcium channel blocker]]s. They decrease conduction through the [[AV node]], and shorten phase two (the plateau) of the [[cardiac action potential]]. They thus reduce the contractility of the heart, so may be inappropriate in heart failure. However, in contrast to beta blockers, they allow the body to retain adrenergic control of heart rate and contractility.{{cn|date=March 2023}}

Class IV agents include [[verapamil]] and [[diltiazem]].