cardiovascular disorders
Medications for Arrhythmias
Class IV Antiarrhythmic Drugs
Class IV drugs are Nondihydropyridine calcium channel blockers These drugs depress calcium-dependent action potentials in slow-channel tissues and thus decrease the rate of automaticity, slow conduction velocity, and prolong refractoriness. Heart rate is slowed, the PR interval is lengthened, and the AV node transmits rapid atrial depolarizations at a lower frequency. These drugs are used primarily to treat Reentrant Supraventricular Tachycardias (SVT) Including Wolff-Parkinson-White Syndrome . They may also be used to slow the ventricular response rate to 