Class II antiarrhythmics

Class II antiarrhythmics

ß-blockers are the class II antiarrhythmics. They act by selectively blocking the effects of catecholamines at the β1 adrenergic receptors (reducing the sympathetic activity), thereby decreasing heart rate, delaying conduction, and decreasing automacy of the pacemaker cells as result. Various tachycardias can be treated with class II antiarrhythmic drugs. β-blockers are antagonists for the β-adrenergic receptors in the heart. β-blockers are drug of choice in the treatment of arrhythmias with an adrenergic origin.Common antiarrhythmic

β-blockers are metoprolol, bisoprolol, and atenolol. Sotalol is also a ß-blocker but also has Class III antiarrhythmic effects. For more details on β-blockers, see the section on β-blockers.


β-blockers inhibit the formation of the impulses in the SA node by:


Addition of propranolol to the drug regimen of a patient receiving lidocaine for premature ventricular contractions after a myocardial infarction results in:


Which one is a nonselective β-blocker which slows heart rate and also prolongs action potential duration by blocking transmembrane potassium currents?


Antiarrhythmic treatment with β-blockers is typically aimed at