Question

Match the following Class and their Antiarrhythmic Drug:

• A. (1)-(P), (2)-(Q), (3)-(R), (4)-(S)
• B. (1)-(Q), (2)-(R), (3)-(S), (4)-(P)
• C. (1)-(R), (2)-(Q), (3)-(P), (4)-(S)
• D. (1)-(Q), (2)-(R), (3)-(P), (4)-(S)

Hint:

The Vaughan Williams classification helps in identifying antiarrhythmic agents by their primary mechanism and is essential in managing arrhythmias effectively.

Answer 1

The Correct Option is A

Antiarrhythmic drugs are classified based on the Vaughan Williams classification system into four main classes according to their primary mechanism of action: \begin{itemize} \item Class I – Sodium channel blockers. These drugs reduce the rate of rise of phase 0 of the action potential. Disopyramide, a Class Ia agent, falls under this category. (1)-(P)
\item Class II – Beta-adrenergic blockers. These reduce sympathetic activity, decrease heart rate, and conduction velocity. Metoprolol is a selective beta-1 blocker. (2)-(Q)
\item Class III – Potassium channel blockers. These prolong repolarization and the action potential duration. Amiodarone is a prototype agent. (3)-(R)
\item Class IV – Calcium channel blockers. These affect the SA and AV nodes, reducing conduction velocity. Verapamil is a non-dihydropyridine calcium channel blocker. (4)-(S)
\end{itemize} Matching accordingly: - (1)-(P) Disopyramide
- (2)-(Q) Metoprolol
- (3)-(R) Amiodarone
- (4)-(S) Verapamil