Antiarrhythmic Drugs Pharmacology MCQs with answer GPAT Questions

Antiarrhythmic Drugs Pharmacology MCQs with Answers

1. The pacemaker impulse is started in which portion of the cardiac conduction system?
a. Bundle of His
b. Purkinje fibres
c. Sinoatrial (SA) node
d. Atrioventricular (AV) node

2. The period of time in which another action potential cannot be initiated is called
a. phase 4 depolarization
b. action potential duration (APD)
c. effective refractory period (ERP)
d. maximum diastolic potential (MDP)

3. Which ion influx through “fast channels” is responsible for phase 0 depolarization?
a. K+
b. Na+
c. Ca++
d. Mg++

4. Which alteration in impulse conduction leads to atrial fibrillation?
a. Reentry
b. Heart block
c. Tachycardia
d. Fast response

5. Which is NOT a contributor to the ventricular tachyarrhythmia, torsades de pointes?
a. Short QT interval
b. Hypomagnesemia
c. Multiple waves of reentry
d. Selective K+ channel blocking drugs

6. Which is most likely to produce lupus-like adverse effects with long-term use?
a. Quinidine
b. Lidocaine
c. Procainamide
d. Disopyramide

7. Which class of antiarrhythmic drugs blocks K+ channels and delays phase 3 depolarization?
a. Class I
b. Class II
c. Class III
d. Class IV

8. Which drug is considered the prototype of class II antiarrhythmics?
a. Esmolol
b. Acebutolol
c. Metoprolol
d. Propranolol

9. Which class III antiarrhythmic drug may elicit changes in thyroid function?
a. Ibutilide
b. Bretylium
c. Dofetilide
d. Amiodarone

10. Which unique antiarrhythmic drug produces short-lived (seconds) therapeutic benefits and adverse effects?
a. Diltiazem
b. Verapamil
c. Adenosine
d. Magnesium