Antiarrhythmic Drugs

1. Ventricular arrhythmia followed myocardial infarction of a patient. Cardiac rhythm was normalized by the introduction of anthiarrhythmic drug with local anesthesia effect. What drug was introduced?

*A. Lidocaine

B. Anaesthesinum

C. Verapamilum

D. Pananginum

E. Propranolol

2. A 45-year-old patient has diagnosis of ciliary arrhythmia and essential hypertension. What drug is necessary to prescribe for this patient for prevention of attacks of arrhythmia?

*A. Propranolol

B. Sustac-forte

C. Potassium chloride

D. Strophantinum

E. Lidocaine

3. A 55-year-old patient with continuing ventricular arrhythmias was admitted to the hospital. The patient is taking timolol drops for glaucoma, daily insulin injections for diabetes mellitus, and ACE inhibitor for hypertension. You have decided to use phenytoin instead of procainamide. What is the reason?

*A. The anticholinergic effect of procainamide would aggravate glaucoma

B. The local anesthetic effect of procainamide would aggravate the hypertension

C. The local anesthetic effect of procainamide would potentiate diabetes

D. The hypertensive effect of procainamide would aggravate the hypertension

E. The cholinergic effect of procainamide would aggravate the diabetes

4. In patient who has had attacks of paroxysmal atrial tachycardia, an ideal prophylactic drug is:

*A. Verapamil

B. Procainamide

C. Lidocaine

D. Nifedipine

E. Adenosine

5. Which of the following is an antiarrhythmic agent that has relatively few electrophysiologic effects on normal myocardial tissue but suppresses the arrhythmogenic tendencies of ischemic myocardial tissues?

*A. Lidocaine

B. Procainamide

C. Quinidine

D. Propranolol

E. Disopyramide

6. A 59-year-old male with a history of rheumatic heart disease is found to have atrial fibrillation, for which he is treated with digoxin. Treatment with digoxin converts his atrial fibrillation to a normal sinus rhythm and most likely results in a decrease in which of the following?

*A. The conduction velocity in the atrioventricular node

B. The velocity of shortening of the cardiac muscle

C. The lenght of the refractory period

D. The atrial maximum diastolic resting potential

Digoxin is used in AF to slow the ventricular rate, not usually the AF itself. Digoxin acts to slow the speed of conduction, increase the atrial and AV nodal maximal diastolic resting membrane potential, and increase the effective refractory period in the AV node, which prevents transmission of all impulses from the atria to the ventricles. It exerts these effects by acting directly on the heart and by indirectly increasing vagal activity.

7. 62-year-old patient with chronic heart failure and atrial tachyarrhythmia takes simultaneously quinidine and digoxin. If these drugs are administered concurrently, which of the following influence does quinidine have on digoxin?

*A. The concentration of digoxin in the plasma is increased

B. The metabolism of digoxin is prevented

C. The absorption of digoxin from the gastrointestinal tract is decreased

D. The effect of digoxin on the atrioventricular node is antagonized

E. The ability of digoxin to inhibit the Na⁺,K⁺-stimulated ATPase is reduced

8. Patients with genetically low levels of N-acetyltransferase are more prone to develop a lupus erythematosus-like syndrome with which of the following drug?

*A. Procainamide

B. Propranolol

C. Digoxin

D. Captopril

E. Lidocaine

9. The first-line drug for treating an acute attack of reentrant supraventricular tachycardia is:

*A. Adenosine

B. Digoxin

C. Propranilol

D. Mesatonum

E. Edrophonium

10. A 36-year-old male is seen in the emergency department with tachycardia, a respiratory rate of 26 breaths per minute, and EKG evidence of an arrhythmia. An intravenous bolus dose of an antiarrhythmic agent is administered, and within 30s, he has a respiratory rate of 45 breaths per minute and complains of a burning sensation in his chest. Select the drug most likely to have caused these adverse effects.

*A. Adenosine

B. Digoxin

C. Dobutamine

D. Lidocaine

E. Nifedipine

11. A 68-year-old female has atrial fibrillation, which is treated with an antiarrhythmic agent that blocks Na⁺ channels. On a recent office visit, she complained of recurrent attacks of feeling faint and of experiencing an episode of loss of consciousness. An EKG should marked prolongation of the QT interval. Plasma concentration of the drug was in the therapeutic range. Select the drug most likely to have caused these adverse effects.

*A. Quinidine

B. Amiodarone

C. Bretylium

D. Adenosine

E. Verapamil

12. A 55-year-old male has recurrent ventricular arrhythmias after an myocardial infarction, for which he is given an antiarrhythmic agent that blocks Na⁺ channels and prolongs the action potential. One year later, a blood test is positive for circulating antinuclear antibodies. Select the drug which most likely to have caused this phenomenon.

*A. Procainamide

B. Amiodarone

C. Adenosine

D. Sotalol

E. Verapamil

13. 24 hours after an acute myocardial infarction, a 46-year-old male is being treated with a continuous intravenous drip of an antiarrhythmic drug to suppress frequent multifocal premature ventricular contractions. He develops generalized seizure activity. The seizure activity can be most readily explained by:

*A. Lidocaine toxicity

B. Systemic embolization

C. Systemic hypotension

D. Ventricular tachycardia

E. Ventricular asystole

14. False statement concerning use of calcium antagonists as antiarrhythmics:

*A. Verapamil, diltiazem, and nifedipine all exert equally effective antiarrhythmic actions

B. Slows conduction velocity through the atrio-ventricular node and increases functional refractory period

C. Useful for slowing ventricular rate in atrial fibrillation

D. Hypotension may be a limiting side effect

E. Slows inward calcium current thereby decreasing the rate of spontaneous phase 4 depolarization in Purkinje fibers

15. Although most antiarrhythmic drugs (and indeed most drugs) are chemically synthesized, some compounds that occur endogenously in humans are useful. Indicate which of the following agents occurs endogenously and is a useful antiarrhythmic agent.

*A. Adenosine

B. Digoxin

C. Phenitoin

D. Quinidine

E. Lidocaine

16. Which of the following calcium channel blockers would be most likely to suppress atrial tachyarrhythmias involving the AV-node?

*A. Verapamil

B. Nifedipine

C. Nicardipine

D. Amlodipine

E. Diltiazem

17. Which of the following statements is incorrect?

*A. Lidocaine is used mainly for atrial arrhythmias

B. Lidocaine must be given parenterally

C. Procainamide is associated with a reversible lupus phenomenon

D. Quinidine is active orally

E. All antiarrhythmic drugs can suppress cardiac contractions

18. The bronchoobstructive syndrome appeared in patient during the treatment of ciliary arrhythmia. What antiarrhythmic drug can cause such complication?

*A. Propranolol

B. Aimalinum

C. Nifedipinum

D. Verapamilum

E. Novocainamidum

19. A patient with myocardial infarction and cardiac insufficiency has ventricular arrhythmia. What antiarrhythmic agent is a drug of choice in this case?

*A. Lidocainum

B. Chinidini sulfas

C. Verapamilum

D. Novocainamidum

E. Disopiramidum

20. The drug was been prescribed to 56-year-old patient who suffers from ischemic heart disease with atrial extrasystoles. It is known, that drug blocks K⁺ channels, decreases the adrenergical influence upon the heart, significantly increases the duration of action potential, and dilates the coronary vessels. What drug was been prescribed?

*A. Amiodarone

B. Corglycon

C. Nitroglycerin

D. Dobutamine

E. Lisinopril

21. In experiment on the heart muscle the antiarrhythmic agent lowered excitability of cardiomyocytes, not influencing on the action potential form. Identify this agent.

A. * Lidocaine

B. Novocainamide

C. Verapamil

D. Chinidinum

E. Amiodaronum