This set of pharmacology MCQs on vasodilators and inotropics has been developed by the Dept. Of Pharmacology at UMKC School of Medicine.
Item Number: 9623 correct answer: 5 category: Inotropes/Vasodilators
1. Digitalis glycosides slows the heart rate in patients with systolic
dysfunction as a result of all of the following EXCEPT:
1. direct action of digitalis on the AV node to slow conduction
2. indirect effect of enhanced vagal tone on AV node
3. enhanced parasympathetic outflow from the CNS through an indirect
mechanism
4. diminished sympathetic tone which is high as a compensatory mechanism in
heart failure
5. enhanced responsiveness of the SA and AV node to norepinephrine through
an indirect mechanism
Item Number: 11356 correct answer: 1 category: Inotropes/Vasodilators
2. Which of the following drug-mechanism of action pairs is properly matched?
1. digoxin – inhibits Na+ – K+ ATPase pump
2. dobutamine – inhibits troponin I
3. amrinone – inhibits troponin I
4. dopamine – inhibits troponin I
5. isoproterenol – inhibits 1 and 2 receptorsItem Number: 1161 correct answer: 2 category: Inotropes/Vasodilators
3. The rapid heart rate sometimes seen after nitroglycerin administration is best
explained by:
1. a direct positive chronotropic effect on the myocardium
2. reflex sympathetic discharge due to a fall in systemic blood pressure
3. the ability of nitroglycerin to release norepinephrine from sympathetic
nerve endings
4. a decrease in intracranial pressureItem Number: 1158 correct answer: 3 category: Inotropes/Vasodilators
4. The effectiveness of digitalis in the treatment of atrial flutter is primarily
due to its ability to:
1. slow the rate of firing of the S-A node
2. exert an atropine-like effect on the A-V node
3. slow conduction through the A-V node
4. decrease the refractory period through the A-V node
5. decrease the rate of conduction through atrial muscleItem Number: 3828 correct answer: 5 category: Inotropes/Vasodilators
5. When digitalis therapy is initiated, serious cardiac arrhythmias may be caused
by a deficiency of:
1. Na+
2. K+
3. Cl-
4. Mg++
5. 2,4Item Number: 3961 correct answer: 3 category: Inotropes/Vasodilators
6. The cardiac glycosides are used in the treatment of congestive heart failure
and atrial fibrillation. Given the differences between the cardiac glycosides
in their length of action and organs of major excretion, the correct statement
concerning the use of digitoxin is:
1. gastrointestinal absorption of digitoxin is incomplete and highly
variable within patients
2. digitoxin is excreted primarily unchanged in the kidney with a half life
of about 24 hours
3. digitoxin is highly protein bound in the serum
4. digitoxin has a much higher incidence of toxicity in patients with renal
disease
5. digitoxin is only available as an oral preparationItem Number: 11384 correct answer: 4 category: Inotropes/Vasodilators
7. Digitalis toxicity manifested by premature ventricular contractions maybe
treated with all of the following EXCEPT:
1. lidocaine
2. digitalis-specific immune FAB antibody
3. phenytoin
4. quinidine
5. All are correctItem Number: 11359 correct answer: 2 category: Inotropes/Vasodilators
8. The correct statement regarding digitalis is:
1. in normal individuals, digitalis increases cardiac output
2. in normal individuals, digitalis increases myocardial oxygen consumption
3. in normal individuals, digitalis reduced total peripheral resistance in
response to enhanced myocardial contractility
4. in normal individuals, digitalis depresses myocardial contractility
5. in normal individuals, digitalis increases heart rateItem Number: 3718 correct answer: 1 category: Inotropes/Vasodilators
9. A routine electrocardiogram reveals a borderline delay in PR interval, sagging
left ventricular ST segments and a shortened RT interval. The most likely
explanation would be:
1. digitalis effect
2. acute sub-endocardial ischemia
3. hypokalemia
4. hypocalcemia
5. myxedemaItem Number: 11367 correct answer: 4 category: Inotropes/Vasodilators
10. An uncommon cardiac manifestation of digitalis toxicity is:
1. premature ventricular contractions
2. second and third degree heart block
3. atrio-ventricular junctional escape beats
4. atrial fibrillation with rapid ventricular response
5. All are correctItem Number: 4751 correct answer: 2 category: Inotropes/Vasodilators
11. The most widely used digitalis glycosides in the United States are digoxin and
digitoxin. The half-life (t1/2) of digitoxin is approximately:
1. 1 day
2. 7 days
3. 12 days
4. dependent upon the route of administration
5. dependent upon renal functionItem Number: 119 correct answer: 1 category: Inotropes/Vasodilators
12. The maintenance dose of digoxin is primarily dependent upon:
1. renal function
2. sex, hepatic function and protein level
3. pulmonary function
4. the loading dose and the type of diuretic being used
5. level of serum potassiumItem Number: 11408 correct answer: 4 category: Inotropes/Vasodilators
13. Thiocyanate toxicity is a potential adverse effect associated with:
A. amrinone
B. nitroglycerin
C. milrinone
D. nitroprusside
1. A,B,C
2. A,C
3. B,D
4. D only
5. All are correctItem Number: 2722 correct answer: 4 category: Inotropes/Vasodilators
14. A 42-year-old white male with rheumatic mitral insufficiency is seen with
symptoms and findings of initial left ventricular failure. You give him
digitalis and recall that all of the following are pharmacologic effects of
digitalis EXCEPT:
1. decreases conduction velocity in the A-V node
2. increases the effects of normal vagal activity of the heart
3. shortens the effective refractory period of the Purkinje fibers
4. weakens myocardial contractility
5. prolongs the functional refractory period of the A-V nodeItem Number: 1193 correct answer: 3 category: Inotropes/Vasodilators
15. Orthostatic hypotension is most likely to occur following the use of:
1. phenylephrine
2. reserpine
3. amyl nitrite
4. metaraminol
5. tetrahydrozolineItem Number: 4600 correct answer: 2 category: Inotropes/Vasodilators
16. The chemical configuration of a molecule may determine its degree of
absorption, its distribution, and its route of metabolism. Structurally, the
digitalis glycosides resemble:
1. catecholamines
2. steroids
3. salicylates
4. nitrofurantoin
5. phenothiazinesItem Number: 13697 correct answer: 3 category: Inotropes/Vasodilators
17. All of the following are actions of nitrates in angina pectoris EXCEPT:
1. reflex increase in heart rate
2. ventricular size decrease
3. ejection fraction increased
4. peripheral venous pooling–decrease in preload
5. systolic blood pressure decreaseItem Number: 11398 correct answer: 4 category: Inotropes/Vasodilators
18. The sympathomimetic which may promote diuresis by a direct effect on the
kidney is:
1. isoproterenol
2. dobutamine
3. norepinephrine
4. dopamine
5. epinephrineItem Number: 13704 correct answer: 4 category: Inotropes/Vasodilators
19. Nitroglycerin administered sublingually reduces venous tone, causing pooling
of blood in peripheral veins and lowers peripheral arterial resistance,
resulting in a decline in blood pressure. Both end-diastolic and end-systolic
dimensions of the left ventricle are reduced; therefore myocardial oxygen
needs are decreased primarily by a reduction of:
1. blood pressure
2. heart rate
3. coronary vascular resistance
4. intramyocardial tension
5. sulfhydryl bondsItem Number: 8090 correct answer: 3 category: Inotropes/Vasodilators
20. Digitalis must be used with caution in patients with acute myocardial
infarction. Which of the following is true of digitalis use?
A. in normal hearts, it increases contractility and myocardial O2
consumption
B. it is recommended in uncomplicated myocardial infarction
C. in failing hearts, it decreases or leaves unchanged myocardial O2
consumption
D. in acute myocardial infarction, patients are less sensitive to the
development of arrhythmias due to digitalis toxicity
1. A only
2. A,B,C
3. A,C
4. B,D
5. D onlyItem Number: 1160 correct answer: 3 category: Inotropes/Vasodilators
21. Digitalis may slow the heart rate by:
1. blocking the activity of the carotid and aortic arch baroreceptors
2. exerting an atropine-like effect on the A-V node
3. stimulation of vagal center in the medulla to increase efferent firing
4. increasing the rate of conduction through the A-V node
5. None of the aboveItem Number: 11412 correct answer: 4 category: Inotropes/Vasodilators
22. Compared to digitoxin, digoxin is or has:
1. more highly protein-bound
2. more extensive enterohepatic circulation
3. prolonged elimination half-life
4. less completely absorbed orally
5. more extensively hepatically clearedItem Number: 11390 correct answer: 4 category: Inotropes/Vasodilators
23. The beneficial effects of digitalis are derived from its effect on myocardial
contractility and on myocardial conduction and excitability. In therapeutic
doses, digitalis:
1. slows the atrial rate in atrial fibrillation
2. enhances atrioventricular conduction
3. slows the atrial rate in sinus tachycardias
4. slows the ventricular rate in atrial fibrillation
5. decreases ventricular automaticityItem Number: 4696 correct answer: 3 category: Inotropes/Vasodilators
24. Digitalis-induced emesis is:
1. only seen when digoxin is given orally
2. of no true clinical importance
3. due to stimulation of the chemoreceptor trigger zone
4. related to Na+ K+ ATPase inhibition within the GI tract
5. commonly seen with rapid parenteral administrationItem Number: 4593 correct answer: 4 category: Inotropes/Vasodilators
25. Digitalis has a beneficial effect on the failing myocardium via its action to
increase the availability of calcium to the contractile machinery. As with
many drugs, digitalis has also been overused. The correct statement
concerning the use of digitalis in the ischemic and non-ischemic myocardium
is:
1. there is a net increase in oxygen consumption in the non-failing
myocardium
2. there is a net increase in oxygen consumption in the failing dilated
myocardium
3. digitalis has proven value in prophylaxis for diastolic dysfunction
4. digitalis causes vasoconstriction in the normal heart secondary to
enhanced sympathetic outflow and blocking the Na+-K+ ATPase in smooth
muscle
5. digitalis causes an increase in heart rate in the normal heart