Question 1

Which of the following choices are effects of digoxin on the heart?

Accepted Answer

Digoxin prolongs the refractory period of the AV node.By prolonging the refractory period of the AV node,fewer impulses will be transmitted to the ventricle,and the heart rate will fall.These effects are useful in the treatment of certain arrhythmias.Digoxin slows AV conduction and decreases the rate of the SA node.This effect is desired;however,an overdose may cause excessive slowing of the heart.The pulse must always be taken prior to administering a dose.The medication should not be given if the dose is below 60 beats per minute.

Question 2

Which of the following statements is true of heart failure?

Accepted Answer

If the left side of the heart fails,the blood backs up into the pulmonary circulation.Pulmonary edema results,producing dyspnea and orthopnea.The left side usually fails first.If the right side of the heart fails,then the right ventricle is unable to remove all the blood from the right side of the heart.Right-sided heart failure causes systemic congestion.Symptoms include peripheral edema,with fluid accumulation evidenced by pitting edema.

Question 3

Which of the following classes of antiarrhythmics is associated with gingival enlargement?

Accepted Answer

Calcium channel blockers and phenytoin are associated with gingival enlargement.Verapamil is the most reported calcium channel blocker associated with gingival enlargement.Amiodarone is associated with liver toxicity,blue skin discoloration,and photosensitivity.Disopyramide is associated with anticholinergic xerostomia.Procainamide is associated with a reversible lupus erythematosus-like syndrome,CNS depression,and xerostomia.

Question 4

MI refers to

Accepted Answer

Myocardial infarction (MI)is an occlusion or blockage of arteries supplying the muscles of the heart,resulting in injury or necrosis of the heart muscle (heart attack).Transient lack of oxygen to the heart is myocardial ischemia.Myocardial infarction does not refer to CHF,which is a chronic condition,or abnormal sinus rhythm of the heart.

Question 5

The cells of cardiac muscles have an intrinsic rhythm called

Accepted Answer

The intrinsic rhythm is called automaticity."Pacemaker" cells spontaneously produce action potentials as they undergo slow spontaneous depolarization during diastole.If any heart muscle cell is left undisturbed and isolated from the rest of the heart with appropriate nutrients and oxygen,each cell will beat spontaneously at its own rate.The intrinsic rhythm of cardiac muscle is not called spontaneity,anarchy,or hierarchy.

Question 6

Hypersalivation is a sign of toxicity for which of the following agents?

Accepted Answer

Early signs of digoxin toxicity include anorexia,nausea and vomiting,and copious salivation.A reduction in the dose level of digoxin usually alleviates these adverse reactions.None of the other choices cause hypersalivation as a sign of toxicity.Clonidine is most likely to cause xerostomia and enalapril the least likely (oral manifestations include dry cough and dysgeusia).Nifedipine and hydrochlorothiazide can produce mild to moderate xerostomia.

Question 7

The use of nitroglycerin (NTG)is contraindicated if sildenafil (Viagra)has been administered within 24 hours.This is because the NTG-sildenafil combination can precipitate a hypertensive crisis.

Accepted Answer

Taking NTG within 24 hours of sildenafil is contraindicated.NTG is contraindicated,however,because the combination can cause dangerously low blood pressure (hypotension)rather than hypertension.Sildenafil citrate (Viagra)is a vasodilator that potentiates the vasodilating effects of nitrates.It is contraindicated in persons taking organic nitrates or nitrates such as nitroglycerin,because it may have serious or even fatal effects if the patient has cardiac decompensation.

Question 8

Nitroglycerine (NTG)is a(n)_____ that produces relaxation of vascular smooth muscle throughout the body.

Accepted Answer

NTG produces a systemic relaxation of vascular smooth muscle.Indirectly,there is a reduction in work of the heart produced by the effect on both the venous and the arterial sides of the circulation.By reducing workload on the heart,NTG decreases the oxygen demand with relief or reduction of angina pain.NTG does not belong to the remaining categories of drugs.

Question 9

A patient has a cardiovascular disorder for which a physician prescribes a local anesthetic drug.What might this cardiovascular disorder be?

Accepted Answer

Local anesthetic agents such as procainamide and lidocaine block Na⁺ channels in the heart and depress parts of the heart that are beating abnormally.Local anesthetic agents are not used in the treatment of coronary artery disease,hypertension,or angina pectoris.

Question 10

Dental patients with left heart failure may need to be positioned in the dental chair

Accepted Answer

Full-reclining position may precipitate dyspnea or orthopnea (breathing difficulty experienced while lying flat).Elevation of one hip is indicated for some pregnant women requiring dental treatment during their third trimester.Lying in a flat position or with feet elevated above the head could precipitate orthopnea.

Question 11

Nitroglycerine (NTG)is used for what cardiovascular disease?

Accepted Answer

NTG is a compound that releases nitrite and nitric oxide.These are very strong dilators to veins and arteries.This reduces workload to the heart and can reverse an anginal episode.NTG is not used for atherosclerosis,coronary artery disease,or arrhythmias.

Question 12

Which of the following is true concerning what research has shown regarding the relationship between periodontal disease and cardiovascular disease?

Accepted Answer

Studies both support and reject the relationship between periodontal disease and cardiovascular disease.Researchers and government agencies continue to investigate the possible relationship between periodontal disease and cardiovascular disease.Researchers do agree that more studies are needed.Studies have been controversial,showing both a relationship and no relationship between periodontal disease and cardiovascular disease.

Question 13

To prevent tolerance,prophylactic nitrates should be given with at least a(n)

Accepted Answer

Prophylactic nitrates should be given with at least an 8- to 12-hour "vacation" every day.The mononitrate dose form requires a 7-hour "vacation" daily;the first dose is given in the morning and the second dose is given 7 hours later.The "vacation" is taken in order to prevent tolerance.With long-term regular use,tolerance develops to the effects of nitrates.In fact,no difference can be detected between a long-acting nitrate and placebo when taken without a daily "vacation."

Question 14

How long should a person who has had a myocardial infarction wait before receiving dental care?

Accepted Answer

Patients who have suffered a myocardial infarction should wait 6 months before receiving any type of oral health care in order to give the heart a chance to heal.Bacteria from the mouth can enter the bloodstream and weaken an already weakened heart.If oral health care is necessary prior to the 6-month time period,one should consult with the patient's cardiologist or general practitioner to determine whether or not the patient's heart has healed sufficiently.The amount of time to wait prior to receiving dental care is specifically stated.

Question 15

Nitroglycerin (NTG)should be

Accepted Answer

The dental team should be prepared to treat an acute anginal attack before treating any patient with a history of angina.The patient's personal NTG tablets or spray should be available and placed on the bracket table in case of an acute attack.The office should have some NTG in their emergency kit as well.NTG is degraded by heat,moisture,and by light.It should be stored in its original brown glass container and tightly closed,because it can be adsorbed by plastic.It should not be refrigerated because condensation of the moisture in the air produces moisture that can reduce its effectiveness.In the case of an attack,NTG should be administered only three times within 15 minutes.If three tablets do not stop the anginal attack,the patient should be taken immediately to the emergency room with a member of the dental team or an emergency medical expert.

Question 16

The _____ has the fastest rate of depolarization and therefore directs all the other cells of the heart.

Accepted Answer

The SA node has the fastest rate of depolarization and therefore directs all the other cells of the heart.It normally fires impulses approximately 80 times per minute.The SA node is innervated by both the parasympathetic nervous system and the sympathetic nervous system.The SA node sends a message to the AV node via the atrial muscle.The AV node sends the message via the bundle of His to the Purkinje fibers.The Purkinje fibers then send the message to the cardiac muscle cells,to the apex of the ventricles,directing them all to contract as they get the message.

Question 17

Which of the following is the primary type of drug recommended for patients who have edema or fluid retention with heart failure (HF)?

Accepted Answer

Most patients with HF have edema or fluid retention.Diuretics are used in these patients to relieve the symptoms of HF.The American College of Cardiology and the American Heart Association recommend that all patients who have evidence of fluid retention and for most patients with a history of fluid retention be prescribed a diuretic.Diuretics should be combined with angiotensin-converting enzyme inhibitors,beta-blockers,angiotensin receptor antagonists,or aldosterone antagonists.

Question 18

In a normally functioning heart,the bundle of His receives its electrical input from the

Accepted Answer

The AV node sends the message to the Purkinje fibers via the bundle of His.The direction of flow of the impulses to the excitable tissues of the heart is the SA node,AV node,bundle of His,Purkinje fibers,and cardiac muscle.The bundle of His is between the AV node and the Purkinje fibers.

Question 19

Each of the following conditions is an absolute contraindication to dental treatment until a consultation with the patient's medical provider has determined any special treatment alterations that might be warranted except one.Which is the exception?

Accepted Answer

Chronic,stable angina is not a contraindication to dental treatment.According to the most current ACC/AHA guidelines,the primary goals of therapy for a patient with chronic,stable angina are to prevent a myocardial infarct and death and to completely or nearly completely eliminate ischemic symptoms.Unstable or recent onset of angina pectoris,uncontrolled heart failure,uncontrolled arrhythmias,and significant,uncontrolled hypertension are all cardiovascular contraindications to dental treatment.

Question 20

Which of the following categories of drug is the best choice to relieve the acute symptoms of angina?

Accepted Answer

Nitroglycerin (NTG)is by far the most often used nitrate for the management of acute anginal episodes.NTG is also used to prevent anginal attacks induced by stress or exercise.Nitro-Bid is a long-acting nitrate for prophylactic use.Propranolol is a beta-blocker for prophylactic use.Verapamil and nifedipine are calcium channel blockers for prophylactic use as well.

Quiz 12: Drugs for the Treatment of Cardiovascular Disease