MCQs framed from High yield areas of Anti-anginal Pharmacology

(A) Decreased heart rate (B) Decreased venous capacitance Mr. Green, 60 years old, has severe chest pain when he attempts to carry parcels up stairs to his apartment. The pain rapidly disappears when he rests. A decision is made to treat him with nitroglycerin. 1. Nitroglycerin, either directly or through reflexes, results in which one of the following effects? (A) Decreased heart rate (B) Decreased venous capacitance (C) Increased afterload (D) Increased cardiac force (E) Increased diastolic intramyocardial fiber tension Nitroglycerin increases cardiac force because the decrease in blood pressure evokes a compensatory increase in sympathetic discharge. The answer is (D).

(A) Meningeal vasodilation (B) Reflex tachycardia Mr. Green, 60 years old, has severe chest pain when he attempts to carry parcels up stairs to his apartment. The pain rapidly disappears when he rests. A decision is made to treat him with nitroglycerin. In advising Mr. Green about the adverse effects he may notice, you point out that nitroglycerin in moderate doses often produces certain symptoms. These toxicities result from all of the following EXCEPT (A) Meningeal vasodilation (B) Reflex tachycardia (C) Increased cardiac force (D) Methemoglobinemia (E) Sympathetic discharge Methemoglobinemia never occurs from the doses of nitroglycerin (or other nitrates) used to treat angina. The nitrites (in large doses) cause methemoglobinemia. The answer is (D).

(D) Sublingual isosorbide dinitrate (E) Sublingual nitroglycerin Mr. Green, 60 years old, has severe chest pain when he attempts to carry parcels up stairs to his apartment. The pain rapidly disappears when he rests. A decision is made to treat him with nitroglycerin . Two years later, Mr. Green returns complaining that his nitroglycerin works well when he takes it for an acute attack but that he is having frequent attacks now and would like something to prevent them. Useful drugs for the prophylaxis of angina of effort include which one of the following? (A) Amyl nitrite (B) Diltiazem (C) Esmolol (D) Sublingual isosorbide dinitrate (E) Sublingual nitroglycerin The calcium channel blockers and the beta-blockers are generally effective in reducing the number of attacks of angina of effort, and most have durations of 4-8 hours. Oral and transdermal nitrates have similar or longer durations. Amyl nitrite, the sublingual nitrates, and esmolol (an IV beta blocker) have short durations of action and are of no value in prophylaxis. The answer is (B).

(A) Block of exercise-induced tachycardia The antianginal effect of propranolol may be attributed to which one of the following? (A) Block of exercise-induced tachycardia (B) Decreased end-diastolic ventricular volume (C) Dilation of constricted coronary vessels (D) Increased cardiac force (E) Increased resting heart rate Propranolol blocks tachycardia but has none of the other effects listed. The answer is (A).

The major common determinant of myocardial oxygen consumption is (A) Blood volume (B) Cardiac output (C) Diastolic blood pressure (D) Heart rate (E) Myocardial fiber tension The answer is (E), fiber tension. The other variables contribute to this determinant.

(B) impaired sexual function (C) Lupus erythematosus syndrome You are considering therapeutic options for a new patient who presents with severe hypertension and angina. In considering adverse effects, you note that an adverse effect which nitroglycerin, guanethidine, and ganglion blockers have in common is (A) Bradycardia (B) impaired sexual function (C) Lupus erythematosus syndrome (D) Orthostatic hypotension (E) Throbbing headache These drugs all reduce venous return sufficiently to cause some degree of postural hypotension (not very prolonged in the case of nitroglycerin). Throbbing headache is a problem only with the nitrates, bradycardia only with guanethidine, sexual problems only with sympathoplegics (ganglion blockers and guanethidine), and lupus with none of them. The answer is (D).

(A) A high incidence of methemoglobinemia on the job Epidemiologic surveys suggest that, in the past, workers exposed to high levels of organic nitrates in the workplace had (A) A high incidence of methemoglobinemia on the job (B) An increased incidence of angina at work as compared with at home (C) A high incidence of cyanide poisoning in the workplace (D) An increased incidence of headaches on Mondays as compared with other days (E) All of the above Nitrites, not nitrates, cause methemoglobinemia in adults. Headache, not angina, increased upon returning to work on Monday. Neither nitrates nor nitrites are related to causation of cyanide poisoning, but nitrites are used as one part of the antidote for cyanide intoxication. The answer is (D).

(C) Isosorbide dinitrate (D) Propranolol (E) Verapamil A patient is admitted to the emergency department following a drug overdose. He is noted to have severe tachycardia. He has been receiving therapy for hypertension and angina. A drug that often causes tachycardia is (A) Diltiazem (B) Guanethidine (C) Isosorbide dinitrate (D) Propranolol (E) Verapamil Isosorbide dinitrate (like all the nitrates) causes reflex tachycardia, but all the other drugs listed here slow heart rate. The answer is (C).

A patient being treated for another condition complains that whenever he takes that medication, his angina becomes worse. Drugs that may precipitate angina when used for other indications include all of the following EXCEPT (A) Amphetamine (B) Hydralazine (C) lsoproterenol (D) Reserpine (E) Terbutaline In general, drugs that cause hypertension or tachycardia--whether directly or by reflex--tend to precipitate angina in individuals with coronary obstruction unless cardiac work is greatly reduced (as in the case of the nitrates). The answer is (D).

(A) Beta-blockers and nitrates on end-diastolic cardiac size When nitrates are used in combination with other drugs for the treatment of angina, which of the following result in additive effects on the variable specified? (A) Beta-blockers and nitrates on end-diastolic cardiac size (B) Beta-blockers and nitrates on heart rate (C) Calcium channel blockers and beta-blockers on cardiac force (D) Calcium channel blockers and nitrates on cardiac force (E) Calcium channel blockers and nitrates on cardiac rate The effects of beta-blockers (or calcium channel blockers) and nitrates on heart size, force, and rate are opposite. The answer is (C).

(C) Isosorbide mononitrate (D) Nifedipine (E) Nimodipine Which of the following is approved for the treatment of hemorrhagic stroke? (A) Amyl nitrite (B) Hydralazine (C) Isosorbide mononitrate (D) Nifedipine (E) Nimodipine (F) Nitroglycerin (sublingual) (G) Nitroglycerin (transdermal) (H) Propranolol (I) Terbutaline (J) Verapamil Nimodipine, a dihydropyridine calcium channel blocker, is approved only for the treatment of hemorrhagic stroke. The answer is (E).

(C) [sosorbide mononitrate (D) Nifedipine (E) Nimodipine Which of the following drugs used for the treatment of angina by inhalation has a very rapid onset and a brief duration of effect (2-5 minutes)? (A) Amyl nitrite (B) Hydralazine (C) [sosorbide mononitrate (D) Nifedipine (E) Nimodipine (F) Nitroglycerin (sublingual) (G) Nitroglycerin (transdermal) (H) Propranolol (I) Terbutaline (J) Verapamil Amyl nitrite, a very volatile liquid, is the only antianginal drug in this list that is usually used by the inhalation route. (Terbutaline is used by aerosol, but it has a longer duration of action and causes angina in susceptible patients.) The answer is (A).

(C) Isosorbide mononitrate (D) Nifedipine (E) Nimodipine Which of the following drugs is capable of maintaining blood levels for 24 hours but with useful therapeutic effects lasting only about 10 hours? (A) Amyl nitrite (B) Hydralazine (C) Isosorbide mononitrate (D) Nifedipine (E) Nimodipine (F) Nitroglycerin (sublingual) (G) Nitroglycerin (transdermal) (H) Propranolol (I) Terbutaline (J) Verapamil Transdermal formulations of nitroglycerin are capable of maintaining blood concentrations for up to 24 hours. Unfortunately, tolerance develops after about 10 hours of continued exposure, so the beneficial effect is limited to about 8-10 hours. The answer is (G).

(C) Isosorbide mononitrate (D) Nifedipine (E) Nimodipine Which of the following is a vasodilator drug used for hypertension that lacks a direct effect on autonomic receptors but may provoke anginal attacks? (A) Amyl nitrite (B) Hydralazine (C) Isosorbide mononitrate (D) Nifedipine (E) Nimodipine (F) Nitroglycerin (sublingual) (G) Nitroglycerin (transdermal) (H) Propranolol (I) Terbutaline (J) Verapamil Hydralazine, a direct-acting vasodilator, often precipitates angina in susceptible individuals; the drug should never be used in patients with coronary disease unless heart rate is appropriately controlled. The answer is (B).

(A) "coronary steal" occurred Your patient has been experiencing chest pain on exertion. One of his friends told him that he has been taking a drug for hypertension and that it is very effective in lowering blood pressure. The friend suggests that your patient try some of the drug: "It won't hurt anything and it may save the expense of a doctor's visit." He tries the agent and experiences severe chest pain, worse than before. The explanation of this phenomenon may be (A) "coronary steal" occurred (B) a nitrate arteriolar dilator should have been used (C) reflex vasoconstriction occurred (D) the drug suppressed the heart (E) venous dilation occurred (Answer:A) If an antihypertensive agent that is an effective arteriolar dilator is used, it is possible to shift blood away from a partially occluded vessel that is adequately perfusing the surrounding tissue when resistance is maintained. Lowering resistance in an adjacent vessel defers blood from the poorly perfused area and intensifies the angina.

(A) a bladder or urethral irritant (Spanish fly) Erectile dysfunction has been treated by numerous agents over the centuries. The effectiveness of these agents depends on intact parasympathetic innervation and (A) a bladder or urethral irritant (Spanish fly) (B) a reduction in the levels of cyclic guanosine monophosphate (cGMP) (C) an alpha2 antagonist to relax nonvascular smooth muscle in the penis (D) an inhibitor of phosphodiesterase isoform 5 (E) blockade of prostaglandin El (PGEl) (Answer:D) Sildenafil, an inhibitor of phosphodiesterase isoform 5, causes the accumulation of cGMP and the generation of nitric oxide and allows blood to enter the penis, resulting in erection. Other than the use of PGEl' analogs have not proven effective in clinical trials

A 49-year-old man is suffering from hypertension, and he has a history of atrial tachycardia. In selecting a calcium channel blocker to manage the tachycardia, the most appropriate agent would be (A) amlodipine (B) isradipine (C) nifedipine (D) propranolol (E) verapamil (Answer:E) Due to the fact that it is more selective for the heart, the most appropriate agent would be verapamil.

(C) production of an increase in myocardial oxygen demand A 55-year-old woman presents with angina pectoris and she is placed on a beta-adrenergic blocking agent. The rationale for the use of a beta blocker is (A) that an increase in end-diastolic volume will increase contractile force development (B) production of a decrease in heart rate, blood pressure, and contractility (C) production of an increase in myocardial oxygen demand (D) production of coronary artery vasodilation (E) redistribution of coronary blood flow to ischemic areas (Answer:B) While redistribution of blood flow may occur, the objective is to decrease oxygen demand. Reducing heart rate, blood pressure, and contractile force development is a major effect of beta blockers and will definitely lead to a decrease in oxygen demand. Beta-adrenergic blocking agents are not vasodilators.

(A) add metoprolol to the regimen (B) add nifedipine to the regimen A 46-year-old man who is overweight and in a high-pressure executive position has been treated with a beta-adrenergic blocking agent (propranolol) for episodes of angina pectoris. The diagnosis is angina of effort. Lately, the effectiveness of propranolol has been less than desired, and he is also complaining that he feels tired. The most appropriate approach to therapy would be to (A) add metoprolol to the regimen (B) add nifedipine to the regimen (C) advise him to quit his job and find another profession (D) increase the dose of propranolol (E) revise the therapy to combine a beta blocker, a calcium channel blocker, and a nitrate (Answer:B) The most effective approach would be to add another class of agents-in this case, calcium channel blocker, or if the choice were given, a nitrate could be selected. Increasing the propranolol will probably increase the feeling of being tired, and another drug from the same class, metoprolol, may not be any more effective. Adding two additional classes of agents is premature. Changing his profession might be a suggestion, but it will probably not be acceptable to him.