Cardiovascular Pharmacology Practice Quiz

1. CardiovascularPharmacologyPractice Quiz HUCM Class of 2006 Unit III Exam I Prep

2. Question #1Angiotensin – converting enzyme inhibitors such as enalapril also act to increase the activity of which of the following substances? • Vasopressin • Endothelins • Brandykinin • Substance P • Enkephalins HUCM Class of 2006

3. Question #1Angiotensin – converting enzyme inhibitors such as enalapril also act to increase the activity of which of the following substances? • Brandykinin • ACE inhibitors not only inhibit the formation of a vasoconstrictor, angiotensin II, they also inhibit the degradation of a vasodilator, bradykinin. This latter effect results from inhibition of the kinases that inactive bradykinin. Other peptides that cause vasodilation include substance P and atrial natriuretic peptide. Endothelins and vasopressin cause vasoconstriction. HUCM Class of 2006

4. Question #2Nifedipine and verapril share which of the following physiologic effects? • Decrease systemic vascular resistance • Decrease heart rate • Block vascular and cardiac calcium channels equally • Selectively block cardiac calcium channels • Selectively block calcium channels in smooth muscle HUCM Class of 2006

5. Question #2Nifedipine and verapril share which of the following physiologic effects? • Decrease systemic vascular resistance • Verapamil has approximately equal effects on calcium channels in smooth muscle and cardiac tissue, whereas nifedipine and other dihydropyridines selectively block calcium channels in smooth muscle. Both agents can lower vascular resistance, but only verapamil decreases heart rate. Nifedipine may cause reflex tachycardia. HUCM Class of 2006

6. Question #3Both propranolol and hydrochlorothiazide: • Decrease blood volume and peripheral resistance • Decrease heart rate • Can adversely affect serum lipids • Can cause hypokalemia • Elevate plasma renin activity HUCM Class of 2006

7. Question#3Both propranolol and hydrochlorothiazide: • Can adversely affect serum lipids • Both propanolol and hydrochlorothiazide can have adverse effects on serum lipids. Beta – blockers can elevate triglycerides and decrease HDL cholesterol, whereas diuretics increase LDL in some patients. • Only diuretics can decrease serum potassium and cause hypokalemia. In addition, diuretics decrease blood volume and peripheral resistance whereas renin activity usually increases secondary to blood volume contraction. Only B – blockers decrease heart rate. HUCM Class of 2006

8. Question #4All of the following antihypertensive agents decrease peripheral vascular resistance EXCEPT: • Propranolol • Terazosin • Nifedipine • Hydralazine • Methyldopa HUCM Class of 2006

9. Question #4All of the following antihypertensive agents decrease peripheral vascular resistance EXCEPT: • Propranolol • B – Adrenoreceptors antagonists such as propanolol do not lower peripheral resistance and may even increase it either by blocking vascular B2 – receptors or by a reflex mechanism that follows the initial reduction in blood pressure. • Alpha – adrenoreceptor antagonists such as terazosin, calcium channel blockers such as nifedipine, direct – acting vasodilators such as hydralazine, and centrally acting sympatholytics such as methyldopa act to decrease vascular resistance. HUCM Class of 2006

10. Propranolol Clonidine Prazosin Captopril Minoxidil First – dose syncope Severe bronchoconstriction in asthmatic patient Renal failure in patients with bilateral renal artery stenosis Sedation and dry mouth Hypertrichosis, particularly in women Question #5Select the antihypertensive drug that is most likely to cause each adverse effect HUCM Class of 2006

11. Propranolol – Severe bronchoconstriction in asthmatic patient Clonidine – Sedation and dry mouth Prazosin – First Dose Syncope Captopril – Renal failure in patients with bilateral renal artery stenosis Minoxidil - Hypertrichosis Question #5Select the antihypertensive drug that is most likely to cause each adverse effect HUCM Class of 2006

12. Question#6 Match each cardiovascular drug with its effect: • Verapamil • Propranolol • Hydralazine • Nitroglycerine (sublingual) HUCM Class of 2006

13. Question#6 Match each cardiovascular drug with its effect: • Verapamil - C • Propranolol - A • Hydralazine - D • Nitroglycerine (sublingual) - B HUCM Class of 2006

14. Question #6 Explained • Propanolol decreases heart rate and myocardial contractility, thereby decreasing myocardial oxygen consumption. Propanolol can increase ventricular filling pressure and preload slightly, but does not significantly decrease peripheral resistance. • Verapamil inhibits calcium channels in vascular smooth muscle and cardiac muscle and decreases peripheral vascular resistance and heart rate, thereby decreasing myocardial oxygen requirement. Verapamil has relatively little effect on venous smooth muscle and ventricular filling pressure. • Hydralazine relaxes arteriolar smooth muscle and markedly reduces peripheral vascular resistance. This drug can cause a significant reflex tachycardia and thereby increase oxygen consumption. • Nitroglycerin is primarily a venodilator when given sublingually: it decreases ventricular filling pressure and cardiac oxygen consumption, but can cause reflex tachycardia. HUCM Class of 2006

15. Practice Clinical Vignettes HUCM Class of 2006

16. Case #1A 48 year old type 2 diabetic patient presents with complaints of polyuria and polydipsia. Laboratory evaluation reveals a blood glucose of 192 mg/dL. She states that her diabetes had been well controlled and that she had been symptom – free for the past 8 years. Recently, however, she began taking medication for hypertension. Which of the following antihypertensive drugs is she most likely taking? • Diltazem • Enalapril • Hydrochlorothiazide • Methyldopa • Terazosin HUCM Class of 2006

17. Case #1A 48 year old type 2 diabetic patient presents with complaints of polyuria and polydipsia. Laboratory evaluation reveals a blood glucose of 192 mg/dL. She states that her diabetes had been well controlled and that she had been symptom – free for the past 8 years. Recently, however, she began taking medication for hypertension. Which of the following antihypertensive drugs is she most likely taking? • Hydrochlorothiazide • The fact that the patient had well – controlled diabetes until the addition of an antihypertensive medication suggests that the new agent is responsible. Hydrochlorothiazide is a thiazide diuretic that is know to increase fasting blood glucose in diabetic patients. HUCM Class of 2006

18. Case #2A 33 – year – old with a history of asthma is being treated for symptoms of hyperthyroidism. Which of the following beta – blockers would be an appropriate therapy for this patient? • Isoproterenol • Labetalol • Metoprolol • Propranolol • Timolol HUCM Class of 2006

19. Case #2A 33 – year – old with a history of asthma is being treated for symptoms of hyperthyroidism. Which of the following beta – blockers would be an appropriate therapy for this patient? • Metoprolol • Symptoms related to hyperthyroidism include palpitations and tachycardia. If the patient is also asthma, you should select a drug that blocks beta1 – receptors without affecting the beta2 – receptors found in the respiratory smooth muscle. Therefore, a selective beta1 – blocker (such as metaprolol) would be appropriate. HUCM Class of 2006

20. Case #2: Answer Explanations Continued • Isoproterenol is a non – selective beta agonist, not antagonist • Labetalol is a mixed alpha and nonselective beta antagonist used for chronic hypertension and hypertensive emergencies • Propanolol is a nonselective beta antagonist. It would block both beta1 and beta2 receptors and would therefore be contraindicated in a patient with asthma. • Timolol is also a nonselective beta – antagonist that is used topically in the treatment of glaucoma. HUCM Class of 2006

21. Case #3A patient with essential hypertension is starting diuretic therapy. He has a history of calcium oxalate renal stones. Which of the following diuretics would be most appropriate for this patient? • Acetazolamide • Furosemide • Hydrochlorothiazide • Spironolactone • Triamterene HUCM Class of 2006

22. Case #3A patient with essential hypertension is starting diuretic therapy. He has a history of calcium oxalate renal stones. Which of the following diuretics would be most appropriate for this patient? • Hydrochlorothiazide • A thiazide diuretic would be the drug of choice for this patient because it is the only class of diuretic that decrease urinary secretion of calcium. Thiazide diuretics, like hydrochlorothaizide, inhibit the Na+/Cl- cotransporter in the distal convoluted tubule and promote the reabsorption of calcium. HUCM Class of 2006

23. Case#3 Explanations Continued • Acetazolamide, a carbonic anhydrase inhibitor, and furosemide, a loop diuretic, induce diuresis at the expense of all three major cationic electrolytes ( Na+, K+, Ca2+), which are secreted in increased amounts. • Spironolactone and triamterene so – called potassium – sparing diuretics block Na+/K+ exchanges in the collecting duct. Although they decrease K+ secretion, they elevate Na+ and Ca2+ secretion. HUCM Class of 2006

24. Case #4A 68 – year old man presents with complaints of chronic fatigue, exertional and nocturnal dyspnea, orthopnea, and a chronic nonproductive cough. On examination, respiratory wheezing and rhonchi are noted. Cardiac examination reveals a diminished first heart sound and an S3 gallop. The patient indicates that he was recently treated for hypertension and vasospastic angina. On the basis of his initial presentation, which of the following agents was most likely prescribed. • Amlodipine • Captopril • Furosemide • Hydralazine • Verapril HUCM Class of 2006

25. Case #4A 68 – year old man presents with complaints of chronic fatigue, exertional and nocturnal dyspnea, orthopnea, and a chronic nonproductive cough. On examination, respiratory wheezing and rhonchi are noted. Cardiac examination reveals a diminished first heart sound and an S3 gallop. The patient indicates that he was recently treated for hypertension and vasospastic angina. On the basis of his initial presentation, which of the following agents was most likely prescribed. • Verapamil • This patient is presenting with classic signs and symptoms of congestive heart failure (highlighted above). Verapamil is a calcium channel blocker used to treat both HTN and vasospastic angina. However, it has a strong inotropic effect on the heart that can cause signs and symptoms of heart failure. Furthermore, some clinical studies have shown that congestive heart failure can develop in a small percentage of individuals taking verapamil HUCM Class of 2006

26. Case#4 Explanation Continued • Amlodipine is also a calcium channel blocker used in the treatment of both HTN and vasospastic angina. However it does not have negative inotropic effect on the heart and does not cause signs and symptoms of heart failure. Furthermore, amlodipine is generally well tolerated in heart failure patients. • Captopril is an ACE inhibitor used in the treatment of both HTN and CHF. Therefore, this agent would not show signs and symptoms of CHF. • Furosemide is a diuretic commonly used to treat the congestion and edema associated with heart failure. It can also be used to treat HTN. • Hydralazine is a vasodilator used primarily to treat signs and symptoms associated with heart failure. The use of this agent in patients with angina is not recommended because it can potentiate angina. HUCM Class of 2006

27. Case #5A 59 – year old man with a history of MI presents to his physician complaining of shortness of breath. On examination, his heart rate is 110/min and respiratory rate is 22/min. He has rales in both long fields, a normal sinus rhythm with an S3 gallop, and a 2+ pitting ankle edema. A chest x – ray film reveals cardiomegaly, and his ejection fraction on echocardiogram is calculated at 37%. Which of the following medication would alleviate this patient’s symptoms by significantly reducing both the preload and afterload on the heart without affecting its inotropic state. • Digoxin • Diltiazem • Enalapril • Furosemide • Propanolol HUCM Class of 2006

28. Case #5A 59 – year old man with a history of MI presents to his physician complaining of shortness of breath. On examination, his heart rate is 110/min and respiratory rate is 22/min. He has rales in both long fields, a normal sinus rhythm with an S3 gallop, and a 2+ pitting ankle edema. A chest x – ray film reveals cardiomegaly, and his ejection fraction on echocardiogram is calculated at 37%. Which of the following medication would alleviate this patient’s symptoms by significantly reducing both the preload and afterload on the heart without affecting its inotropic state. • Enalapril • Everything in this case points to congestive heart failure (highlighted above). A drug that will alleviate the symptoms by decreasing both preload and afterload is necessary. • Enalapril is an ACE inhibitor. ACE inhibitors work by blocking the conversion of angiotensin I to angiotensin II in the lungs. Angiotensin II is both a potent vasoconstrictor and a stimulator of aldosterone production. Aldosterone acts by promoting sodium (and thus water) reabsorption by the kidney. An Ace inhibitor will therefore promote vasodilation (reducing afterload) as well as reduce intravascular volume (decreasing preload). It does not affect the heart’s inotropic state. HUCM Class of 2006

29. Case #5 Explanation Continued • Although digoxin is a mainstay in the therapy of CHF, it has no effect on either preload or afterload. Instead, it works by having a positive inotropic effect on the heart. The mechanism involves inhibition of Na+/K+ ATPase and consequent increase in intracellular calcium, which in turn, increases the heart’s contractile force. • Diltiazem is a calcium channel blocker. As their name implies, calcium channel blockers block the influx of calcium (via specific calcium channels) into the cell from the ECF; this interferes with excitation – contraction coupling in cardiac muscle, producing a negative inotropic effect. Although these drugs can be used in the treatment of hypertension and angina (they inhibit the contraction of smooth muscle and thereby decrease peripheral vascular resistance / afterload), they are contraindicated in patients with CHF because of their negative inotropic effects • Furosemide is a loop diuretic. It decreases intravascular volume (and hence preload), but at typical doses has no significant effect on either afterload of inotropic state. Diuretics are often used in the treatment of CHF, and furosemide is used for the immediate relief of pulmonary congestion. • Propanolol is a beta – blocker. It has negative inotropic effect on the heart and is therefore contraindicated in patients with CHF HUCM Class of 2006

30. Case #6A patient who is being treated for a myocardial infarction that occurred 2 hours ago is medicated with IV nitroprusside. Which of the following is the expected action of this drug? • Constriction of the arterioles alone • Constriction of both arterioles and venules • Constriction of venules alone • Dilatation of arterioles alone • Dilatation of arterioles and venules HUCM Class of 2006

31. Case #6A patient who is being treated for a MI that occurred 2 hours ago is medicated with IV nitroprusside. Which of the following is the expected action of this drug? • Dilatation of arterioles and venules • Nitroprusside is somewhat tricky to use, but is a very useful IV agent that causes dilatation of both arterioles and venules. It has a very rapid onset of action and is typically used in an emergency department or ICU situation. The typical setting is a patient with acute or chronic low cardiac output and high ventricular filling pressure due to poor systolic left ventricular function. Underlying causes for the poor ventricular function may be diverse: dilated cardiomyopathy (DCM), acute MI, chronic coronary heart disease, or aortic or mitral incompetence, Nitroprusside can improve perfusion of vital organs and reduce the workload of the heart. HUCM Class of 2006

32. Case#6 Explanation Continued • Problems sometimes encountered with this drug include hypotension (best avoided by starting with a low dose and continuously monitoring systemic arterial and pulmonary capillary wedge pressures) and accumulation of toxic metabolites of cyanide in patients with liver or renal failure. Many physicians prefer to use IV nitrate rather than nitroprusside because of its lesser toxicity. HUCM Class of 2006

33. References • Kaplan USMLE Step 1 QBook (2001) • Board Simulator Series Body Systems Review I: Hematopoietic / Lymphoreticular, Respiratory, Cardiovascular 2nd Edition (1997) HUCM Class of 2006

34. Happy Studying ! Another Philippians 4:13 Production