1. Chapter 24 Lilley Heart Failure Drugs

2. Conduction System of the Heart 2

3. Class I Class II Class III Class IV The New York Heart Association Classification of HF COPYRIGHT © 2014 BY MOSBY, AN IMPRINT OF ELSEVIER INC. 3

4. Positive inotropic drugs Increase the force of myocardial contraction Positive chronotropic drugs Increase heart rate Positive dromotropic drugs Accelerate cardiac conduction Drug Therapy for Heart Failure 4

5. ACE inhibitors Angiotensin II receptor blockers Beta blockers Aldosterone antagonists B-type natriuretic peptides Phosphodiesterase inhibitors Cardiac glycosides Drug Therapy for Heart Failure (cont’d) 5

6. Prevent sodium and water resorption by inhibiting aldosterone secretion Diuresis results, which decreases preload, or the left ventricular end-volume, and the work of the heart Examples: lisinopril, enalapril, fosinopril, quinapril, captopril, ramipril, trandolapril, and perindopril ACE Inhibitors 6

7. Potent vasodilators; decrease systemic vascular resistance (afterload) Examples: valsartan (Diovan), candesartan (Atacand), eprosartan (Teveten), irbesartan (Avapro), telmisartan (Micardis), olmesartan (Benicar), and losartan (Cozaar) All ARBs are similar in action Angiotensin II Receptor Blockers (ARBs) 7

8. Beta blockers work by reducing or blocking sympathetic nervous system stimulation to the heart and the heart’s conduction system Reduced heart rate, delayed AV node conduction, reduced myocardial contractility, and decreased myocardial automaticity result Examples: metoprolol, carvedilol (Coreg) Beta Blockers 8

9. spironolactone (Aldactone) Potassium-sparing diuretic Also acts as an aldosterone antagonist, which has been shown to reduce the symptoms of heart failure eplerenone (Inspra) Selective aldosterone blocker Aldosterone Antagonist 9

10. hydralazine/isosorbide dinitrate (BiDil) First drug approved for a specific ethnic group, namely African Americans dobutamine Beta 1 -selective vasoactive adrenergic drug Structurally similar to dopamine Miscellaneous Drugs to Treat Heart Failure 10

11. nesiritide (Natrecor) Used in the intensive care setting as a final effort to treat severe, life-threatening heart failure, often in combination with several other cardiostimulatory medications B-type Natriuretic Peptides 11

12. Effects include diuresis (urinary fluid loss), natriuresis (urinary sodium loss), and vasodilation Vasodilating effects on both arteries and veins Indirectly increases cardiac output Suppresses renin-angiotensin system B-type Natriuretic Peptides: Mechanism of Action 12

13. Classroom Response Question Which patient is the best candidate to receive nesiritide therapy? A.A patient with atrial fibrillation who has not responded to other drugs B.A patient needing initial treatment for heart failure C.A patient with reduced cardiac output D.A patient with acutely decompensated heart failure who has dyspnea at rest 13

14. Hypotension Dysrhythmia Headache Abdominal pain B-type Natriuretic Peptides: Adverse Effects 14

15. Work by inhibiting the enzyme phosphodiesterase Results in: Positive inotropic response Vasodilation milrinone (Primacor) Phosphodiesterase Inhibitors 15

16. Short-term management of heart failure Given when patient does not respond to treatment with digoxin, diuretics, and/or vasodilators AHA and ACC advise against long-term infusions Phosphodiesterase Inhibitors: Indications 16

17. milrinone Dysrhythmia Hypotension Angina (chest pain) Hypokalemia Tremor Thrombocytopenia Phosphodiesterase Inhibitors: Adverse Effects 17

18. No longer used as first-line treatment Originally obtained from Digitalis plant, foxglove Digoxin is the prototype Used in heart failure and to control ventricular response to atrial fibrillation or flutter Cardiac Glycosides 18

19. Increase myocardial contractility Change electrical conduction properties of the heart Decrease rate of electrical conduction Prolong the refractory period Area between SA node and AV node Cardiac Glycosides: Mechanism of Action 19

20. Positive inotropic effect Increased force and velocity of myocardial contraction (without an increase in oxygen consumption) Negative chronotropic effect Reduced heart rate Negative dromotropic effect Decreased automaticity at SA node, decreased AV nodal conduction, and other effects Cardiac Glycosides: Drug Effects 20

21. Digoxin Effects The probable mechanism of action for the inotropic effect of digitalis is inhibition of the membrane-bound Na + /K + -ATPase pump; when this occurs, Na + increases in the cell, the exchange of Na + for Ca 2+ is augmented, and calcium influx is increased. The increased intracellular calcium in turn leads to increased release of Ca 2+ from the sarcoplasmic reticulum and increased contractility of the cardiac muscle. Digitalis also has a negative chronotropic effect due to decreased conduction velocity in the atrioventricular (AV) node 21

22. Increased stroke volume Reduction in heart size during diastole Decrease in venous BP and vein engorgement Increase in coronary circulation Promotion of diuresis because of improved blood circulation Palliation of exertional and paroxysmal nocturnal dyspnea, cough, and cyanosis Cardiac Glycosides: Drug Effects (cont’d) 22

23. Heart failure Supraventricular dysrhythmias Atrial fibrillation and atrial flutter Cardiac Glycosides: Indications 23

24. Classroom Response Question A patient is in the emergency department with new onset atrial fibrillation. Which order for digoxin would most likely have the fastest therapeutic effect? A. Digoxin 0.25 mg PO daily B. Digoxin 1 mg PO now, then 0.25 mg PO daily C. Digoxin 0.5 mg IV push daily D. Digoxin 1 mg IV push now, then 0.25 mg IV daily 24

25. Digoxin (Lanoxin) Very narrow therapeutic window Drug levels must be monitored 0.5 to 2 ng/mL Low potassium levels increase its toxicity Electrolyte levels must be monitored Cardiovascular Dysrhythmias, including bradycardia or tachycardia CNS Headaches, fatigue, malaise, confusion, convulsions Eye Colored vision (seeing green, yellow, purple), halo vision, flickering lights GI Anorexia, nausea, vomiting, diarrhea Cardiac Glycosides: Adverse Effects 25

26. For hyperkalemia <5 mEq/L, use insulin plus glucose, and sodium bicarbonate if the patient is acidotic Treatment with digoxin Fab fragments is indicated for a K + level greater than 5 mEq/L Hemodialysis may be necessary for uncontrolled hyperkalemia Correct hypokalemia (usually in chronic intoxication) Concomitant hypomagnesemia may result in refractory hypokalemia Digoxin Toxicity 26

27. Digibind Therapy Continued for Digoxin Toxicity Toxicity During Chronic Therapy Acute distress or for whom a serum digoxin concentration is not available: Administer 6 vials Renal Impairment Dose adjustment not necessary but use caution as digoxin immune Fab complex is renally eliminated Administration Administer by IV infusion over 15-30 minutes (see IV information) May be given IVP for life-threatening dysrhythmias Other Indications & Uses For life-threatening dysrhythmias or hypotension unresponsive to other measures caused by digoxin, digitoxin or related toxins (ie, foxglove) [K+] >5 mEq/L in setting of severe digoxin intoxication, especially if increased creatinine 27

28. Digibind Adverse Effects? Med Adverse Effects Effects (due to ?) include exacerbation of HF, rapid ventricular response in patients with a.fib; postural hypotension 28

29. Classroom Response Question A patient is receiving digoxin 0.25 mg daily as part of treatment for heart failure. The nurse assesses the patient before medication administration. Which assessment finding would be of most concern? A. Apical heart rate of 58 beats/min B. Blood Pressure 130/70 C. Serum potassium level of 2.9 mEq/L D. Serum digoxin level of 0.8 ng/mL 29

30. Assess history, drug allergies, contraindications Assess clinical parameters, including: BP Apical pulse for 1 full minute Heart sounds, breath sounds For apical pulse less than 60 or greater than 100 beats/min Hold dose Notify prescriber Heart Failure Drugs: Nursing Implications 30

31. Assess clinical parameters (cont’d) Weight, I&O measures ECG Serum labs: potassium, sodium, magnesium, calcium, renal, and liver function studies Heart Failure Drugs: Nursing Implications (cont’d) 31

32. Hold dose and notify prescriber if patient experiences signs/symptoms of toxicity Anorexia, nausea, vomiting, diarrhea Visual disturbances (blurred vision, seeing ?) Heart Failure Drugs: Nursing Implications (cont’d) 32

33. Xanthopsia Ocular manifestations include xanthopsia (seeing yellow). Most experts believe that the famous artist Vincent van Gogh was using foxglove (the flower that digoxin is derived from) and this explains his yellow paintings toward the end of his life. See two of the paintings below:xanthopsia 33

34. Van Gogh –yellow tint to paintings, also painted halos COPYRIGHT © 2014 BY MOSBY, AN IMPRINT OF ELSEVIER INC. 34

35. Check dosage forms carefully, and follow instructions for administering Avoid giving digoxin with high-fiber foods (fiber binds with digitalis) Patients should immediately report a weight gain of 2 lb or more in 1 day or 5 lb or more in 1 week Heart Failure Drugs: Nursing Implications (cont’d) 35

36. Nesiritide or milrinone Use an infusion pump Monitor I&O, heart rate and rhythm, BP, daily weights, respirations, and so on Heart Failure Drugs: Nursing Implications (cont’d) 36

37. Monitor for therapeutic effects Increased urinary output Decreased edema, shortness of breath, dyspnea, crackles, fatigue Resolution of paroxysmal nocturnal dyspnea Improved peripheral pulses, skin color, temperature Monitor for adverse effects Heart Failure Drugs: Nursing Implications (cont’d) 37

38. A patient with a history of heart failure presents to the emergency department with difficulty breathing, cough, and edema of the lower extremities. The nurse anticipates administration of which type of medication? A.Negative chronotrope B.Positive inotrope C.Negative inotrope D. Diuretic Case Study 38

39. The patient is prescribed an ACE inhibitor. The nurse understands the primary mechanism by which the ACE inhibitors exert their therapeutic effect in a patient in heart failure is: A.to inhibit catecholamine release. B.to inhibit acetylcholine release. C.to inhibit aldosterone secretion. D.to prevent vagal stimulation. Case Study (cont’d) 39

40. The patient is discharged home and returns to the emergency department 4 days later. The patient is admitted to the intensive care unit with acute decompensated heart failure with dyspnea at rest. The nurse anticipates administration of which medication? A.atropine B.carvedilol (Coreg) C.lisinopril (Prinivil) D.nesiritide (Natrecor) Case Study (cont’d) 40