Agents for Treating Heart Failure PDF

Chapter 44 Agents for Treating Heart Failure Copyright Copyright © 2017 © 2012 Wolters Wolters Kluwer Kluwer All Health Rights Reserved...

Chapter 44 Agents for Treating Heart Failure Copyright Copyright © 2017 © 2012 Wolters Wolters Kluwer Kluwer All Health Rights Reserved | Lippincott Williams & Wilkins Heart Failure #1  Condition in which the heart fails to effectively pump blood throughout the body  Due to structural and/or functional irregularities in the heart, there is low cardiac output  Four stages o Stage A: High risk for HF but no structural heart disease or symptoms o Stage B: Structural heart disease but no signs or symptoms of HF o Stage C: Structural heart disease with prior or current symptoms of HF o Stage D: Refractory HF requiring specialized interventions Copyright © 2023 Wolters Kluwer All Rights Reserved Heart Failure #2 Functional classifications o Class I: No limitation of physical activity o Class II: Slight limitation of physical activity o Class III: Marked limitation of physical activity o Class IV: Unable to perform any physical activity without symptoms, or symptoms at rest Usually involves dysfunction of cardiac muscle Copyright © 2023 Wolters Kluwer All Rights Reserved The Sliding Filaments of Myocardial Muscles Copyright © 2023 Wolters Kluwer All Rights Reserved Some Common Disorders That Lead to Heart Failure Coronary artery disease Cardiomyopathy Hypertension Valvular heart disease Copyright © 2023 Wolters Kluwer All Rights Reserved Compensatory Mechanisms Decreased cardiac output stimulates: o Sympathetic stimulation o Positive inotropic effect o Release of renin Over time, compensation mechanisms increase heart’s workload o Muscle stretches and/or thickens o Chambers are not able to effectively pump blood o Leads to increased HF Copyright © 2023 Wolters Kluwer All Rights Reserved Compensatory Mechanisms in HF Copyright © 2023 Wolters Kluwer All Rights Reserved Signs and Symptoms of Heart Failure Copyright © 2023 Wolters Kluwer All Rights Reserved Treatment Algorithm Copyright © 2023 Wolters Kluwer All Rights Reserved Use of Agents to Treat Heart Failure Across the Lifespan Copyright © 2023 Wolters Kluwer All Rights Reserved Sites of Actions of Drugs Used to Treat Heart Failure Copyright © 2023 Wolters Kluwer All Rights Reserved Cardiac Glycosides #1 Digoxin (Lanoxin) used to treat HF symptoms Therapeutic actions o Increases intracellular calcium, allows more calcium to enter the myocardial cell during depolarization, causing:  Increased force of myocardial contraction  Increased cardiac output, renal perfusion  Slowed heart rate  Decreased conduction velocity o Overall effect is increased cardiac output Copyright © 2023 Wolters Kluwer All Rights Reserved Cardiac Glycosides #2 Indications o Treatment of HF, atrial flutter, atrial fibrillation, paroxysmal atrial tachycardia Pharmacokinetics o Rapid onset of action o Rapidly absorbed and widely distributed throughout the body o Primarily excreted unchanged in the urine Copyright © 2023 Wolters Kluwer All Rights Reserved Cardiac Glycosides #3  Contraindications o Allergy o Ventricular tachycardia or fibrillation o Heart block or sick sinus syndrome o Idiopathic hypertrophic subaortic stenosis o Acute MI o Renal insufficiency o Electrolyte abnormalities  Cautions o Pregnancy and lactation Copyright © 2023 Wolters Kluwer All Rights Reserved Cardiac Glycosides #4 Adverse effects o Most frequently seen: headache, weakness, drowsiness, and vision changes o GI upset and anorexia o Arrhythmias o Digoxin toxicity Copyright © 2023 Wolters Kluwer All Rights Reserved Cardiac Glycosides #5 Drug–drug interactions o Verapamil, amiodarone, quinidine, quinine, erythromycin, tetracycline, cyclosporine o Potassium-losing diuretics o Thyroid hormones, metoclopramide, penicillamine o Cholestyramine, charcoal, colestipol, antacids, bleomycin, cyclophosphamide, methotrexate Copyright © 2023 Wolters Kluwer All Rights Reserved Cardiac Glycoside Prototype Copyright © 2023 Wolters Kluwer All Rights Reserved Question #1 Please answer the following statement as true or false. The first goal of treatment for heart failure is to make the heart beat harder and faster. Copyright © 2023 Wolters Kluwer All Rights Reserved Answer to Question #1 False Rationale: The first goal of treatment is to decrease the work on the heart. Copyright © 2023 Wolters Kluwer All Rights Reserved Phosphodiesterase Inhibitors #1  Milrinone (generic) is the only drug currently available in this class  Therapeutic actions o Blocks the enzyme phosphodiesterase, leading to increase in cAMP, which increases the calcium level in the cell, causing a stronger contraction and prolonging effects of sympathetic stimulation  Indications o Short-term treatment of HF that has not responded to digoxin or diuretics alone or has poor response to digoxin, diuretics, and vasodilators o Use is limited to severe situations Copyright © 2023 Wolters Kluwer All Rights Reserved Phosphodiesterase Inhibitors #2  Pharmacokinetics o Available only for IV use o Widely distributed after injection o Metabolized in the liver; excreted primarily in the urine  Contraindications o Allergy o Severe aortic or pulmonic disease o Acute MI o Fluid volume deficit o Ventricular arrhythmias  Cautions o Pregnancy and lactation Copyright © 2023 Wolters Kluwer All Rights Reserved Phosphodiesterase Inhibitors #3 Adverse effects o Most frequently seen: arrhythmias, hypotension, chest pain o GI effects o Thrombocytopenia o Hypersensitivity reactions o Burning at IV injection site Copyright © 2023 Wolters Kluwer All Rights Reserved Nursing Considerations for Phosphodiesterase Inhibitors Assess: o History and physical examination o Known allergies, acute aortic or pulmonic valvular disease, acute MI or fluid volume deficit, and ventricular arrhythmias o Pregnancy and lactation o Cardiac status and heart sounds Drug–drug interactions o Furosemide Copyright © 2023 Wolters Kluwer All Rights Reserved Phosphodiesterase Inhibitor Prototype Copyright © 2023 Wolters Kluwer All Rights Reserved Hyperpolarization-Activated Cyclic Nucleotide–Gated Channel Blockers #1  Ivabradine (Corlanor)  Therapeutic actions o Blocks HCNs, which slows the sinus node in the repolarizing phase of the action potential  Leads to reduction in heart rate  Indications o Reduce risk of hospitalization for worsening HF  Pharmacokinetics o Rapidly absorbed through GI tract o Metabolized in the liver and intestines; excreted in the feces and bile Copyright © 2023 Wolters Kluwer All Rights Reserved Hyperpolarization-Activated Cyclic Nucleotide–Gated Channel Blockers #2 Contraindications o Known allergy o Active, decompensated HF o Hypotension o Sick sinus syndrome of AV block o Resting heart rate under 60 beats/min o Dependency on a pacemaker o Severe hepatic impairment Copyright © 2023 Wolters Kluwer All Rights Reserved Hyperpolarization-Activated Cyclic Nucleotide–Gated Channel Blockers #3 Cautions o Atrial fibrillation or moderate heart block o Pregnancy and lactation Adverse effects o Most frequently seen: bradycardia, hypertension, atrial fibrillation, luminous phenomena Drug–drug interactions o Strong CYP3A4 inhibitors or inducers o Other negative chronotropic drugs Copyright © 2023 Wolters Kluwer All Rights Reserved Hyperpolarization-Activated Cyclic Nucleotide–Gated Channel Blocker Prototype Copyright © 2023 Wolters Kluwer All Rights Reserved Angiotensin Receptor Neprilysin Inhibitor #1 Entresto (an ARNI) o Combination of valsartan and sacubitril Therapeutic actions o Blocks breakdown of natriuretic peptides o Inhibits effects of RAAS o Leads to decreased cardiac workload, lower vascular volume, lower blood pressure, improved HF symptoms Copyright © 2023 Wolters Kluwer All Rights Reserved Angiotensin Receptor Neprilysin Inhibitor #2  Indications o Reduce risk of CV death and hospitalization in adults with chronic HF o Treatment of symptomatic HF with systemic left ventricular systolic dysfunction in pediatric patients over 1 year of age  Pharmacokinetics o After oral administration dissociates into sacubitril and valsartan o Highly bound to plasma proteins o Sacubitril metabolized by esterases; valsartan remains mostly unmetabolized o Eliminated in urine and feces Copyright © 2023 Wolters Kluwer All Rights Reserved Angiotensin Receptor Neprilysin Inhibitor #3  Contraindications o Allergy o History of angioedema related to exposure to ACEI or ARB medication o Concurrent use with an ACEI o Concurrent use with aliskiren o Pregnancy and lactation  Adverse effects o Common: hypotension, hyperkalemia, cough, dizziness, renal impairment o Monitor patients for signs of low BP and angioedema Copyright © 2023 Wolters Kluwer All Rights Reserved Angiotensin Receptor Neprilysin Inhibitor #4 Drug–drug interactions o ACEIs o Aliskiren o Potassium-sparing diuretics o Lithium o Other nephrotoxic medications Copyright © 2023 Wolters Kluwer All Rights Reserved Angiotensin Receptor Neprilysin Inhibitor Prototype Copyright © 2023 Wolters Kluwer All Rights Reserved Question #2 The nurse is caring for a patient who has presented to the emergency department with signs and symptoms of acute MI. While making an initial assessment of this patient, the nurse notes that the patient has had adverse reactions to digoxin and a history of heart failure. The physician writes admission orders. Which of the following drugs would be of concern? A. Furosemide (Lasix) B. Milrinone (Primacor) C. Propranolol (Inderal LA) D. Aspirin Copyright © 2023 Wolters Kluwer All Rights Reserved Answer to Question #2 B. Milrinone (Primacor) Rationale: Caution should be taken administering milrinone in the following conditions: severe aortic or pulmonic valvular disease, which could be exacerbated by increased contraction; acute MI, which could be exacerbated by increased oxygen consumption and increased force of contraction; fluid volume deficit, which could be made worse by increased renal perfusion; and ventricular arrhythmias, which could be exacerbated by this drug. Copyright © 2023 Wolters Kluwer All Rights Reserved