Understanding Heart Failure

Heart Failure

• An abnormal condition involving impaired cardiac pumping/filling
• Inability of the heart to produce adequate cardiac output (CO) to meet metabolic needs.
• Characterized by ventricular dysfunction, reduced exercise tolerance, diminished quality of life, and shortened life expectancy.

Etiology and Pathophysiology

• Primary risk factors include CAD and advancing age.
• Contributing risk factors include hypertension, diabetes, tobacco use, obesity, and high serum cholesterol.

Heart Failure: Causes

• Cardiac defects include myocardial infarction and valve deficiency.
• Defects outside the heart include coronary artery disease, pulmonary hypertension, and diabetes, causing stiffened vessels.

Pathophysiology: Systolic Failure

• There is a decrease in the left ventricular ejection fraction (EF).
• Can be caused by impaired contractile function (e.g., MI), inability of heart to pump effectively, hypertension, cardiomyopathy (enlarged Left Ventricle), and mechanical abnormalities (e.g., valve disease)

Pathophysiology: Diastolic Failure

• Impaired ability of the ventricles to relax and fill during diastole, resulting in decreased CO.
• Diagnosed based on the presence of pulmonary congestion, pulmonary hypertension, ventricular hypertrophy, and a normal EF (ejection fraction).
• Caused by left ventricular hypertrophy from chronic hypertension, aortic stenosis, and cardiomyopathy.

Types of Heart Failure: Right Sided

• Signs and Symptoms can be Murmurs, Jugular Venous Distention, Edema, Weight gain, Ascites, Anasarca, Hepatomegaly, Fatigue, Anxiety, Right upper quadrant pain, Anorexia and GI bloating, Nausea.

Types of Heart Failure: Left Sided – Acute Decompensated Heart failure (ADHF)

• Signs and Symptoms can be Pulses alternas, Increased HR, Crackles, S3 and S4, Pleural effusion, Changes in mental status, Restlessness and confusion, Weakness, fatigue, Anxiety, depression, Dyspnea, Shallow respirations, Orthopnea, Dry, hacking cough, Nocturia

Manifestations of Acute Decompensated Heart Failure (ADHF)

• Physical findings include orthopnea, dyspnea/tachypnea (worsening), use of accessory muscles, cool and clammy skin, cough with frothy, blood-tinged sputum (pink), breath sounds (crackles, wheezes, rhonchi), tachycardia, hypotension or hypertension, and cyanosis (late sign).
• Pulmonary edema, often life-threatening; Early signs include an increase in the respiratory rate and a decrease in PaO2; Later signs include tachypnea and respiratory acidosis.

Clinical Manifestations: Chronic HF

• Fatigue, dyspnea, orthopnea, paroxysmal nocturnal dyspnea
• Persistent, dry cough, unrelieved with position change or over-the-counter cough suppressants
• Tachycardia (compensate for lack of 02 & CO2 exchange), low CO
• Restlessness, confusion, decreased memory (poor perfusion to brain)
• Chest pain (angina), weight changes, and is often accompanied by anorexia, nausea, and fluid retention.

Complications: HF

• Pleural effusion (fluid retention in the pleural space).
• Atrial fibrillation (most common dysrhythmia); Promotes thrombus/embolus formation, increasing risk for stroke/PE.
• High risk of fatal dysrhythmias (e.g., sudden cardiac death, ventricular tachycardia)
• HF can lead to severe hepatomegaly, especially with RV failure; Fibrosis and cirrhosis can develop over time.
• Renal insufficiency or failure.

Drug Therapy for Heart Failure

• Includes inotropic drugs (influence the force of myocardial contraction)
• Chronotropic drugs (influence heart rate)
• Dromotropic drugs (influence conduction).
• Used to treat heart muscle failure includes ACE inhibitors, Angiotensin II receptor blockers, Beta blockers, Aldosterone antagonists, B-type natriuretic peptides, Phosphodiesterase inhibitors, Cardiac glycosides, Loop Diuretics, and Miscellaneous.

ACE Inhibitors

• Prevent sodium and water reabsorption by inhibiting aldosterone secretion.
• Results in Diuresis via decreased preload, decreased blood volume, decreased blood return to the heart, and decreased work of the heart.
• Used for Hypertension, Heart Failure, and Acute MI.
• Examples are lisinopril, enalapril, fosinopril, captopril, quinapril, ramipril, trandolapril, perindopril.

Angiotensin II Receptor Blockers ARBS

• Potent vasodilators that decrease systemic vascular resistance (afterload).
• Used with diuretics in the treatment of hypertension or heart failure.
• Examples: valsartan (Diovan), candesartan (Atacand), losartan (Cozaar).
• Side Effects: URI, Hyperkalemia - less likely than ACE inhibitors

Beta Blockers

• Work by reducing or blocking sympathetic nervous system stimulation to the heart and the heart's conduction system and to take pulse at home.
• Side Effects: impotence, mental depression.
• Cautions: The use of Beta Blockers in asthmatic people may cause bronchoconstriction and mask signs of hypoglycemia in people with diabetes

Aldosterone Antagonist

• An aldosterone antagonist used in severe stages that blocks aldosterone and promotes diuresis.
• Spironolactone (Aldactone) is a potassium-sparing diuretic.
• Also acts as an aldosterone antagonist, reducing the symptoms of heart failure.
• Eplerenone (Inspra) is also a Selective aldosterone blocker

B-type Natiuretic Peptides

• Vasodilating effects on arteries and veins, indirectly increases cardiac output, suppresses renin-angiotensin system, producing diuresis
• Used for the Treatment of Life Threatening Heart Failure in ICU therapy by IV infusion that delivers a continuous infusion
• EX: nesiritide (Natrecor)—only drug in class that its severe, life-threatening heart failure
• Adverse Effects of B-type Natiuretic Peptides: Hypotension, dysrhythmia, headache, and abdominal pain

Phosphodiesterase Inhibitors

• Works by inhibiting the enzyme phosphodiesterase and improves squeeze of heart resulting in positive inotropic response and increased force of heart contraction increasing CO through vasodilation allowing Short-term management of heart failure in ICU through Continuous IV infusion such as Milrinone (Primacor) .
• Given when the patient doesn't respond to treatment with digoxin, diuretics, and/or vasodilators.

Cardiac Glycosides

• An Oldest group of drugs such as Digitalis plant, foxglove that decreases in venous system’s BP and vein engorgement allowing Increase in coronary circulation with the aid of diuresis making improved blood flow used to treat heart failure or Supraventricular dysrhythmias including Atrial fibrillation and atrial flutter

Digoxin: Adverse Effects

• Narrow therapeutic window, drug and electrolyte (particularly potassium) levels must be monitored, kidneys must be working
• Cardiovascular: Dysrhythmias (bradycardia or tachycardia)
• CNS: Headaches, fatigue, confusion, convulsions
• Eye: Colored vision (seeing green, yellow, purple), halos, flickering lights
• GI: Anorexia, nausea, vomiting, diarrhea

Digoxin Toxicity

• Digoxin toxicity is treated with digoxin immune Fab (Digibind) therapy.
• Conditions that predispose patients to Dig toxicity include hypokalemia, use of cardiac pacemaker, hepatic dysfunction, hypercalcemia, dysrhythmias, and advanced age.

Loop Diuretics

• Furosemide, torsemide, and bumetanide manage edema associated with HF.
• Decreases plasma volume by promoting excretion of fluid, sodium, and potassium.
• Works well with decreased kidney function.
• Decreases Systemic Vascular Resistance, Pulmonary Vascular Resistance, Blood Pressure, Central Venous Pressure, and Left ventricular end diastolic pressure

Miscellaneous Drugs to Treat Heart Failure

• 'hydralazine/isosorbide dinitrate (BiDil)
• This was the First drug approved for a specific ethnic group, for African Americans with diuresis and increased contractility.
• dobutamine Beta1-selective vasoactive adrenergic drug, Structurally similar to dopamine which helps: improve Squeeze & frequency of HR

Heart Failure Drugs: Nursing Implications

• nesiritide, milrinone, dopamine,
• Use an infusion pump and Monitor I& O, heart rate and rhythm, BP, daily weights, and respirations and:
• Assess clinical parameters that include weight I& O measures, ECG, & serum level electrolytes i.e. potassium, sodium, magnesium, calcium, renal, and studies on liver function.
• Before giving any dose that influences HR, count apical pulse for 1 full minute.
• For apical pulse less than 60 or greater than 100 beats/minute: Hold dose and Notify prescriber.
• Hold dose and notify prescriber if patient experiences signs or symptoms of toxicity ○ Including Visual disturbances indicated by blurred vision, seeing green or yellow halos around objects

More Nursing Implications for Heart Failure

• Don't give digoxin with high-fiber foods, because fiber binds with digitalis
• Tell patients to report a weight gain of 2 or more pounds quickly, to stay ahead of symptoms of Heart Failute
• Monitor for therapeutic effects that show they are working such as, Increased urinary output, Decreased edema, shortness of breath, dyspnea, crackles, fatigue, Resolution of paroxysmal nocturnal dyspnea, and Improved peripheral pulses, skin color, temperature, and for adverse effects.

SDOH (Social determinants of health)

• SDOH factors associated with higher readmissions include the county in which the hospital is located and personal and social factors such as disability status, race, ethnicity, insurance, and income inequality.
• In the healthcare delivery system, patients who are food insecure, struggle with transportation, and have less access to medications, education, and health services have poorer health outcomes.
• SDOH impact an individual's physical and mental well-being and affect how they perceive and experience care in the health system, community, and home.