Heart Failure

Heart Failure 150 150 Tony Guo

Heart Failure

 

  • Complex clinical syndrome resulting in insufficient blood supply/oxygen to tissues and organs
    • Involves diastolic or systolic dysfunction
    • Ejection fraction (EF) is amount of blood pumped by LV with each heart beat
  • Associated with CVDs
  • Increase in incidence and prevalence
  • Most common cause for hospital admission in adults over age 65

 

Risk factors

  • Primary risk factors
    • Hypertension 
      • Modifiable risk factor
      • Properly treated and managed, incidence of HF can be reduced by 50%
    • CAD
  • Co-morbidities contribute to development of HF

 

Etiology of Heart failure

  • Anything that interferes with mechanisms that regulate cardiac output (CO)
  • Primary causes
    • Conditions that directly damage the heart
      • Hypertension, including hypertensive crisis
      • Coronary artery disease, including myocardial infarction
      • Rheumatic heart disease
      • Congenital heart defects (e.g., ventricular septal defect)
      • Pulmonary hypertension
      • Cardiomyopathy (e.g., viral, postpartum, substance abuse)
      • Hyperthyroidism
      • Valvular disorders (e.g., mitral stenosis)
      • Myocarditis
  • Precipitating causes
    • Conditions that increase workload of ventricles
Cause Mechanism
Anemia  Decrease O2-carrying capacity of the blood stimulating

Increase in CO to meet tissue demands, leading to increase in cardiac workload and increase in size of LV

Infection  Increased O2 demand of tissues, stimulating increase CO
Thyrotoxicosis Changes the tissue metabolic rate, increased HR and workload of the heart
Hypothyroidism Indirectly predisposes to increased atherosclerosis.

Severe hypothyroidism decreases myocardial contractility.

Dysrhythmias May decreased CO and increased workload and O2 requirements of myocardial tissue
Bacterial endocarditis Infection: increased metabolic demands and O2 requirements

Valvular dysfunction: causes stenosis or regurgitation

Obstructive sleep apnea Frequent nighttime apnea results in increased afterload, intermittent hypoxia, and increased sympathetic nervous system activity.
Pulmonary embolism Increased pulmonary pressure resulting from obstruction leads to pulmonary hypertension, decreased CO.
Paget’s disease Increased workload of the heart by increased vascular bed in the skeletal muscle
Nutritional deficiencies May decrease cardiac function by increased myocardial muscle mass and myocardial contractility
Hypervolemia Increased preload causing volume overload on the RV

 

Gender differences

  • Men
    • Men experience systolic failure more frequently than women.
    • Men with asymptomatic systolic failure experience greater mortality benefit from ACE inhibitor therapy than women.
  • Women
    • Women experience diastolic failure more frequently than men.
    • Women have a higher risk of ACE inhibitor–related cough than men.
    • Women experience more digitalis-related death than men.
    • Women with diabetes are more predisposed to HF than men.

 

Classification of heart failure

  • Left-sided HF
    • Most common form of HF
    • Results from inability of LV to
      • Empty adequately during systole
      • Fill adequately during diastole
    • Further classified as
      • Systolic
      • Diastolic
      • Mixed systolic and diastolic
    • Blood backs up into left atrium and pulmonary veins
    • Increased pulmonary pressure causes fluid leakage →→ pulmonary congestion and edema

 

Pathophysiology

  • Systolic heart failure
    • HFrEF – HF with reduced EF
    • Inability to pump blood forward
    • Caused by
      • Impaired contractile function 
      • Increased afterload 
      • Cardiomyopathy
      • Mechanical abnormalities 
    • Decreased LV ejection fraction (EF)
  • Diastolic heart failure
    • HFpEF – HF with preserved EF
    • Impaired ability of the ventricles to relax and fill during diastole, resulting in decreased stroke volume and CO
    • Result of left ventricular hypertrophy from hypertension, older age, female, diabetes, obesity
    • Same end result as systolic failure
  • Mixed heart failure
    • Mixed systolic and diastolic failure
      • Seen in disease states such as dilated cardiomyopathy (DCM)
      • Poor EFs (<35%)
      • High pulmonary pressures
      • Biventricular failure 
        • Both ventricles may be dilated and have poor filling and emptying capacity
  • Right-sided heart failure
    • RV fails to pump effectively
    • Fluid backs up in venous system
    • Fluid moves into tissues and organs
    • Left-sided HF is most common cause
      • Other causes include RV infarction, PE, and cor pulmonale (RV dilation and hypertrophy)
  • Heart failure
    • Ventricular failure leads to:
      • Low blood pressure (BP)
      • Low CO
      • Poor renal perfusion
    • Abrupt or subtle onset
    • Compensatory mechanisms mobilized to maintain adequate CO.

 

Compensatory mechanism

  • Renin-Angiotensin-Aldosterone-System (RAAS)
  • Neurohormonal response – RAAS
  • Endothelin release (contractility)
  • Cytokine release (Hypertrophy)
  • Inadequate stroke volume and CO –  (Epi and NoreEpi)
  • Ventricular remodeling
    • Continuous activation of neuro-hormonal responses (RAAS and SNS)
    • Hypertrophy of ventricular myocytes
    • Ventricles larger but less effective in pumping
    • Can cause life-threatening dysrhythmias and sudden cardiac death
  • Dilation
    • Enlargement of chambers of heart that occurs when pressure in left ventricle is elevated
    • Initially effective
    • Eventually this mechanism becomes inadequate and CO decreases
  • Hypertrophy 
    • Increase in muscle mass and cardiac wall thickness
    • Initially effective
    • Over time leads to poor contractility, increased O2 needs, poor coronary artery circulation, and risk for ventricular dysrhythmias

Counterregulatory mechanism

  • Natriuretic peptides
    • Atrial natriuretic peptide (ANP),
      b-type natriuretic peptide (BNP)
    • Released in response to increased blood volume in heart
    • Causes diuresis, vasodilation, and lowered BP
    • Counteracts effects of SNS and RAAS
  • Nitric oxide (NO) and prostaglandin
    • Released from vascular endothelium in response to compensatory mechanisms 
    • NO and prostaglandin relaxes arterial smooth muscle, resulting in vasodilation and decreased afterload

 

Acute Decompensated Heart Failure

  • Clinical manifestation
    • ADHF
      • Sudden onset of signs and symptoms of HF
      • Requires urgent medical care
      • Pulmonary and systemic congestion due to increased left-sided and right-sided filling pressures
    • Early → increased pulmonary venous pressure
      • Increase in the respiratory rate 
      • Decrease in PaO2 
    • Later → interstitial edema
      • Tachypnea 
    • Further progression → alveolar edema
      • Respiratory academia
    • Can manifest as pulmonary edema
    • Life-threatening situation – alveoli fill with fluid
    • Most commonly associated with left-sided HF

 

Right-sided heart failure Left-sided heart failure
Signs
RV heaves LV heaves
Murmurs Pulsus alternans (alternating pulses: strong, weak)
Jugular venous distention Increased HR
Edema (e.g., pedal, scrotum, sacrum) PMI displaced inferiorly and left of the midclavicular line (LV hypertrophy)
Weight gain Decreased PaO2, slight increased PaCO2 (poor O2 exchange)
Increased HR Crackles (pulmonary edema)
Ascites S3 and S4 heart sounds
Anasarca (massive generalized body edema) Pleural effusion
Hepatomegaly (liver enlargement) Changes in mental status
Restlessness, confusion
Symptoms
Fatigue Weakness, fatigue
Anxiety, depression Anxiety, depression
Dependent, bilateral edema Dyspnea
Right upper quadrant pain Shallow respirations up to 32-40/min
Anorexia and GI bloating Paroxysmal nocturnal dyspnea
Nausea Orthopnea
Dry, hacking cough
Nocturia
Frothy, pink-tinged sputum (advanced pulmonary edema)

 

Chronic heart failure

  • Clinical manifestation
    • Dependent on age, underlying type and extent of heart disease, and which ventricle is affected
    • FACES
      • Fatigue
      • Limitation of Activities
      • Chest congestion/cough
      • Edema
      • Shortness of breath
    • Fatigue 
    • Dyspnea 
    • Orthopnea
    • Paroxysmal nocturnal dyspnea
    • Tachycardia
    • Edema 
    • Dependent, liver, abdominal cavity, lungs
    • Edema may be pitting in nature 
    • Sudden weight gain of >3 lb (1.4 kg) in 2 days may indicate ADHF, an exacerbation of chronic HF
    • Nocturia
  • Edema 
    • Dependent, liver, abdominal cavity, lungs
    • Edema may be pitting in nature 
    • Sudden weight gain of >3 lb (1.4 kg) in 2 days may indicate ADHF, an exacerbation of chronic HF
  • Nocturia

 

Heart failure 

  • Complications
    • Pleural effusion
    • Dysrhythmias – atrial and ventricular
    • Left ventricular thrombus
    • Hepatomegaly
    • Renal failure

 

  • Diagnostic studies
    • Determine and treat underlying cause
    • Echocardiogram
      • Provides information on EF, heart valves and heart chambers
    • ECG, chest x-ray, 6-minute walk test, MUGA scan, cardiopulmonary exercise stress test, heart catheterization, EMB
    • BNP levels

 

ADHF

  • Interprofessional care
    • Continuous monitoring and assessment
      • VS, O2 saturation, urinary output
    • Hemodynamic monitoring if unstable 
    • Supplemental oxygen
    • Mechanical ventilation if unstable
    • High Fowler’s position
    • Ultrafiltration (aquapheresis) for patients with volume overload and resistance to diuretics
    • Circulatory assist devices for patients with deteriorating HF
      • Intra-aortic balloon pump (IABP)
      • Ventricular assist devices (VADs)
  • Drug therapy
    • Diuretics
      • Decrease volume overload (preload)
        • Loop diuretics – Furosemide (Lasix)
    • Vasodilators
      • Reduce circulating blood volume and improve coronary artery circulation
        • IV nitroglycerin
        • Sodium nitroprusside 
        • Nesiritide (Natrecor)
    • Morphine
      • Reduces preload and afterload
      • Relieves dyspnea and anxiety
    • Positive inotropes
      • β-agonists (dopamine, dobutamine, norepinephrine  [Levophed])
      • Phosphodiesterase inhibitor (milrinone)
      • Digitalis

Chronic HF

  • Interprofessional care
    • Main treatment goals
      • Treat the underlying cause and contributing factors
      • Maximize CO
      • Reduce symptoms
      • Improve ventricular function
      • Improve quality of life
      • Preserve target organ function
      • Improve mortality and morbidity
    • Oxygen therapy
      • Relieves dyspnea and fatigue
    • Physical and emotional rest
      • Conserve energy and decrease oxygen needs
      • Dependent on severity of HF
    • Structured exercise program
      • CR associated with better outcomes
    • CardioMems system
    • Implantable cardioverter-defibrillator (ICD)
    • Biventricular pacing/cardiac resynchronization therapy (CRT)
    • IABP and VADs as bridge to transplant (BTT) or as destination therapy (DT)
  • Drug therapy
    • Diuretics
      • Reduce edema, pulmonary venous pressure, and preload
      • Promote sodium and water excretion
      • Loop diuretics 
      • Thiazide diuretics 
      • Monitor potassium levels (hypokalemia)
    • RAAS inhibitors
      • ACE inhibitors 
      • Angiotensin II receptor blockers 
      • Aldosterone antagonists
      • Monitor potassium levels (hyperkalemia)
    • β-Blockers
    • Vasodilators
      • Nitrates
    • Combination therapy
      • BiDil
    • Positive inotropic agents 
      • Digitalis
    • Inhibitor of cardiac sinus node
      • Ivabradine (Corlanor)
      • Must be in sinus rhythm with resting HR of > 70 bpm and taking highest dose β-blockers
        • Inhibits sinus node
        • Reduces HR
        • Decreases risk of hospitalization for worsening HF
  • Nutritional therapy
    • Low sodium diet
    • Individualize recommendations and consider cultural background www.nhlbi.nih.gov/health/index.htm#recipes
    • Recommend Dietary Approaches to Stop Hypertension (DASH) diet 
    • Sodium is usually restricted to 2 g/day
    • Fluid restriction not generally required
    • If required, < 2L/day
      • Ice chips, gum, hard candy, ice pops to help thirst
    • Daily weights important
      • Same time, same clothing each day
    • Weight gain of 3 lb (1.4 kg) over 2 days or a 3- to 5-lb (2.3 kg) gain over a week should be reported to HCP

 

Nursing management: Heart Failure

  • Nursing Assessment
    • Subjective data
      • Health information
        • Past health history: 
          • CAD (including recent MI)
          • Hypertension
          • Cardiomyopathy
          • Valvular or Congenital heart disease
          • Diabetes mellitus
          • Hyperlipidemia
          • Renal disease
          • Thyroid or lung disease
          • Rapid or irregular heart rate
        • Medications: 
          • Use of and adherence with any heart drugs. 
          • Use of diuretics, estrogens, corticosteroids, nonsteroidal anti-inflammatory drugs, over-the-counter drugs, herbal supplements
      • Functional health pattern
        • Health perception–health management: 
          • Fatigue, depression, anxiety
        • Nutritional-metabolic: 
          • Usual sodium intake. Nausea, vomiting, anorexia, stomach bloating. Weight gain, ankle swelling
        • Elimination: 
          • Nocturia, decreased daytime urine output, constipation
        • Activity-exercise: 
          • Dyspnea, orthopnea, cough (e.g., dry, productive). Palpitations, dizziness, fainting
        • Sleep-rest: 
          • Number of pillows used for sleeping. Paroxysmal nocturnal dyspnea, insomnia, sleep apnea
        • Cognitive-perceptual: 
          • Chest pain or heaviness. RUQ pain, abdominal discomfort. Behavioral changes, visual changes
    • Objective data
      • Integumentary
        • Cool, diaphoretic skin. Cyanosis or pallor. Peripheral edema (right-sided heart failure)
      • Respiratory
        • Tachypnea, crackles, wheezes. Frothy, blood-tinged sputum 
      • Cardiovascular
        • Tachycardia, S3, S4, murmurs. Pulsus alternans. PMI displaced inferiorly and posteriorly, lifts and heaves, jugular venous distention
      • Gastrointestinal
        • Abdominal distention, hepatosplenomegaly, ascites
      • Neurologic
        • Restlessness, confusion, decreased attention or memory
      • Possible Diagnostic Findings
        • Altered serum electrolytes (especially Na+ and K+)
        • Increased BUN, creatinine, or liver function tests
        • Increased NT-proBNP or BNP
        • Chest x-ray demonstrating cardiomegaly, pulmonary congestion, and interstitial pulmonary edema. 
        • Echocardiogram showing increased chamber size, decreased wall motion, decreased EF or normal EF with evidence of diastolic failure. 
        • Atrial and ventricular enlargement on ECG. 
        • Decreased O2 saturation
  • Nursing Diagnoses
    • Impaired gas exchange related to increased preload and alveolar-capillary membrane changes
    • Decreased cardiac output related to altered contractility, altered preload, and/or altered stroke volume
    • Excess fluid volume related to increased venous pressure and decreased renal perfusion secondary to heart failure
    • Activity intolerance related to imbalance between O2 supply and demand secondary to cardiac insufficiency and pulmonary congestion
  • Nursing planning
    • Overall Goals
      • Decrease in symptoms 
      • Decrease in peripheral edema
      • Increase in exercise tolerance
      • Compliance with the treatment regimen
      • No complications related to HF
  • Nursing intervention
    • Monitor respiratory status
    • Administer oxygen therapy
    • Semi-Fowler’s position
    • Monitor hemodynamic status
    • Daily weights
    • I and O
    • Administer prescribed drugs
    • Monitor edema
    • Alternate rest with activity
    • Provide diversionary activities
    • Monitor response to activity
    • Collaborate with OT/PT
    • Reduce anxiety
    • Evaluate support system
    • Patient teaching
      • Signs and symptoms of HF exacerbations – what to do/report
      • Importance of early detection
      • Can have positive outlook with chronic health problem if treatment plan is followed
      • Drug therapy
        • Expected actions 
        • Signs of drug toxicity
        • How to take HR and what to report
        • Signs and symptoms of hypokalemia and hyperkalemia
        • BP monitoring as needed
      • Dietary therapy
        • Dietary therapy
        • Written plan 
        • Reading labels for sodium 
        • No added salt
        • Daily weights
        • Smaller, more frequent meals
      • Activity/rest
        • Energy-conserving and energy-efficient behaviors
        • Exercise training (cardiac rehab)
        • Increase gradually
        • Avoid heat and cold extremes
        • Rest after exertion
        • Avoid emotional upsets
      • Ongoing monitoring
        • Know FACES
        • Reappearance of symptoms
        • What to report
          • Weight gain of 3 lb (1.4 kg) in 2 days, or 3-5 lb (2.3 kg) in a wk
          • Difficulty breathing, especially with activity or when lying lat
          • Waking up breathless at night
          • Frequent dry, hacking cough, especially when lying down
          • Fatigue, weakness
          • Swelling of ankles, feet, or abdomen. Swelling of face or difficulty breathing (if taking ACE inhibitors)
          • Nausea with abdominal swelling, pain, and tenderness
          • Dizziness or fainting
        • Regular follow-up
        • Support group
      • Health promotion
        • Vaccinations
          • Annual flu vaccination
          • Pneumococcal vaccine
        • Reduce risk factors
    • Ambulatory Care
      • Explain to patient and caregiver physiologic changes that have occurred 
      • Assist patient to adapt to both physiologic and psychologic changes
      • Include patient and caregiver(s) in overall care plan
  • Nursing evaluation
    • Monitoring to assess outcomes and prevent/ limit future hospitalizations
      • Vital signs
      • Weight
      • Pulse oximetry
      • Dyspnea
    • Home health nurses can be essential
    • Can use electronic monitoring

 

Heart Transplantation

  • Treatment of choice for patients with refractory end-stage HF, inoperable CAD, and cardiomyopathy
    • 3,000 on list; average 2,000 available
    • Survival rate of 85%-90% at 1year; 75% at 3
  • Selection process identifies patients who would most benefit from a new heart  
  • Candidates must undergo physical, diagnostic, and psychologic evaluation
  • Transplant candidates are placed on a list 
    • Stable patients wait at home and receive ongoing medical care 
    • Unstable patients may require hospitalization for more intensive therapy
    • Overall waiting period for a heart is long; many patients die during this time
  • Heart retrieval first step
  • Second step is removal of recipient’s heart except for portions of atria (2 different approaches) and venous connections
  • Final step is implantation of donor heart

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