Week 6 Cardiac B

Introduction to Heart Failure

• Heart failure (HF) is a debilitating condition where the heart's ability to pump effectively is reduced, leading to decreased cardiac output.
• However, with proper management, symptoms and complications can be reduced.
• A heart failure diagnosis is based on clinical signs and symptoms, including:
  • Dyspnoea (shortness of breath)
  • Fatigue
  • Limited exercise tolerance
  • Fluid retention, potentially causing pulmonary congestion and peripheral oedema
• The National Heart Foundation (Australia; 2018) defines heart failure as:
  • A complex clinical syndrome with typical symptoms and signs that generally occur on exertion, but can also occur at rest (particularly when recumbent).
  • Secondary to an abnormality of cardiac structure or function that impairs the ability of the heart to fill with blood at normal pressure or eject blood sufficient to fulfill the needs of the metabolising organs.

Learning Outcomes

• Understand the underlying pathophysiology of heart failure
• Discuss the clinical manifestations of heart failure
• Discuss the pharmacological treatment and management for heart failure
• Demonstrate and perform a patient-centred assessment of a patient with heart failure
• Discuss the diagnostic tests required for heart conditions
• Discuss cardiac rehabilitation and interprofessional collaboration

Cardiac Function Revision

• Cardiac output (CO) measures the heart's effectiveness.
• Cardiac output is the volume of blood pumped out of the heart each minute.
• CO = HR oldsymbol{x} SV
  • HR (heart rate): Beats per minute
  • SV (stroke volume): Volume (mLs) per beat
• Stroke volume is affected by:
  • Preload:
    • End-diastolic volume (volume of blood in the ventricles just before contraction) and associated pressure.
    • Influenced by venous return (blood returning to the heart) and ventricular compliance (ability to stretch).
  • Afterload:
    • Resistance the ventricle must overcome to eject blood into the arteries.
    • The pressure in each left and right ventricle must exceed the pressure within the aorta and pulmonary arteries respectively
    • Hypertension increases workload because the heart needs greater force to overcome high arterial pressures.
  • Contractility:
    • Force of myocardial contraction.
    • Influenced by ventricular myocardial stretch (Frank-Starling mechanism), sympathetic nervous system activation (enhances contraction), and myocardial oxygen supply (essential for contraction strength).
• Ejection Fraction (EF):
  • Measures how effectively the heart is pumping.
  • Determines the type of heart failure.
  • Typically estimated via echocardiography, or through invasive hemodynamic monitoring.
  • Normal EF: 50-70%.
  • Reduced values indicate compromised cardiac function.

Overview of Heart Failure

• Heart failure is characterized by abnormal ventricular function, leading to inefficient myocardial performance and compromised ability to meet the body's metabolic demands.
• Leads to inadequate tissue perfusion and volume overload.
• Statistics:
  • Approximately 144,000 Australians (0.6% of the population) live with heart failure.
  • Heart failure accounts for almost 1 in 50 deaths, equating to approximately 9 deaths per day (one person every 2.5 hours).
  • About 170 people are hospitalised every day with heart failure (about 1 person every 9 minutes).

Classification and Staging

• New York Heart Association (NYHA) classification: Based on tolerance to physical activity.
• American College of Cardiology and American Heart Association (ACC/AHA) stages: Identifies four stages of heart failure.
• These classifications provide an understanding of a patient's heart failure diagnosis and its impact on activities of daily living.

Pathophysiology of Heart Failure

• Heart failure occurs when the heart cannot pump enough oxygen and nutrients to meet the body's needs.
• Common causes: coronary heart disease, heart attacks (acute myocardial infarction), or high blood pressure (hypertension).

Factors Contributing to Heart Failure

• Preload
  • Increased volume/filling prior to systole
  • LV=left ventricle; LVEDP=left ventricular end-diastolic pressure; RV=right ventricle; ADH=anti-diuretic hormone
• Afterload
  • Increased workload on the heart i.e. hypertension

Types of Heart Failure

• Heart Failure Terminology:
  • Can be chronic or acute.
  • Largely broken down into left and right sided heart failure.
  • Refers to either the left or right side of the heart unable to meet the cardiac output demands for perfusion.
  • Some experience both left and right sided heart failure together.
• Right Ventricle:
  • Greater sensitivity to afterload changes, leading to dilatation to preserve stroke volume.
  • Right ventricular myocardium requires less muscle power than the left ventricular myocardium.
  • More compliant to accommodate larger variations in venous return without altering end-diastolic pressure
• Right-Sided Heart Failure Common Causes:
  • Respiratory conditions (e.g., pulmonary hypertension, chronic lung disease) that increase the right ventricle’s workload
  • Left-sided heart failure, which can lead to right-sided failure due to increased pulmonary pressure.
• Left heart failure was commonly referred to as congestive cardiac failure (CCF).
• Left heart failure:
  • Defined by ejection fraction.
• Heart Failure with REDUCED Ejection Fraction (HFrEF):
  • Formerly referred to as systolic heart failure.
  • The left ventricular systolic function reduces, leading to poor contraction and emptying of the left ventricle during systole.
  • Fluid builds up in the blood vessels, leaking into the interstitial spaces of the lungs and body leading to oedema, orthopnoea and shortness of breath.
  • Less than 40% of the available blood is pumped out.
• Heart Failure with PRESERVED Ejection Fraction (HFpEF):
  • Formerly referred to as diastolic heart failure.
  • Heart failure symptoms with a preserved ejection fraction of 50% or higher.
  • Decreased compliance of the left ventricle results in poor filling.
  • The left ventricle becomes stiff and thickened, making it harder to fill with blood during diastole (the heart's relaxing phase).
  • Even though less blood fills the ventricle, most of it is pumped out, so the ejection fraction remains normal.
• Right-Sided Heart Failure:
  • Occurs from impaired contractility of the right ventricle (RV) caused by increased pressure, volume overload, intrinsic myocardial contratility dysfunction and/ or cardiac arrhythmias.
  • Often caused from left heart failure.
  • Commonly caused by pulmonary diseases such as COPD and cystic fibrosis.
  • Can also be caused by right ventricle myocardial diseases such as right ventricle ischaemia or infarction, infiltrative disease (sarcoidosis), cardiomyopathy and microvascular disease.

Compensatory Mechanisms

• Compensatory mechanisms are used to maintain cardiac output and perfusion:
  • Sympathetic nervous system activation: Increases heart rate and blood pressure.
  • Neurohormonal responses: Releases hormones that cause blood vessels to narrow and retain fluids.
  • Ventricular dilation: The heart stretches to hold more blood.
  • Ventricular hypertrophy: The heart muscle thickens to pump harder.
  • Ventricular remodeling: Changes in heart size and shape that can worsen heart failure.
  • Counter-regulatory mechanisms: Beneficial responses that try to balance these effects.
• These compensatory processes can worsen heart damage over time.
• Left-sided failure often causes lung symptoms; right-sided failure causes body-wide swelling

Clinical Manifestations

• Patients diagnosed with heart failure typically have abnormal ventricular function.
• The Heart Foundation identify the following potential signs and symptoms:
• Differences in symptomatology between the left and right sided heart failure.
• HFrEF often present with signs of pulmonary oedema (pulmonary vascular congestion) and inadequate perfusion of the systemic circulation:
  • Fatigue, dyspnoea, orthopnoea, cough (with frothy sputum), decreased urine output and oedema.
• HFpEF often present with:
  • Dyspnoea on exertion, fatigue and pulmonary oedema (venous congestion in the lungs).

Chronic Heart Failure

• Chronic heart failure is a progressive decline in ventricular function coupled with chronic neurohormonal activation resulting in ventricular remodelling that encompasses changes in the size, shape and mechanical efficacy of the ventricles.
• As a patient progresses through the stages and into chronic heart failure, they may exhibit signs and symptoms of both left and right heart failure.
  • Fatigue
  • Dyspnoea
  • Tachycardiac
  • Oedema
  • Nocturia (Frequent night time urination)
  • Skin changes
  • Behavioural changes
  • Chest pain
  • Weight changes

Complications from Heart Failure

• Patients that have heart failure are at risk of associated complications to the heart itself, liver, lungs and kidneys.

Nursing Assessment and Management

• For patients with heart failure, a primary and secondary assessment and vital signs are completed as part of an admission assessment, start of shift and/or as clinically indicated.

Subjective data

• Important health information
  • History of present illness: current symptoms, what bought the patient to seek healthcare
  • Past health history: CHD, hypertension, cardiomyopathy, valvular or congenital heart disease, diabetes mellitus, renal disease, dyslipidaemia, thyroid or lung disease, rapid or irregular heart rate.
  • Medications: Use of and adherence to any heart medications, use of diuretics, oestrogens, corticosteroids, non-steroidal anti-inflammatory agents, OTC medication or herbal medication
  • In a focused cardiovascular assessment you may find some of the following changes:
    • Integumentary
    • Cool, diaphoretic skin, cyanosis, pallor, peripheral oedema
    • Respiratory
    • Tachypnoea, crackles, rhonchi, wheezes, frothy, blood-tinged sputum
    • Cardiovascular
    • Tachycardia, murmurs, abnormal heart sounds, jugular venous distention
    • Neurological
    • Mental Status changes, confusion, restlessness. decreased attention or memory
    • Gastrointestinal
    • Abdominal distention, hepatosplenomegaly, ascites
    • Renal
    • Poor urine output
  • Functional Health patterns
    • Health perception-health management: fatigue, depression, anxiety
    • Nutritional- metabolic: Usual sodium intake, nausea, vomiting, anorexia, stomach bloating, weight gain, ankle swelling
    • Elimination: Nocturia, decrease day time urine output, constipation
    • Activity-exercise: Fatigue; dyspnoea, orthopnoea, cough, palpitations, dizziness, fainting
    • Sleep-rest pattern: paroxysmal nocturnal dyspnoea, number of pillows needed to sleep at night, insomnia
    • Cognitive-perceptual: chest pain or heaviness, RUQ pain, abdominal discomfort, behavioural changes, vision changes.
    • Possible diagnostic findings
      • Abnormal serum electrolytes (esp sodium and potassium); ↑ serum urea, creatinine, increased liver function tests, increased BNP or ANP markers, chest x-ray demonstrating cardiomegaly, pulmonary congestion and interstitial pulmonary oedema, echocardiogram showing increased chamber size, decreased wall motion, ejection fraction reduced or normal with diastolic changes, and decreased oxygen saturation.

Nursing Management

• The main goals in the treatment of chronic heart failure are to treat the underlying cause and contributing factors; to maximise cardiac output reduce symptoms improve ventricular function improve quality of life preserve target organ function improve mortality and morbidity risks.
  • Non-pharmacological management of heart failure can include:
    • Multidisciplinary heart failure program: referral to a multidisciplinary heart failure program for patients with heart failure and high risk factors.
    • Nurse-led titration clinics: nurse-led titration programs can be recommended in patients who have not reached maximum doses of heart failure medication to decrease hospitalisations.

Nursing Education Self Management

• Educating patients and their carers about self-management of heart failure is recommended to decrease hospitalisation and mortality.
  • Dietary Therapy
  • A diet plan with a list of permitted and restricted foods
  • Examine labels (food and OTC medications) for sodium content.
  • Avoid the use of salt when cooking
  • Daily weigh (at the same time each day, preferably in the morning)
  • Eat smaller, more frequent meals
  • Activity Program/exercise
    • Increase walking and other activities
    • Consider a cardiac rehabilitation program
    • Avoid extreme cold and hot
• Ongoing monitoring
  • Know the signs and symptoms of worsening heart failure
  • Recall symptoms experienced
  • Report to the healthcare team any of the following:
    • weight gain of 1.5kg in 2 days, or 2.3kg in 1 week, difficulty breathing, waking up breathless at night, frequent dry cough, swelling of ankles, feet or abdomen, nausea with swelling, pain or tenderness, dizziness or fainting
  • Attend regular check-ups with healthcare team
  • Consider joining a support group
  • Health promotion
  • Annual flu vaccine
  • Pneumococcal vaccine
  • Develop plan to reduce risk factors
  • Rest
    • Plan a regular daily rest and activity program
    • After exertion, (exercise and ADL's) plan a rest period.
    • Avoid exertion around meal times. (This is an important aspect of planning your nursing care for patients experiencing exacerbations of heart failure). Blood is diverted to the GIT post meals so it is wise to avoid exertional activities immediately after meals.
    • Avoid emotional upsets, verbalise concerns, fear and feelings of depression to the health care team.
  • Medication therapy
    • Take medication as prescribed
    • Develop a system to ensure medications are taken
    • Take pulse rate each day and know the parameters that your healthcare provider wants for your heartrate
    • Take BP at determined intervals and know BP limits
    • Know signs and symptoms of orthostatic hypotension and how to prevent them
    • Know signs and symptoms of internal bleeding and what to do about it if taking anticoagulants.
    • Know INR levels if taking warfarin

Nursing Implementation

• The National Heart Foundation of New Zealand and Australia and Cardiac Society of Australia and New Zealand have selected guidelines in the management of patients with heart failure to reflect evidenced-based standards of care.
• Communication and jointed decision making with the patients and/or carers
• Acute intervention
  • Patients with heart failure may experience periods of worsening and acute exacerbations. This requires stabilisation and specialised monitoring and care.
• Support systems need to be in place upon discharge
• Ambulatory and home care
  • Often led and monitored by heart failure specialty nurses and/or nurse practitioners
  • Focus on slowing the progression of the disease
  • Focus on managing patients out of hospital
• Palliative and end-of-life care
  • Refer patients with advanced heart failure to palliative care
  • Goals of providing comfort and relieving symptoms remain priorities in the care of patients

Heart Failure Pharmacology

• In 2018, the National Heart Foundation of Australia and Cardiac Society of Australia and New Zealand [NHFACSANZ], developed guidelines for the prevention, detection and management of Heart Failure (HF) in Australia.

Prevention

• Prevention centres around the management of blood pressure and serum cholesterol levels.
• Medications used to control BP and for patients with left ventricular (LV) systolic dysfunction to prevent heart failure include:
  • ACE inhibitors
  • Beta blockers

Sodium-glucose cotransporter 2 (SGLT2) inhibitors

• for patients with T2 diabetes.
• SGLT-2 inhibitors have multiple effects and have generally been used for diabetes, however, research has indicated that they can also improve heart function.
  • SGLT2 Inhibitors:
    • Dagagliflozin
    • Empagliflozin
    • Hypercholesterolaemia is a risk factor for a number of cardiovascular conditions.

Management

• The NHFACSANZ guidelines mentioned above indicate a combined use of ACE inhibitors, beta-blockers and a potassium sparing diuretic (also known as mineralocorticoid receptor antagonist [MRA]) which would decrease mortality by 1-3 years.
• In some cases, this combination may fail in its effectiveness, or patients may not tolerate the combination.
• In these situations, the use of an angiotensin receptor neprilysin inhibitor (ARNI) combination may be used.
• In patients that do not or no longer respond to first line treatment of HF, then digoxin may be considered even in the absence of an arrhythmia.
• Diuretics
  • Loop Diuretics
    • Furosemide
    • Bumetanide
  • Potassioum Sparing Diuretics
    • Spironolactone
• Angiotensin Receptor Neprilysin Inhibitor (ARNI)
  • Sacubitril with Valsartan

Interprofessional Collaboration

Roles of Interprofessional Team Members in Cardiac Care

• Pharmacists
  • Verify current medications, educate patients, provide medication summaries, and offer expertise on medication-food interactions and adherence.
• Dieticians
  • Provide dietary guidance and personalized meal plans for heart-healthy eating.
• Physiotherapists
  • Support recovery by improving muscle strength, reducing fatigue, and developing safe exercise plans, including cardiac rehabilitation.
• Occupational Therapists
  • Assist with returning to daily activities and work, recommend home modifications for safety, and offer energy conservation strategies.
• Social Workers
  • Provide emotional support, assist with accessing community services, and help navigate financial, legal, and insurance concerns.
• General Practitioners
  • Provide ongoing care, manage risk factors, and coordinate referrals, monitoring heart function, blood pressure, cholesterol, and kidney function.
• Cardiologist
  • Provide expert assessment, diagnosis, and management of complex heart conditions, leading specialized treatments.
• Clinical Nurse Specialists/Nurse Practitioners
  • Monitor patient progress, provide education, perform key assessments, and coordinate care plans, especially during discharge planning.
• Palliative care consultant/team
  • Focus on symptom management, improving quality of life, and providing comfort care in advanced heart failure.
• Mental Health Professionals
  • Help patients and families cope with anxiety, depression, or stress related to their diagnosis and assist with emotional adjustments to lifestyle changes.

Diagnostics and Treatment

Medical Assessment

• Thorough health history and physical examination.
• Determine the underlying cause.

Diagnostic Studies

• Blood studies
  • Cardiac markers (troponin and creatinine kinase [CK])
  • Electrolytes (sodium, potassium, calcium, magnesium)
  • Renal function (estimated glomerular filtration rate [eGFR], urea and creatinine)
  • Blood glucose
  • C-reactive protein (CRP), homocysteine
  • Full blood count, white cell count, haemoglobin
  • Activated partial thromboplastin time (aPTT), international normalised ration (INR)
  • Natriuretic peptides (B-type, N-terminal pro- brain [BNP and ANP markers])
  • Liver function tests
  • Serum lipids (cholesterol, triglycerides, lipoproteins [HDL, LDL])
  • ABG
• Radiology
  • Chest x-ray, echocardiogram (ECHO)
  • Transoesophageal echocardiogram, nuclear imaging
  • 12-lead ECG, Holter monitoring, telemetry, exercise (stress) testing
• Computerised Tomography (CT) and Magnetic Resonance Imaging (MRI)
  • Cardiovascular MRI, magnetic resonance angiography, cardiac CT, coronary CT angiography.
• Invasive studies
  • Cardiac catheterisation, coronary angiography (examine the coronary arteries)
  • Intracoronary ultrasound, fractional flow reserve, electrophysiology study
  • Peripheral arteriography and venography, myocardial biopsy, haemodynamic monitoring.