Heart failure

Heart failure is a pathological state in which the myocardium is unable to sustain adequate cardiac output, or can only do so by increasing ventricular filling pressures significantly. Cardiovascular diseases (CVDs) constitute a spectrum of pathologies involving the heart and the vascular system.
They encompass:
  • Coronary artery disease: Pathology of the coronary arteries impairing myocardial perfusion.
  • Cerebrovascular disease: Disorders of the cerebral vasculature affecting cerebral blood flow.
  • Peripheral artery disease: Vascular disorders affecting the arterial supply to the limbs.
  • Rheumatic heart disease: Myocardial and valvular damage resulting from rheumatic fever, attributed to Streptococcus pyogenes infection.
  • Congenital heart disease: Structural heart defects present from birth, disrupting normal cardiac development and function.
  • Deep vein thrombosis and pulmonary embolism: Venous thromboembolic events originating as thrombosis in the leg veins, which can embolize the pulmonary arteries.
  • Acute Left ventricular failure

In 2001, the American College of Cardiology/American Heart Association working group outlined four stages of heart failure:

  1. Stage A: Individuals at high risk of developing heart failure in the future, but without any current structural or functional heart disorders.
  2. Stage B: Presence of a structural heart disorder, such as left ventricular hypertrophy or previous myocardial infarction, but without any symptoms of heart failure at any stage.
  3. Stage C: Patients who have experienced current or previous symptoms of heart failure due to an underlying structural heart problem, and who are managed with medical treatment.
  4. Stage D: Advanced heart failure where patients require specialized, often hospital-based support, consideration for a heart transplant, or palliative care due to the severity of their condition.

These stages help categorize heart failure patients based on the presence of symptoms and the degree of structural heart disease, guiding appropriate management and interventions.

How the Normal Heart Works: The heart, a robust muscular pump slightly larger than a fist, is responsible for maintaining circulation by pumping adequate blood to all body parts.

Anatomy and Function

The heart comprises four chambers:

  • Atria: The two upper chambers, known individually as an atrium.
  • Ventricles: The two lower chambers.

Circulatory Pathway

  • Right Atrium: Receives deoxygenated blood from the systemic circulation and directs it to the right ventricle.
  • Right Ventricle: Pumps the deoxygenated blood to the lungs via the pulmonary artery for oxygenation.
  • Left Atrium: Receives oxygenated blood from the pulmonary veins.
  • Left Ventricle: Pumps the oxygen-rich blood into the systemic circulation through the aorta to supply the body’s tissues.

Coordination and Efficiency

The heart’s effectiveness hinges on the synchronised contraction of its four chambers. In a healthy state, the heart’s pumping capacity is more than sufficient to ensure adequate blood circulation throughout the body.

Pathophysiology describes the mechanisms leading to heart failure. When cardiac output is inadequate, the body compensates to maintain perfusion.

Compensatory Mechanisms

  • Chamber Dilation: The heart chambers may dilate to accommodate a larger volume of blood.
  • Myocardial Hypertrophy: The myocardium may thicken to enhance contractility. However, prolonged strain leads to myocardial cell death, weakening the heart muscle.
  • Neurohormonal Activation: The body releases hormones, such as norepinephrine and angiotensin II, which constrict blood vessels and signal the kidneys to retain sodium and water, increasing blood volume and pressure, exacerbating cardiac workload. This fluid accumulation results in congestion in tissues, known as congestive heart failure.

Progression to Heart Failure

As compensatory mechanisms fail, the heart’s ability to pump blood diminishes, leading to heart failure.

Heart Failure vs. Heart Attack

  • Heart Failure: A chronic condition where the heart gradually loses its ability to pump efficiently due to sustained overwork and damage.
  • Heart Attack (Myocardial Infarction): An acute event where a blood clot or atherosclerotic plaque obstructs coronary blood flow, causing ischemia and necrosis of myocardial tissue. Immediate intervention is required to restore perfusion.

In summary, heart failure is a progressive weakening of the heart’s pumping capacity, whereas a heart attack is a sudden obstruction of blood flow to the heart muscle.

Symptoms

    In heart failure, the myocardium fails to deliver sufficient blood to satisfy the body’s metabolic demands.Symptoms of heart failure may            manifest gradually or onset abruptly, including:

  • Dyspnea on exertion or orthopnea.
  • Fatigue and diminished energy levels.
  • Peripheral oedema, notably in the lower extremities.
  • Tachycardia or arrhythmias.
  • Exercise intolerance.
  • Wheezing.
  • Persistent cough, potentially producing white or pink sputum tinged with blood.
  • Abdominal distension (ascites).
  • Rapid weight gain due to fluid retention.
  • Anorexia and nausea.
  • Cognitive impairment or decreased alertness.
  • Angina, particularly if heart failure is secondary to myocardial infarction.

   When to Seek Medical Attention

    Consult a healthcare provider if you exhibit potential symptoms of heart failure. Immediate medical intervention (call 911 or emergency             services) is warranted for:

  • Chest pain.
  • Syncope or profound weakness.
  • Rapid or irregular heartbeat accompanied by dyspnea, chest pain, or syncope.
  • Sudden, severe dyspnea coupled with expectoration of white or pink frothy sputum.

   These symptoms may indicate heart failure, although differential diagnosis is essential due to the myriad of potential etiologies. Avoid             self-diagnosis.

   In an emergency, clinicians will conduct diagnostic evaluations to ascertain whether symptoms are attributable to heart failure or another       condition.

   Urgent Communication with Your Healthcare Provider: Immediate contact with your healthcare provider is necessary if you have                       established heart failure and:

  • There is an abrupt exacerbation of symptoms.
  • New symptoms develop.
  • You experience a rapid weight increase of 5 pounds (2.3 kilograms) or more within a few days.

    Such changes may signify worsening heart failure or insufficient therapeutic efficacy.

Heart Failure Diagnosis

    A. Medical History Assessment

       Your doctor will inquire about your medical history, focusing on the following aspects:

  • Underlying Conditions: Presence of coronary artery disease (CAD), diabetes, heart valve disease, or hypertension.
  • Lifestyle Habits: Smoking status, drug use, and alcohol consumption, including frequency and quantity.
  • Medication Usage: Current medications, including over-the-counter and prescription drugs.

    B. Symptom Review and Physical Examination

      Your doctor will evaluate your symptoms and perform a physical examination, which includes auscultating the heart and looking for                  clinical signs of heart failure. Additionally, they will check for other potential causes of myocardial weakness or stiffness.

    C. Diagnostic Tests

      To determine the cause and severity of heart failure, your doctor may order several tests, including:

  • Blood Tests: These assess renal and thyroid function, and lipid profiles, and check for anaemia (low red blood cell count).
  • B-type Natriuretic Peptide (BNP) Blood Test: Elevated BNP levels indicate decreased cardiac function.
  • Chest X-ray: This imaging technique evaluates heart size and detects fluid accumulation around the heart and lungs.
  • Echocardiogram: An ultrasound to visualise heart movement, structure, and functionality.
  • Electrocardiogram (EKG or ECG): This records the heart’s electrical activity.
  • Cardiac Catheterization: A procedure to assess heart function and determine if CAD is the cause of congestive heart failure.

     Stress Test: This evaluates heart performance and blood flow during exercise, aiding in the diagnosis of coronary artery disease.

Treatment option

Treatment for heart failure encompasses a variety of interventions aimed at managing symptoms, improving quality of life, and prolonging survival. Here are the key components of heart failure treatment:

Heart Failure Management Programs: Participating in a heart failure management program, often part of chronic disease management, is crucial. These programs involve a multidisciplinary team including heart failure nurses, cardiologists, pharmacists, physiotherapists, dietitians, and psychologists. They provide education on managing medications, recognizing symptom exacerbations, and monitoring fluid intake.

Cardiac Rehabilitation and Physical Activity: Cardiac rehabilitation combines exercise and education to promote heart health. Tailored exercise programs help improve strength, fitness, and confidence. Many programs now offer home-based options via telehealth.

Medications

Heart failure medications are essential for long-term management. These may include:

  • ACE Inhibitors or ARBs: Help relax blood vessels and reduce strain on the heart.
  • ARNIs: Manage blood pressure and fluid levels.
  • Beta Blockers: Lower heart rate, allowing the heart to pump more effectively.
  • MRAs: Prevent heart muscle damage and manage blood pressure.
  • SGLT2 Inhibitors: Reduce fluid retention and manage blood sugar in heart failure patients with diabetes.
  • Diuretics: Help eliminate excess fluid from the body, alleviating symptoms like swelling and shortness of breath.

Devices

For those with specific heart rhythm issues:

  • Pacemakers: Regulate heart rhythm and may include special types like CRT devices to synchronize heartbeats.
  • Implantable Cardioverter Defibrillators (ICDs): Monitor heart rhythm and deliver shocks if dangerous arrhythmias occur.

Surgery and Procedures

Surgical options for severe cases may include:

  • Catheter Ablation: Corrects abnormal heart rhythms by removing problematic heart tissue.
  • Heart Valve Surgery: Repairs or replaces damaged heart valves.
  • Coronary Artery Bypass Graft (CABG): Restores blood flow to the heart in cases of coronary artery disease.
  • Heart Transplant: Reserved for a select few with end-stage heart failure.

Each treatment approach is tailored to the individual’s specific condition, symptoms, and overall health, aiming to optimize heart function and improve quality of life.

 

Prevention of Congestive Heart Failure

While some risk factors for congestive heart failure (CHF) such as age, family history, and race are beyond control, there are several lifestyle changes and medical strategies you can adopt to reduce your risk:

Lifestyle Modifications:

  1. Maintain a Healthy Weight: Achieve and sustain a weight that is appropriate for your body type and height. This helps reduce strain on the heart.
  2. Heart-Healthy Diet: Consume a balanced diet rich in fruits, vegetables, whole grains, lean proteins, and low-fat dairy products. Limit saturated fats, trans fats, cholesterol, sodium, and added sugars.
  3. Regular Exercise: Engage in moderate-intensity aerobic exercise most days of the week. Physical activity strengthens the heart and improves overall cardiovascular health.
  4. Stress Management: Practice stress-relieving techniques such as deep breathing, meditation, yoga, or hobbies to lower stress levels, which can impact heart health.
  5. Avoid Tobacco: Quit smoking and avoid secondhand smoke. Smoking damages the heart and blood vessels, increasing the risk of heart disease.
  6. Limit Alcohol and Avoid Recreational Drugs: Moderate or eliminate alcohol consumption. Avoid recreational drugs, which can harm the heart and contribute to heart failure.

Medical Management:

  1. Manage Medical Conditions: Treat and control conditions such as hypertension, diabetes, and high cholesterol as these contribute to cardiovascular disease risk.