Heart failure is a prevalent cause of hospital readmissions.
Understanding the causes, exacerbating factors, and treatment protocols is vital for effective patient management and reducing hospital visits.
Definition of Heart Failure
Heart Failure: A condition resulting from structural or functional cardiac disorders, leading to the heart's inability to pump adequately to meet metabolic demands.
Causes of Heart Failure
Several underlying medical conditions can lead to heart failure:
Coronary Artery Disease: Blood flow to the heart muscle is reduced, causing ischemia.
Myocardial Infarction (MI): Also known as a heart attack; damage to heart muscle from reduced blood supply.
Hypertension: Chronic high blood pressure can lead to heart failure by causing the heart to work harder.
Cardiomyopathy: Diseases of the heart muscle that affect its size, shape, and ability to function.
Valvular Disorders: Malfunction of heart valves can disrupt normal blood flow within the heart.
Kidney Dysfunction: Impaired kidney function can result in fluid overload, affecting heart performance.
Initial Body Response
Initially, the body compensates for heart failure triggers by increasing cardiac output.
Progression of Heart Failure
Over time, the heart becomes fatigued, alters its shape, and fails to function properly.
Diagnostic Tests for Heart Failure
Echocardiogram: Measures ejection fraction (EF), a key indicator of heart function.
Normal EF in individuals without heart failure: 55% - 65%.
Electrocardiogram (ECG): Evaluates the electrical activity and potential abnormalities of the heart.
Brain Natriuretic Peptide (BNP) Blood Test: A BNP level greater than 100 pg/mL suggests heart failure.
Types of Heart Failure
1. Systolic Heart Failure (Heart Failure with Reduced Ejection Fraction)
Characterized by a reduced ejection fraction, specifically:
EF less than 40% indicates decreased cardiac output and pump failure.
Leads to fluid overload due to inadequate blood being ejected from the left ventricle.
2. Diastolic Heart Failure (Heart Failure with Preserved Ejection Fraction)
Characterized by:
EF remains above 50% despite impaired filling due to stiff ventricles.
Heart works harder as it cannot relax enough for proper filling.
Symptoms of Heart Failure
Common symptoms include:
Dyspnea: Difficulty breathing, especially upon exertion or when lying down.
Fatigue: Unusual tiredness during daily activities.
Fluid Retention: Leads to swelling in various parts of the body.
Left-Sided Heart Failure
If the left side of the heart is affected:
Blood backs up into the lungs.
Symptoms include:
Crackles upon auscultation.
Difficulty breathing (orthopnea or paroxysmal nocturnal dyspnea).
Mnemonic: Think "Left side, lungs affected".
Right-Sided Heart Failure (Cor Pulmonale)
If the right side is affected:
Blood backs up into the systemic circulation.
Symptoms include:
Enlarged liver and spleen (hepatosplenomegaly).
Ascites: Fluid accumulation in the abdominal cavity.
Jugular vein distension.
Dependent edema: Swelling in the lower extremities.
Mnemonic: Think "Right side, rest of the body is affected".
Staging of Heart Failure
Heart failure is staged based on symptom severity, typically categorizing from mild to end-stage.
Treatment Protocols for Heart Failure
Key medications include:
Angiotensin Receptor Blockers (ARBs): Help to relax blood vessels, reducing heart workload.
Beta Blockers: Improve symptoms and extend survival by slowing heart rate and reducing blood pressure.
Diuretics: Help reduce fluid overload and improve symptoms, but may not necessarily extend survival.
Digoxin Monitoring
Patients prescribed Digoxin must be monitored for toxicity.