Left-Sided Heart Failure

• Heart failure is a clinical syndrome where the heart cannot pump enough blood to meet the body's needs
• It can result from structural or functional cardiac disorders that impair the ability of the ventricle to fill with or eject blood

Left-Sided Heart Failure

• Left-sided heart failure occurs when the left ventricle cannot effectively pump blood out to the body
• This leads to a backup of blood into the left atrium and pulmonary veins, causing pulmonary congestion

Causes of Left-Sided Heart Failure

• Ischemic heart disease: Reduced blood supply to the heart muscle weakens the left ventricle
• Hypertension: Chronic high blood pressure increases the workload on the left ventricle, leading to hypertrophy and eventual failure
• Valvular heart disease: Conditions like aortic stenosis or mitral regurgitation can impair the left ventricle's ability to pump blood effectively
• Cardiomyopathy: Diseases affecting the heart muscle directly, such as dilated cardiomyopathy
• Myocarditis: Inflammation of the heart muscle, often due to viral infections

Types of Left-Sided Heart Failure

• Heart failure with reduced ejection fraction (HFrEF): The left ventricle cannot contract forcefully enough, resulting in a reduced ejection fraction (typically ≤ 40%)
  • Also known as systolic heart failure
• Heart failure with preserved ejection fraction (HFpEF): The left ventricle can contract normally, but it is stiff and cannot relax properly, impairing filling
  • Also known as diastolic heart failure
  • Ejection fraction is typically ≥ 50%
• Heart failure with mid-range ejection fraction (HFmrEF): Ejection fraction is in the range of 41-49%
  • Characteristics and treatment strategies are intermediate between HFrEF and HFpEF

Symptoms of Left-Sided Heart Failure

• Dyspnea: Shortness of breath, especially during exertion or when lying down (orthopnea)
• Cough: May be dry or produce frothy, blood-tinged sputum
• Pulmonary edema: Fluid accumulation in the lungs, leading to severe respiratory distress
• Fatigue: Due to reduced blood flow to the body
• Exercise intolerance: Inability to perform physical activities due to shortness of breath and fatigue
• Paroxysmal nocturnal dyspnea: Sudden shortness of breath at night that awakens the person, relieved by sitting or standing

Diagnosis of Left-Sided Heart Failure

• Physical examination: Findings such as crackles in the lungs, an enlarged heart, and a rapid heart rate
• Echocardiography: Assesses the structure and function of the heart, including ejection fraction
• Electrocardiogram (ECG): Can identify arrhythmias and signs of previous heart attacks
• Chest X-ray: Reveals pulmonary congestion and heart enlargement
• BNP (B-type natriuretic peptide) blood test: Elevated levels indicate heart failure

Treatment of Left-Sided Heart Failure

• Lifestyle modifications: Low-sodium diet, fluid restriction, regular exercise, and smoking cessation
• Medications:
  • ACE inhibitors or ARBs: Relax blood vessels and lower blood pressure
  • Beta-blockers: Slow heart rate and lower blood pressure
  • Diuretics: Reduce fluid retention
  • Digoxin: Increases the strength of heart muscle contractions
  • ARNI (angiotensin receptor-neprilysin inhibitor): Alternative to ACE inhibitors or ARBs in select patients
  • SGLT2 inhibitors: Originally for diabetes: Shown to reduce mortality in heart failure patients
• Medical devices:
  • Implantable cardioverter-defibrillator (ICD): Prevents sudden cardiac death
  • Cardiac resynchronization therapy (CRT): Coordinates the contractions of the left and right ventricles

Right-Sided Heart Failure

• Right-sided heart failure occurs when the right ventricle cannot effectively pump blood into the pulmonary artery
• This leads to a backup of blood into the right atrium and systemic circulation, causing systemic congestion

Causes of Right-Sided Heart Failure

• Left-sided heart failure: Most common cause; increased pressure in the pulmonary vessels due to left-sided heart failure strains the right ventricle
• Pulmonary hypertension: High blood pressure in the pulmonary arteries increases the workload on the right ventricle
• Lung diseases: Conditions like COPD and pulmonary embolism can lead to pulmonary hypertension and right-sided heart failure
• Valvular heart disease: Tricuspid or pulmonic valve stenosis or regurgitation
• Congenital heart defects: Certain birth defects can strain the right ventricle

Symptoms of Right-Sided Heart Failure

• Peripheral edema: Swelling in the ankles and legs
• Ascites: Fluid accumulation in the abdomen
• Hepatomegaly: Enlargement of the liver
• Jugular venous distension (JVD): Increased pressure in the jugular veins
• Fatigue: Due to reduced blood flow to the body
• Nocturia: Frequent urination at night

Diagnosis of Right-Sided Heart Failure

• Physical examination: Findings such as peripheral edema, ascites, hepatomegaly, and JVD
• Echocardiography: Assesses the structure and function of the right ventricle
• Right heart catheterization: Measures pressures in the right heart and pulmonary artery
• BNP blood test: Elevated levels indicate heart failure
• Liver function tests: May be abnormal due to liver congestion

Treatment of Right-Sided Heart Failure

• Treatment of underlying cause: Addressing the primary cause, such as left-sided heart failure or pulmonary hypertension
• Lifestyle modifications: Low-sodium diet, fluid restriction, and regular exercise
• Medications:
  • Diuretics: Reduce fluid retention
  • Vasodilators: Relax blood vessels and lower blood pressure
  • Oxygen therapy: If pulmonary hypertension is present
• In severe cases, a heart transplant may be considered

Combined Left- and Right-Sided Heart Failure

• Patients can experience both left- and right-sided heart failure simultaneously
• Symptoms of both left- and right-sided heart failure will be present
• Management involves addressing the symptoms and underlying causes of both conditions