Signs and Symptoms of Left-Sided Heart Failure
The most common signs and symptoms of left-sided heart failure include dyspnea (especially with exertion), orthopnea, paroxysmal nocturnal dyspnea, fatigue, and pulmonary congestion. 1
Respiratory Symptoms
- Dyspnea (shortness of breath) is a cardinal symptom that may occur at rest, during exertion, or when lying flat (orthopnea) 1
- Paroxysmal nocturnal dyspnea - episodes of severe shortness of breath that wake patients from sleep 1
- Cough, especially when lying down, often due to pulmonary congestion 1
- Pulmonary rales/crackles on auscultation due to fluid accumulation in the lungs 2
- Upper lung zone flow redistribution, interstitial or alveolar edema, and bilateral pleural effusions on chest radiography 2
Cardiovascular Signs
- S3 gallop (third heart sound) - highly specific for ventricular dysfunction 3
- Displaced cardiac apex due to left ventricular enlargement 3
- Pulmonary congestion resulting from elevated left atrial and pulmonary venous pressures 2
- Tachycardia as a compensatory mechanism to maintain cardiac output 2
- Cardiomegaly visible on chest radiography 1
Systemic Manifestations
- Fatigue and decreased exercise tolerance due to reduced cardiac output and skeletal muscle perfusion 1
- Peripheral edema, particularly ankle swelling, resulting from fluid retention 1
- Nocturia (frequent urination at night) due to improved renal perfusion when lying down 1
- Weight gain from fluid retention 1
- Poor appetite and early satiety 1
Advanced Signs
- Cheyne-Stokes respiration (periodic breathing pattern) in severe cases 2
- Cachexia (muscle wasting) in chronic advanced heart failure 4
- Confusion or altered mental status due to decreased cerebral perfusion 4
- Oliguria (reduced urine output) from decreased renal perfusion 4
Pathophysiological Basis
- Left ventricular dysfunction leads to increased left ventricular filling pressures 2
- Elevated left atrial pressure causes pulmonary venous congestion 2
- Reduced cardiac output results in neurohormonal activation (sympathetic nervous system, renin-angiotensin-aldosterone system) 5
- Cardiac remodeling with chamber dilation and/or hypertrophy occurs as the disease progresses 2
Diagnostic Considerations
- Symptoms alone are insufficient for diagnosis - objective evidence of cardiac dysfunction is required 1
- Echocardiography is the diagnostic standard to confirm left ventricular dysfunction 3
- Elevated B-type natriuretic peptide (BNP) or NT-proBNP levels support the diagnosis 1
- A normal electrocardiogram has high negative predictive value for excluding left ventricular systolic dysfunction 1
Clinical Pearls
- The severity of symptoms may not correlate with the degree of cardiac dysfunction - patients with preserved ejection fraction may have severe symptoms while those with reduced ejection fraction may be relatively asymptomatic 1
- Left-sided heart failure often progresses to biventricular failure with additional right-sided signs (jugular venous distention, hepatomegaly, ascites) 4
- Acute decompensation may be precipitated by medication non-compliance, dietary indiscretion, acute coronary syndromes, arrhythmias, infections, or uncontrolled hypertension 2
Remember that heart failure is a clinical syndrome requiring both symptoms and objective evidence of cardiac dysfunction for diagnosis, and the underlying cause should always be identified 1, 6.