What are the diagnostic criteria for heart failure?

Heart Failure Diagnostic Criteria

Heart failure diagnosis requires the presence of typical symptoms (dyspnea, fatigue, or peripheral edema) PLUS objective evidence of cardiac dysfunction on echocardiography, with elevated natriuretic peptides or evidence of congestion providing additional diagnostic support. 1, 2

Core Diagnostic Requirements

The diagnosis of heart failure mandates three essential components 3, 1, 4:

• Typical symptoms including dyspnea, fatigue, and peripheral edema (though these lack specificity) 1
• Objective evidence of cardiac dysfunction at rest, typically demonstrated by echocardiography with Doppler 1, 4
• In doubtful cases, a favorable response to heart failure therapy supports the diagnosis 4

Initial Clinical Assessment

History and Physical Examination

Specific elements to evaluate include 1, 5:

• Volume status assessment: jugular venous distension, hepatojugular reflux, peripheral edema, pulmonary rales, and S3 gallop 5
• Orthostatic blood pressure changes to evaluate volume status 5
• Weight, height, and BMI calculation as baseline monitoring parameters 1, 5
• Detailed substance exposure history: alcohol consumption, illicit drugs, chemotherapy agents, and alternative therapies 1, 5

Critical pitfall: A displaced cardiac apex and third heart sound are highly specific physical findings when present, but their absence does not exclude heart failure 6

Essential Diagnostic Tests

Mandatory Initial Testing

Echocardiography with Doppler is the cornerstone diagnostic test that provides objective evidence of cardiac dysfunction and measures left ventricular ejection fraction (LVEF) 1, 5. This test is non-negotiable and should not be delayed 5.

12-lead ECG must be performed in all patients, as a completely normal ECG makes heart failure highly unlikely (negative predictive value >90%) 3, 1, 5.

Chest X-ray (PA and lateral views) should be obtained to detect cardiomegaly, pulmonary venous congestion, interstitial edema, pleural effusions, and Kerley B lines 3, 1, 5.

Laboratory Testing

The following tests are recommended for initial evaluation 3, 1:

• Complete blood count and hemoglobin 3
• Serum electrolytes (sodium, potassium), blood urea nitrogen, creatinine with estimated GFR 3, 1
• Liver function tests (bilirubin, AST, ALT, GGTP) 3
• Fasting glucose and HbA1c 3
• Thyroid-stimulating hormone 3, 1
• Lipid profile 1
• Ferritin and transferrin saturation 3

Natriuretic Peptides

BNP or NT-proBNP should be measured when clinical diagnosis remains uncertain after initial evaluation 3, 1, 5. These biomarkers have high negative predictive value, making them particularly valuable as "rule out" tests 1. The 2021 universal definition emphasizes elevated natriuretic peptides as corroborative evidence of heart failure 2.

Classification by Ejection Fraction

Once heart failure is confirmed, classification by LVEF is essential 1, 2:

• HFrEF (Heart Failure with Reduced EF): LVEF ≤40% 2 or <45-50% 1
• HFmrEF (Heart Failure with Mildly Reduced EF): LVEF 41-49% 2
• HFpEF (Heart Failure with Preserved EF): LVEF ≥50% 2 or ≥45-50% with evidence of diastolic dysfunction 1
• HFimpEF (Heart Failure with Improved EF): baseline LVEF ≤40%, ≥10 point increase, and second measurement >40% 2

For HFpEF diagnosis, diastolic dysfunction must be demonstrated through E/A ratio, E/Ea ratio, deceleration time, and pulmonary vein flow 1.

Additional Testing in Selected Cases

Coronary Artery Disease Evaluation

Invasive coronary angiography is recommended for 3, 1, 5:

• Patients with angina or significant ischemia who are suitable for revascularization 3
• Patients with chest pain of uncertain origin 1
• Intermediate to high pre-test probability of CAD with ischemia on non-invasive testing 3

Cardiac CT may be considered in patients with low to intermediate pre-test probability of CAD to rule out coronary stenosis 3.

Exercise Testing

Exercise testing has limited diagnostic value but is useful for 3, 1:

• Mandatory: evaluation for heart transplantation or mechanical circulatory support (cardiopulmonary exercise testing) 3
• Excluding heart failure as the cause of dyspnea 3, 1
• Prognostic stratification 1

Specialized Testing

Consider when clinically indicated 1, 5:

• Hemochromatosis screening in appropriate clinical context 1, 5
• HIV testing when risk factors present 1, 5
• Rheumatologic panel if systemic disease suspected 1, 5
• Sleep study for suspected sleep-disordered breathing 1
• Endomyocardial biopsy in highly selected cases 5

Diagnostic Algorithm

The ESC guidelines provide a structured approach 1:

1. Evaluate for typical symptoms and signs
2. Perform initial tests (ECG, chest X-ray, basic labs)
3. Measure natriuretic peptides if clinical suspicion remains
4. Confirm diagnosis with echocardiography
5. Determine if systolic or diastolic dysfunction
6. Identify underlying etiology (especially coronary artery disease)
7. Classify severity using NYHA functional classification

Important caveat: There is often poor correlation between symptom severity and the degree of cardiac dysfunction, so objective testing cannot be bypassed based on symptom assessment alone 1.