Nadas' Criteria for Clinical Diagnosis of Heart Disease
Overview and Utility
- Clinical assessment tool determining presence of heart disease.
- Diagnostic threshold: ONE major criterion OR TWO minor criteria.
- Limitation: Reduced utility in newborns due to subtle clinical signs.
Diagnostic Categories
Major Criteria
- Systolic murmur grade III or more: Indicates significant abnormality. Pansystolic murmurs always abnormal regardless of intensity.
- Diastolic murmur: Almost always indicates organic heart disease.
- Central cyanosis: Suggests right-to-left shunt or inadequate pulmonary oxygenation.
- Congestive cardiac failure: Strongly indicates heart disease. Exclude extracardiac causes (anemia, hypoglycemia) in neonates and infants.
Minor Criteria
- Systolic murmur grade I or II: Soft murmurs do not exclude heart disease.
- Abnormal second heart sound: Highly subjective but extremely useful bedside tool for classifying heart disease.
- Abnormal electrocardiogram (ECG): Determines axis, hypertrophy, or conduction issues.
- Abnormal chest X-ray: True cardiomegaly on inspiratory film suggests heart disease. Caution: Normal thymus mimics cardiomegaly in children under two years.
- Abnormal blood pressure: Aids in identifying specific hemodynamic anomalies.
Summary Table
| Major Criteria | Minor Criteria |
|---|---|
| Systolic murmur grade III or more | Systolic murmur grade I or II |
| Diastolic murmur | Abnormal second heart sound |
| Cyanosis | Abnormal electrocardiogram |
| Congestive cardiac failure | Abnormal X-ray |
| Abnormal blood pressure |