Chest XRay in Congenital Heart Disease

1. See Also
   1. Congenital Heart Disease
2. Causes: Increased pulmonary vasculature (edematous, white lung fields)
   1. Cyanotic heart disease (mixed oxygenated and deoxygenated blood)
      1. Total Anomalous Pulmonary Venous Return
      2. Truncus Arteriosus
      3. Transposition of the Great Vessels
   2. Noncyanotic heart disease (right-to-left shunt)
      1. Atrial Septal Defect
      2. Ventricular Septal Defect
      3. Patent Ductus Arteriosus
3. Causes: Decreased pulmonary vasculature (clear or black lung fields)
   1. Cyanotic heart disease
      1. Tetralogy of Fallot
      2. Ebstein Anomaly
      3. Hypoplastic Left Heart Syndrome
   2. Noncyanotic heart disease (left-sided obstruction)
      1. Aortic Stenosis
      2. Pulmonary stenosis
      3. Aortic Coarctation
4. Causes: Classic heart appearances on xray
   1. Tetralogy of Fallot
      1. Boot-shaped heart
   2. Total Anomalous Pulmonary Venous Return (TAPVR)
      1. Snowman or Figure-of-eight sign
   3. Transposition of Great Vessels
      1. Egg on a string sign
   4. Aortic Coarctation
      1. Three sign (aortic knob prominent, with distal aortic dilitation)
5. Causes: Normal heart size despite Congenital Heart Disease
   1. Tricuspid atresia
   2. Pulmonary atresia
   3. Pulmonic stenosis
   4. Tetralogy of Fallot
6. Calculation: Cardiothoracic Index
   1. Calculates whether heart diameter is more than half (roughly) the chest cavity width
   2. Measurements
      1. Transverse diameter of the heart on AP Chest XRay
      2. Thoracic cavity width on AP Chest XRay
   3. Calculation
      1. Index = (heart diameter) / (thoracic width)
   4. Interpretation
      1. Index >0.6 is consistent with cardiomegaly
7. References
   1. Civitarese and Crane (2016) Crit Dec Emerg Med 30(1): 14-23
   2. Fuchs and Yamamoto (2012) APLS, Jones and Bartlett, Burlington, 135-7