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What is Which of the congenital cardiac anomaly give rise to characteristic 'snowman appearance' on chest x-ray? and explain in detail?
With the unobstructed types of total anomalous pulmonary venous connection (TAPVC), the hea is enlarged with increased pulmonary flow. Pulmonary edema is uncommon. In patients with return to the left innominate vein, there may be a characteristic bulging of the superior mediastinum bilaterally, producing a "snowman," or figure-eight, contour. With obstructed types, the hea size is nearly normal; there is very marked pulmonary edema, which may give a granular appearance to the lungs, making differentiation from respiratory distress syndrome difficult in a newborn. Ref: Brown D.W., Fulton D.R. (2011). Chapter 83. Congenital Hea Disease in Children and Adolescents. In V. Fuster, R.A. Walsh, R.A. Harrington (Eds), Hurst's The Hea, 13e.