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What is Lt border of the heart in CXR is formed by – a) Pulmonary arteryb) Pulmonary  veinc) Abdominal aortad) Arch of aortae) Rt ventricles and explain in detail?
The left margin of heart is formed by aortic knuckle (prominence due to aortic arch), pulmonary trunk, left auricle, and left ventricle.