<prompt> All of the following are true in chest X ray PA view EXCEPT:Right ventricle forms the right heart borderLeft ventricle forms the left heart borderCardiothoracic ratio in adults is normally 50 or less than thatRight atrium forms the right heart border  <response>: Ans. a Right ventricle forms the right heart borderRef: Essential radiology 2nd ed. 122 Right ventricle is not a border forming structure in PA view. However, it forms anterior border in lateral view of Chest X-Ray. 