These chest X rays show a dilated pulmonary trunk and  normal vascularity. 
			
			In this PA view, the 
 dilated pulmonary trunk  is demonstrated by the convex density below the aortic knob.
	  
	  	Note also that there is dilation of the left pulmonary artery, but that the remainder of the pulmonary arterial markings is normal. Heart size is also normal. These chest X rays are consistent with pulmonary valve stenosis.