These chest X rays show a dilated ascending aorta.  
	
The PA view demonstrates dilatation of the ascending portion of the 
aorta as evidenced by a prominent bulge in the right mediastinal shadow.  Note that the heart size is normal, as reflected by a 
 cardiothoracic ratio  less than 50%.
	  
	   
The lateral view shows a 
dilated ascending aorta  as evidenced by the shadow anterosuperior to the heart.