Fig. 2

a Guide for adjusting imaging planes from the CT standard planes to the standard cardiac planes [i.e., short axis (white line), orthographic long axis (blue lines), and horizontal long axis view (orange lines)]. b Guide for adjusting imaging planes from the standard cardiac planes to the “three- and four-chamber view.” The four-chamber view is achieved by adjusting a perpendicular plane to the short axis crossing the middle of the mitral valve and the acute margin (white line). The three-chamber view is achieved by adjusting a perpendicular plane to the short axis crossing the middle of the mitral valve and the middle of the aortic valve (blue line)