Left ventricular anatomy: its nomenclature, segmentation, and planes of imaging

The American Heart Association recommends a model of the left ventricular myocardium based on 17 segments. The model is accepted and used by imagers in nuclear medicine, echocardiography, magnetic resonance imaging, and, more recently, in computed tomography. Some problems persist with the orientation and presentation of the planar imaging views between the modalities and with their registration with the segmental model. These problems would be eased if the "anterior" wall were to be called the superior wall, which is attitudinally correct. It would follow that the "anterior descending" and "posterior descending" arteries would be known as the superior and inferior interventricular arteries. This is also more correct anatomically, as is the need to describe the papillary muscles of the mitral valve as being positioned superiorly and inferiorly. In this review, we discuss these currently existing problems and make a plea for more stringent description and display of the planes used in imaging.