The Human Heart AL: antero-lateral wall; IVS: inferior interventricular septum; LA: Left Atrium; LV: Left Ventricle; MV: mitral valve; RA: Right Atrium; RV: Right Ventricle. Arrow points at diaphragm. In this cycle (the scan plane been modified by respiration) the postero-lateral (and not the antero-lateral) wall of the left ventricle is seen.