Apical 4-chamber echocardiogram of the left ventricle without and with ultrasound enhancing agent

The 4-chamber view of the LV is initially obtained by imaging at the fundamental (interrogating) frequency (panel A). The same image after administration of UEA (panel B). Note that the endocardial border is identified. Harmonic imaging at 7 MHz following echocardiographic contrast administration (panel C) demonstrates considerable improvement in the contrast effect, identifying the LV cavity outline with greater confidence.