Harmonic imaging with Levovist for transthoracic echocardiographic reconstruction of left ventricle in patients with post-ischemic left ventricular dysfunction and suboptimal acoustic windows

Background: Attempts to perform transthoracic 3-dimensional echocardiography (3DE) are often encumbered by poor definition of chamber borders in adult patients who have technically suboptimal acoustic windows. Methods: To assess whether harmonic imaging (HI) and contrast agents can facilitate transthoracic 3DE assessment of the left ventricle, we used fundamental imaging (FI), HI alone, and HI coupled with the echo-enhancing contrast agent Levovist in 15 consecutive patients with post-ischemic left ventricular (LV) dysfunction and technically difficult windows. Dynamic 3DE image data sets were obtained at 5-degree angles (36 slices) from a transthoracic apical view. From these data a total of 240 myocardial segments were analyzed with the use of dynamic short-axis paraplane slices at basal, middle, and apical LV levels (standard 16 segment model). For border definition, each segment was scored in random sequence on the following scale by 2 independent investigators: 0 = not seen, 1 = suboptimal visualization, and 2 = well defined. Results: Our results showed a significant increase in the number of well-visualized segments when harmonic mode combined with Levovist injection was compared with FI and HI alone. Conclusion: Harmonic imaging alone improves LV assessment by 3DE when compared with FI. Contrast imaging in which Levovist is added to HI further improves the capability of transthoracic tomographic 3DE in the visualization of LV myocardial segments. This could allow 3DE by transthoracic windows to be used more widely in adults for the evaluation of LV volume and function.