The role of echocardiographic harmonic imaging and contrast enhancement for improvement of endocardial border delineation

Despite advances in imaging technology, many myocardial segments remain poo rly visualized with echocardiography; however, both contrast enhancement an d harmonic imaging have shown promise for improving endocardial definition. Fifty subjects with technically Limited echocardiograms were studied with fundamental and harmonic imaging as well as during echocardiographic contra st injection. Overall endocardial visualization scores improved with both t echniques compared with fundamental imaging. Harmonic imaging improved endo cardial visualization in 43% of all segments and in 57% of segments nonvisu alized with fundamental imaging. The benefit of harmonic imaging was seen i n all segments. Contrast echocardiography had similar overall improvements in visualization (42% of all segments, 67% of segments nonvisualized with f undamental imaging) but was not helpful. in all regions. Harmonic imaging o utperformed contrast in 9 of 22 segments, whereas contrast was superior in 4 of 22. In a subgroup of patients with very poor images, contrast enhancem ent was superior, with a greater increase in overall score and a higher sal vage rate than harmonic (68% vs 40%).