NATIVE TISSUE HARMONIC IMAGING IMPROVES ENDOCARDIAL BORDER DEFINITIONAND VISUALIZATION OF CARDIAC STRUCTURES

Background. The purpose of this study was to examine the impact of nat ive tissue harmonic imaging on endocardial border definition, wall mot ion scoring, and visualization of intracardiac structures. Methods and Results. For wall motion analysis, 60 consecutive patients underwent standard transthoracic echocardiograms in both harmonic and fundamenta l modes. Three experienced echocardiographers reviewed each echocardio gram. Endocardial border definition for each wall segment was graded f rom 1 to 4 (l = excellent endocardial definition). Wall motion was sco red by using a standard 16-segment model and 1 to 5 scale. For visuali zation of cardiac structures, 50 consecutive patients were studied. Tw o experienced interpreters reviewed each echocardiogram for both norma l and abnormal structures by using the following scoring scale: (1) ha rmonic is much better than fundamental, (2) harmonic is slightly bette r than fundamental, (3) harmonic and fundamental are equivalent, (4) f undamental is slightly better than harmonic, and (5) fundamental is mu ch better than harmonic. Visualization of 64% (95% confidence interval [CI] 0.61 to 0.66) of all segments improved in harmonic mode, with 26 % (95% CI 0.24 to 0.29) improving from poor/not seen to good/excellent . Of 444 segments deemed poor/not seen, visualization of 312 (70%) (95 % CI 0.66 to 0.75) improved to good/excellent with harmonic mode. Of t hese 312 segments, 55% comprised the lateral and anterior walls on api cal views. Interobserver agreement on endocardial border definition wa s 82% to 86%. Scoring of wall motion was altered in 171 of 1075 (16%) of segments by harmonic mode. This was significantly greater than the interobserver disagreement, which was only 10% (p < 0.002). Mitral val ve chordae and papillary muscles were visualized slightly/much better with harmonic mode in 40 of 50 echocardiograms. Left atrial boundaries were seen slightly/much better in harmonic mode in 29 of 50 studies. Abnormal structures were seen slightly/much better in harmonic mode in 12 of 14 cases. Conclusions. Native tissue harmonic imaging has signi ficant impact on endocardial border definition and wall motion scoring and improves the visualization of both normal and abnormal cardiac st ructures.