The purpose of this study was to compare fundamental ultrasound imaging to harmonic imaging (without contrast) for the detection of systolic endocardial visualization (EV). Harmonic ultrasound imaging has been primarily used with various intravenous contrast agents to improve the resolution of cardiac structures by decreasing background clutter and improving the signal-to-noise ratio in contrasted cardiac images. Whether its use without contrast is better for detecting endocardial wall motion than fundamental ultrasound imaging is not well known. Twenty-six patients (18 males and 8 females, mean age 55 years) were selected at random and imaged using fundamental and harmonic modes. Parasternal long and short axis, apical 4 and 2 chamber views were obtained in all patients. Two observers independently graded EV for 22 segments in all patients using a 3-point scale (0: endocardium not seen, 1: seen in part but not all the segment, 2: endocardium seen along entire segment). Each imaging mode was graded separately. The segment scores for each patient were summated and averaged. The mean segment score ± standard deviation was obtained in observer one and two for fundamental and harmonic imaging. The score of observer one for fundamental vs harmonics was 1.2 ± 0.8 vs 1.6 ± 0.7 (p < 0.001), and for observer two 1.1 ± 0.8 vs 1.4 ± 0.8 (p < 0.001). The correlations (r) between the observer scoring for each imaging technique were 0.7 and 0.69 for fundamental and harmonic respectively, p < 0.001). The percent total EV scores for fundamental and harmonic imaging were higher in the parasternal views compared to the apical views, (72 and 90% vs 51 and 71% for observer one; 72 and 82% vs 44 and 61% for observer two.) However, the percent change was higher with harmonic mode in the apical views compared to the parasternal views, 39 vs 28% for observer one and 39 vs 28% for observer two, p < 0.001. Harmonic imaging can be used without contrast to optimally visualize the endocardium. Harmonic imaging improves the systolic EV to a greater degree in the apical views compared to the parasternal views. Finally, harmonic echocardiographic imaging without contrast improves visualization of the endocardium compared to fundamental ultrasound imaging.
|Original language||English (US)|
|Number of pages||6|
|State||Published - Dec 1 1998|
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging
- Cardiology and Cardiovascular Medicine