Real-time 3-D ultrasound acquisition and display for cardiac volume and ejection fraction evaluation

The objective of this study was to test if three-dimensional (3-D) ultrasou nd (US) provides accurate determination of the cardiac volumes and ejection fraction. The 3-D device (Model l-Volumetrics,) is a 3-D acquisition syste m using a 2-Mhz matrix probe that insonates the whole cardiac volume in a Q -chamber view and collects the entire backscattered US echoes from this vol ume within one cardiac cycle. The complete 3-D US information stored in the memory can then be cut into 2-D views of any arbitrary orientation. For vo lume determination, the best 4-chamber view was selected into the memory, t hen 6 transverse views were displayed at different depths along the ventric le long axis, and the contour of the ventricle was drawn on each of these v iews. The left ventricle volume in diastole (LVDV) and the ejection fractio n (EF) obtained by 3-D US were compared with those from x-ray and isotopic angiographies, and 2-D echo-time motion (2-D Echo-TM). The variations in st roke volume (SV) during a stand test, measured by 3-D US, and aortic Dopple r were compared. The correlation between EF evaluated from 3-D US and x-ray or isotopic angiographies was found to be good (r = 0.80 p < 0.001; 0.86 p < 0.001), but lower with 2-D Echo-TM (r = 0.59 p < 0.001). For LVDV, the c orrelation was acceptable with x-ray angiography (r = 0.75 p < 0.001), but much lower with isotopic angiography and 2-D Echo-TM (r 0.47 p < 0.001; r = 0.55 p < 0.001). A good correlation was also found between the SV changes measured by 3-D US and aortic Doppler (r = 0.79 p < 0.001). (C) 2000 World Federation for Ultrasound in Medicine & Biology.