Initial experience using contrast enhanced real-time three-dimensional exercise stress echocardiography in a low-risk population

Abstract

Although emerging data support the utility of real-time three-dimensional echocardiography (RT3DE) during dobutamine stress testing, the feasibility of performing contrast enhanced RT3DE during exercise treadmill stress has not been explored. Two-dimensional (2D) and three-dimensional (3D) acquisition were performed in 39 patients at rest and peak exercise. Contrast was used in 29 patients (74%). Reconstruction was performed manually by generating short axis cut planes at the base, mid-ventricle and apex, and automatically by generating 9 short axis slices. Three-dimensional acquisition was feasible during rest and stress regardless of the use of contrast. Time to acquire stress images was reduced using 3D (35.2±17.9 s) as compared to 2D acquisition (51.6±14.7 s; P<0.05). Using a 17-segment model, of all 663 segments, 588 resting (88.6%) and 563 stress segments (84.9%) were adequately visualized using manually reconstructed 3D data, compared with 618 resting (93.2%) and 606 stress segments (91.4%) using 2D data (P rest=0.06; P stress=0.07). We concluded that contrast enhanced RT3DE is feasible during treadmill stress echocardiography.

Keywords: three-dimensional exercise stress echocardiography..

Figure 1

Three-dimensional demonstration of normal wall motion response in a single patient to exercise stress using manual reconstruction. (A) Baseline non-contrast cropped short axis images from base (left) to apex (right), at end diastole (ED, top) and end systole (ES, bottom). (B) Cropped short axis images at peak exercise stress in equivalent slices. Note smaller left ventricular cavity size.

Figure 2

Three-dimensional representation using iSlice software for the same patient as in Figure 1. (A) Rest images, with cropped planes automatically cut. (B) Rest images, automatically cropped.

Figure 3

Three-dimensional representation of ischemia in the anteroseptal distribution using manual reconstruction. (A) Baseline cropped short axis images from base (left) to apex (right), at end diastole (ED) and end systole (ES). (B) Cropped short axis images at peak exercise stress in equivalent slices. Note left ventricular cavity as ES was larger at peak stress. In addition, there is lack of thickening in the anteroseptal distribution (arrowheads), suggestive of ischemia.