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Objectives: Dobutamine stress echocardiography (DSE) and contrast-enhanced electron beam tomography (EBCT) both have the potential to noninvasively detect coronary artery disease (CAD). We compared the accuracy of both methods to detect significant CAD in a direct comparison. Methods: 79 patients (32 women, 47 men, mean age 62 years) who were admitted for coronary angiography due to suspected CAD were studied. By EBCT coronary calcification (CAC) as well as angiography (CTA) was assessed. Presence of significant CAD was assumed if the calcium score exceeded 400 or the contrast-enhanced images displayed significant lumen reduction. DSE was performed using a standard protocol (5–40 μg/kg/min dobutamine plus 0.25–1.0 mg atropine if necessary). DSE and EBCT were independently evaluated concerning the presence of signficant CAD. Results were compared to invasive, quantitative coronary angiography. Results: 6 patients (8%) in DSE and 2 patients (3%) in EBCT were unevaluable for various reasons and therefore excluded from further analysis. In the remaining 71 patients, 33 patients (46%) showed significant CAD. DSE demonstrated a sensitivity of 70% (23/33) and a specificity of 84% (32/38). EBCT showed a sensitivity of 91% (30/33) and a specificity of 74% (28/38). By combining DSE and EBCT sensitivity increased to 97% with a specificity of 63%. Conclusions: In a blinded comparison, DSE demonstrated lower sensitivity but higher specificity than EBCT for the detection of significant CAD. Sensitivity was improved by combining both modalities. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Three-dimensional echocardiography (3DE) improves the accuracy of left ventricle (LV) volumetry compared with the two-dimensional echocardiography (2DE) approach because geometric assumptions in the algorithms may be eliminated. The relationship between accuracy of mode (short- versus long-axis planimetry) and the number of component images versus time required for analysis remains to be determined. Sixteen latex models simulating heterogeneously distorted (aneurysmatic) human LVs (56–303 ml; mean 182 ± 82 ml) were scanned from an ‘apical’ position (simultaneous 2DE and 3DE). For 3DE volumetry, the slice thickness was varied for the short (C-scan) and long axes (B-scan) in 5-mm steps between 1 and 25 mm. The mean differences (true-echocardiographic volumes) were 16.5 ± 44.3 ml in the 2DE approach (95% confidence intervals –27.8 to +60.8) and 0.6 ± 4.0 ml (short axis; 95% confidence intervals –3.4 to +4.6) as well as 2.1 ± 9.9 ml (long axis; 95% confidence intervals –7.8 to +12.0) in the 3DE approach (in both cases, the slice thickness was 1 mm). Above a slice thickness of 15 mm, the 95% confidence intervals increased steeply; in the short versus long axes, these were –6.5 to +8.5 versus –7.0 to +10.6 at 15 mm and –10.1 to +15.7 versus –11.3 to +10.9 at 20 mm. The intra-observer variance differed significantly (p < 0.001) only above 15 mm (short axis). Time required for analysis derived by measuring short-axis slice thicknesses of 1, 15, and 25 mm was 58 ± 16, 7 ± 2 and 3 ± 1 min, respectively. The most rational component image analysis for 3DE volumetry in the in vitro model uses short-axis slices with a thickness of 15 mm. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]