Objective: To compare real-time three-dimensional echocardiography (RT3DE) with two-dimensional dobutamine stress echocardiography (2DE) for the detection of myocardial ischaemia, with angiographic validation of the results. Methods: 56 patients (mean (SD) age 64.5 (6.2) years, 38 males), referred for coronary angiography, were examined by 2DE and RT3DE during the same dobutamine stress protocol. Results: All 56 patients completed the stress protocol uneventfully. The mean (SD) acquisition time for the necessary views to evaluate all segments was 26.3 (2.5) s for RT3DE and 58.8 (3.7) s for 2DE (p,0.001). At peak stress, RT3DE had a higher wall-motion score index (1.25 (0.24) by 2DE, 1.30 (0.27) by RT3DE; p = 0.014). The regional wall-motion score for the four apical segments at peak stress was compared; it was 1.35 (0.55) by 2DE and 1.52 (0.69) by RT3DE (p = 0.003). The diagnostic parameters of 2DE versus RT3DE were: sensitivity 73% vs 78%, specificity 93% vs 89% and overall accuracy 86% vs 85%, respectively. In the left anterior descending artery territory, in particular, where RT3DE had higher regional wall-motion scores, it showed a tendency towards higher sensitivity (85% vs 78%), although this difference did not achieve statistical significance. Conclusion: RT3DE identifies wall-motion abnormalities more readily in the apical region than 2DE, which may explain the tendency towards higher sensitivity in the left anterior descending artery territory. RT3DE results were validated using angiography as reference and findings indicate diagnostic equivalence to 2DE, with the advantage of considerable shorter acquisition times. D obutamine stress echocardiography has become a well established method of myocardial functional assessment in the diagnosis of coronary artery disease and in evaluation of its prognosis.1-4 The advent of echocardiography machines integrating all necessary systems for performing realtime three-dimensional echocardiography (RT3DE) holds promise as a new useful tool in cardiovascular ultrasonographic imaging. However, the clinical utility of this tool has yet to be adequately investigated. Particularly in the field of diagnosis of coronary artery disease, there is a marked lack of data regarding the usefulness of RT3DE. Our aim was to evaluate RT3DE in detecting myocardial wall-motion abnormalities during a standard dobutamine stress protocol, in comparison to twodimensional echocardiography (2DE), with coronary angiography as the reference method for assessing the diagnostic power of this modality (fig 1).
METHODS
Study populationThe study population included 56 patients (mean (SD) age 64.5 (6.2) years, 38 males), referred for coronary angiography to the cardiac catheterisation laboratory of a tertiary hospital. All patients were in sinus rhythm. Exclusion criteria included the presence of symptoms of heart failure, a suspected or proven acute coronary event within the previous month, history of sustained ventricular tachycardia, moderate or severe valvular disease, uncontrolled hypertension...