High volume-rate three-dimensional stress echocardiography to assess inducible myocardial ischemia: a feasibility study.

BACKGROUND

Compared with previous three-dimensional (3D) echocardiographic scanners, high-volume rate scanners allow higher temporal resolution and the possibility of displaying cropped images side by side. These new features make 3D echocardiography (3DE) even more attractive for application during stress. The aim of this study was to compare the feasibility and diagnostic accuracy of high-volume rate 3DE with state-of-the-art two-dimensional echocardiography (2DE) in detecting ischemia during dipyridamole-induced stress (DipSE).

METHODS

One hundred seven consecutive patients with known or suspected coronary artery disease were examined using 2DE and 3DE during the same DipSE examination.

RESULTS

Seventeen patients with inadequate images on 2DE requiring contrast infusion and 6 patients with inadequate detection of the endocardial borders on 3DE were excluded (feasibility of 3DE, 79%). The diagnostic accuracy of 3DE with DipSE was tested in the remaining 84 patients. Both acquisition time (65 +/- 30 s vs 16 +/- 3 seconds, respectively; P < .0001) and analysis time (176 +/- 63 vs 91 +/- 5 seconds, respectively; P < .0001) were significantly longer with 2DE than 3DE. Temporal resolution was significantly higher with 2DE than 3DE (75 +/- 5 frames/s vs 41 +/- 5 volumes/s, respectively; P < .0001). The wall motion score index (WMSI) at baseline was similar with 2DE and 3DE (1.041 +/- 0.023 vs 1.049 +/- 0.01, respectively; P = NS). In contrast, peak stress WMSI was significantly lower with 2DE than 3DE (1.21 +/- 0.025 vs 1.29 +/- 0.023, respectively; P = .011). In particular, mean apical peak stress WMSI was significantly lower with 2DE than 3DE (1.34 +/- 0.057 vs 1.55 +/- 0.078, respectively; P < .0001). In the 44 patients who underwent coronary angiography, the overall accuracy of 3DE was similar to that of 2DE (sensitivity, 80% vs 78%; specificity, 87% vs 91%). In the left anterior descending coronary artery territory, for which 3DE showed higher WMSI values, the sensitivity of 3DE was significantly higher than that of 2DE (87% vs 78%, P = .011), while specificity was similar.

CONCLUSIONS

Three-dimensional echocardiography with DipSE is feasible and offers shorter acquisition and analysis times compared with 2DE, with similar overall diagnostic accuracy. However, the ability of 3DE to identify wall motion abnormalities in the apical region explains its higher sensitivity for the left anterior descending coronary artery territory.