Improved endocardial border delineation during dobutamine stress echocardiography using the left heart contrast medium BY 963
The interpretation of induced wall motion abnormalities during dobutamine stress echocardiography is affected in the case of impaired image quality. In 48 consecutive patients (mean age 62 +/- 9 years, 32 males, 16 females) with suspected coronary disease undergoing coronary angiography, the transpulmonary contrast agent BY 963 was given i.v. as bolus during dobutamine stress echocardiography (10-40 micrograms kg min, plus max. 1 mg atropine) to analyze improvements in endocardial border delineation. For each of the 16 segments of the left ventricle, the endocardial border delineation was evaluated. Using BY 963 the average number of non-evaluable segments decreased by 58% from 5.2% to 2.2% at rest (p = 0.008) and by 56% from 5.9% to 2.6% at maximal stress (p = 0.003) as compared to the non-contrast study for all patients. In patients with impaired image quality, defined as at least 1 non-evaluable segment at rest without contrast enhancement (N = 14), the number of non-evaluable segments decreased from 19.2% to 8.2% (p = 0.004) at rest and from 19.2% to 9.6% (p = 0.006) at maximal stress. The greatest decrease of non-evaluable segments was seen in the lateral and anterior segments of the apical views (maximum of 80%). The improved endocardial border delineation resulted in an improved agreement between two observers in the interpretation of the dobutamine stress echocardiograms as positive or negative (kappa = 0.38 without contrast, kappa = 0.58 with contrast). Contrast application resulted in a slight improvement of diagnostic accuracy of dobutamine stress echocardiography in the detection of angiographically proven significant coronary artery disease.
Conclusions: In patients with impaired endocardial border delineation the use of the echo contrast agent BY 963 reduces the number of non-evaluable segments. Improvement of endocardial delineation is greatest for lateral and anterior segments in the apical views.