Increased sensitivity of flow detection in the left coronary artery by transesophageal echocardiography after intravenous administration of transpulmonary stable echocontrast agent.

Transesophageal echocardiography (TEE) combined with color and pulsed Doppler allows a noninvasive assessment of flow in the proximal anterior descending coronary artery (LAD). The aim of this study was to assess whether the peripheral administration of a transpulmonary stable echocontrast agent with prolonged in vivo stability may improve the feasibility and accuracy of coronary flow detection by TEE Doppler. In 12 out of 14 consecutive patients undergoing routine diagnostic TEE examination, color-coded images of left main coronary artery (LM) and the origin of the LAD and circumflex artery (CXA), as well as spectral Doppler signals from the LAD, were evaluated before and after intravenous injection of SHU 508 A. After administration of echocontrast material, the coronary Doppler signal (both color-coded and spectral) was enhanced for approximately 100 seconds. The length and diameter of color-coded flow increased significantly in the LM, LAD, and CXA. (The length of color-coded flow before and after injection of contrast material were the following: in LM 0.94 +/- 0.44 versus 1.39 +/- 0.52 cm, p < 0.001; in LAD 0.68 +/- 0.36 versus 1.20 +/- 0.41 cm, p < 0.001; and in CXA 0.54 +/- 0.20 versus 1.06 +/- 0.86 cm; in this artery, color-coded flow was visualized only in six patients before and 11 patients after injection of contrast material. The corresponding values for the diameters of color-coded flow in LM were 0.36 +/- 0.08 versus 0.46 +/- 0.09 cm, p < 0.001; in LAD 0.29 +/- 0.07 versus 0.41 +/- 0.1 cm, p < 0.002; and in CXA 0.26 +/- 0.05 versus 0.40 +/- 0.04 cm.) By pulsed Doppler, significant increments in peak diastolic (47.8 +/- 21.3 versus 37.2 +/- 14.5 cm/sec, p < 0.05), mean diastolic (37.4 +/- 14.7 versus 27.9 +/- 8.4 cm/sec, p < 0.005), mean systolic flow velocity (23.2 +/- 6.8 versus 19.0 +/- 4.7 cm/sec, p < 0.005), and diastolic (11.0 +/- 3.9 versus 7.7 +/- 3.0 cm, p < 0.001) and total flow integral (16.8 +/- 5.3 versus 10.5 +/- 4.6 cm, p < 0.001) were observed. By contrast, peak systolic velocity did not increase. However, the systolic component of coronary flow, detectable in 7 out of 12 patients before injection of contrast material, became detectable in all 12 patients after injection of contrast material.(ABSTRACT TRUNCATED AT 400 WORDS)