Transesophageal examination of the left coronary artery with a 7.5 MHz annular array two-dimensional color flow Doppler transducer.

To determine the value of a recently developed 7.5 MHz annular array two-dimensional and color flow Doppler transducer for examination of the proximal parts of the left coronary artery, 25 patients were studied immediately after coronary artery bypass surgery, and the findings were compared with preoperative coronary angiograms. With two-dimensional imaging, the left main coronary artery was visualized in 22 patients (88%), left anterior descending in 13 patients (52%), and circumflex in 22 patients (88%). Stenoses were correctly identified in four of four left main coronary arteries, in five of seven left anterior descending arteries, and in none of four left circumflex arteries. Adding color flow to two-dimensional imaging in 20 patients, we found a disturbed flow signal, as a sign of stenosis, in five of five left anterior descending artery and two of four left circumflex artery stenoses. We concluded that these initial findings with this new 7.5 MHz annular array two-dimensional and color flow Doppler transducer, are promising in imaging and detection of stenoses in the proximal parts of the left coronary artery.