Morphological features of the left anterior descending coronary artery as revealed by high-frequency transthoracic echocardiography in normal subjects

This report describes the normal echocardiographic coronary wall features of the mid and apical segments of the left anterior coronary artery in 30 normal subjects as revealed by high-frequency transthoracic echocardiography. Both mid and apical segments were imaged in all subjects in short and long axis orientation. Their greatest length (as seen within the sector of a single frame) was respectively 21 +/- 6 and 17 +/- 5 mm, and the diameter and circumference were respectively 2.3 +/- 0.4 and 6.7 +/- 1 mm in the mid and 2.0 +/- 0.1 and 6.5 +/- 1 mm in the apical segment. In all subjects, the arterial wall was imaged as a smooth and regular echoreflective linear structure. In the mid segment of the 16 most echogenic subjects (53%), we distinguished a three-layered wall with a very thin and apparently noncontinuous line adjacent to the lumen, which was separated from the more echoreflective linear echo by a hypoechogenic space. A homogeneous red color-coded flow, filling the arterial lumen, was found in 14 of the 30 subjects (46%), in 8 of whom a spectral flow signal was also detected. These preliminary findings indicate that, in the near future, this method could become an effective part of the noninvasive armamentarium for the evaluation of coronary vessels and with further technological advances (e.g. an increase in carrier frequency) the quantitative noninvasive data concerning the thickness of the coronary wall may become a real possibility.