Intravascular ultrasound assessment of the stenoses location and morphology in the left main coronary artery in relation to anatomic left main length

Eighty-seven left main stenoses were evaluated by angiography and intravasc ular ultrasound. Intravascular ultrasound analysis included left main lengt h (bifurcation to ostium), stenosis location, stenosis length, stenosis ext ernal elastic membrane, lumen, plaque & media cross-sectional area (CSA), p laque burden (plaque & media/external elastic membrane CSA), calcium are, c alcium length, eccentricity, and remodeling index (stenosis/reference exter nal elastic membrane CSA). long anatomic left main arteries (length greater than or equal to 10 mm, n = 43) were compared with short anatomic left mai n arteries (length < 10 mm, n = 44) regarding stenosis location. Ostial (pr oximal third of left main artery) (n 32) and nonostial (midthird and distal third) stenoses (n = 55) were compared regarding stenosis morphology. Shor t anatomic left main arteries developed stenoses more frequently near the o stium (ostium 55%, bifurcation 38%). Conversely, long anatomic left main ar teries developed stenoses more frequently near the bifurcation (ostium 18%, bifurcation 77%, p = 0.001). Ostial left main stenoses were more common in women (44% vs 20%, p = 0.02), had larger lumen area (6.2 +/- 2.2 vs 4.6 +/ - 2.3 mm(2), p = 0.002), less plaque burden (62 +/- 15% vs 80 +/- 9%, p <0. 0001), less calcification tare = 78 +/- 65 degrees vs 195 +/- 101 degrees, p <0.0001), and more negative remodeling (remodeling index = 0.87 +/- 0.19 vs 1.01 +/- 0.21, p = 0.005) than nonostial left main ste; noses. Most osti al left main stenoses were categorized as eccentric (97% vs 76%, p = 0.01). Short and long left main arteries develop stenoses at different locations. Stenosis morphology was significantly different in these 2 locations. (C) 2001 by Excerpta Medico, Inc.