Intermediate Coronary Artery Stenoses: An Intravascular Ultrasound Study

In symptomatic coronary patients angiographically intermediate Jesions are commonly observed, and the decision to revascularize requires f urther evaluation of these stenoses. Intravasc ular ultiasound imaging is one of the ava ilable techniques to solve this problem. In 50 lesions in which quantitative coronary angiography showeel 78 49,0 ± 6,5 percent diameter stenos is, the quantitative and qualitative lesion assessments were performed using intravascular ultrasound. Percent cross-sectional area stenoses changed from 33% to 87%, and m ean plaque burden was 67 ,O ± 12,4%. As 18 (36%) lesions had plaque burden between 50% and 70%, 26 (52%) lesions showeel plaque burden over 70%. The lesion lumen cross-sectional area <4 mın2 was found in 30 (60%) stenoses. Lower plaque eccentricity index (0.4 ± 0,3) defined the eccentric plaque ınorphol ogy of these lesions. In 25 (50%) les ions the existence of a disease-free are with high eccentricity of the lumen was conspicuous. Soft and mixed plaques were frequently seen. Calcification was observed in 16%. Atherosclerosis was not founcl in 17 (34%) reference segınents, but plaque burden was >40% in 14 (28%) reference segınents. Ineffect ive arterial remodeling was found in 14 (28%) lesions. Compensatory dilation was revealed in 15 (30%). Plaque burden was lower in lesions with inadequate arterial reınodeling than in lesions with coınpensatory dilation. In comparison with the measurements of quantitative coronary angiography, intravascular ultrasound findings showeel hig her minimal lumen diameters (2,1 ± 0,5 ının, 1,8 ± 0,6 mm, pKeywords: intermediate lesion , intravascular ultrasound, coronary angiography