IN-VITRO ASSESSMENT OF LUMINAL DIMENSIONS OF CORONARY-ARTERIES BY INTRAVASCULAR ULTRASOUND WITH AND WITHOUT APPLICATION OF ECHOGENIC CONTRAST DYE

To evaluate the impact and limitations of intracoronary ultrasound in the assessment of lumen, we examined 80 segments of 20 isolated corona ry arteries with a mechanical ultrasound device (CVIS) comparing the r esults of ultrasound with the corresponding histological specimens. Ul trasound was performed with and without echogenic contrast dye (Laevov ist, Schering AG, FRG). After application of contrast dye, correlation of luminal area between histology and ultrasound was improved from r = 0.85 to r = 0.89 (p = ns). Accuracy of lumen measurements was low in segments <2.5 mm; only after application of contrast dye a relationsh ip between ultrasound and histological measurements was found. In all cases in which a deviation of more than 20 % between ultrasound and hi stology was observed, this deviation could be reduced by the applicati on of contrast dye. There are considerable limitations in the accuracy of ultrasound measurements in the near field. Thus, further improveme nt of intracoronary ultrasound devices is mandatory. However, with the use of the currently available systems, additional application of ech ogenic contrast dye can improve accuracy of luminal measurements, espe cially in smaller size vessels.