Abstract 1665: Variation of Plaque Composition and Tissue Redistribution After Balloon Angioplasty in Coronary Atherosclerotic Lesions: Study Using “Virtual Histology” by Spectral Analysis of Intravascular Ultrasound Radiofrequency Data
Background: Spectral analysis of intravascular ultrasound (IVUS) radiofrequency data (IVUS-virtual histology (VH)) has shown potential to provide quantitative information about plaque composition. We aimed to assess changes in coronary atherosclerotic plaque after balloon angioplasty (BA) using IVUS-VH analysis.
Methods: In 18 pts (4 stable angina, 14 acute coronary syndrome), 20 lesions were investigated before and immediately after BA by IVUS-VH using a mechanical 30 Mhz probe with motorized pullback at 0.5mm/s. Lesion site, proximal & distal reference were defined according to ACC criteria. Volumetric data were calculated using Simpson’s rule. The cross-sectional area (CSA) of the lumen, vessel, plaque+media (P+M) and the volume of 4 different plaque components (fibrous, fibro-fatty, necrotic core and dense calcium) were compared before and after BA at lesion site, proximal & distal references.
Results: At lesion site, there was a significant increase in lumen CSA(+65%), due to an increase in vessel CSA (−10%) and a decrease in plaque (−10%); the decreased plaque was mainly composed of necrotic core (−50%). At the proximal reference, there was a significant decrease in lumen CSA (−15%), attributed to the increase in plaque (+20%), which was mainly composed of fibrous (+20%) and fibro-fatty (+35%) components. At the distal reference, there was no significant change in any variable.
Conclusion: IVUS-VH makes it possible to show that BA causes a longitudinal redistribution of atherosclerotic plaque and provides quantitative estimations of these changes.