Abstract 15068: Impact of Out-stent Plaque Vulnerability on Neointimal Stent Coverage in Patients with Acute Coronary Syndrome: Intracoronary Angioscopic and Ultrasonic Quantification

Background: Intracoronary angioscopy is a unique imaging device to visualize in-stent neointimal coverage (ISNC). iMAP intravascular ultrasound (IVUS) quantitates not only plaque burden but also its tissue characterization. The aim of this study was to clarify the healing process of stented vulnerable plaques in patients with acute coronary syndrome (ACS). Methods: In 27 patients with ACS (18 acute myocardial infarction and 9 unstable angina), a bare metal stent (n=6) or a drug-eluting stent (n=21) was successfully implanted at each culprit lesion. Subsequently, out-stent vulnerable plaques were characterized by 40 MHz iMAP IVUS, i.e. out-stent plaque volume (OSPV) and its % tissue fractions of fibrotic, lipidic, necrotic, or calcified volumes. OSPV was defined as integral calculation of out-stent plaque area per 0.5mm interval, from proximal to distal edge of each stent. At one-year follow-up (chronic phase), in addition to iMAP IVUS analysis, coronary angioscopy was performed to assess ISNC grade (grade...