Definitions and Methodology for the Grayscale and Radiofrequency Intravascular Ultrasound and Coronary Angiographic Analyses

• Published in: JACC. Cardiovascular imaging 2012-03, Vol.5 (3), p.S1-S9
• Main Authors: Maehara, Akiko, MD, Cristea, Ecaterina, MD, Mintz, Gary S., MD, Lansky, Alexandra J., MD, Dressler, Ovidiu, MD, Biro, Sinan, MSc, Templin, Barry, MBA, Virmani, Renu, MD, de Bruyne, Bernard, MD, PhD, Serruys, Patrick W., MD, PhD, Stone, Gregg W., MD
• Format: Article
• Language: English
• Subjects: Aged; Angioplasty, Balloon, Coronary - adverse effects; Angioplasty, Balloon, Coronary - mortality; Cardiovascular; Coronary Angiography - standards; Coronary Artery Disease - classification; Coronary Artery Disease - diagnostic imaging; Coronary Artery Disease - mortality; Coronary Artery Disease - therapy; Coronary Stenosis - classification; Coronary Stenosis - diagnostic imaging; Coronary Stenosis - mortality; Coronary Stenosis - therapy; Disease Progression; Europe - epidemiology; Female; Fibrosis; Humans; Image Processing, Computer-Assisted - standards; Male; Middle Aged; Multivariate Analysis; Neointima - diagnostic imaging; Predictive Value of Tests; Prospective Studies; Risk Assessment; Risk Factors; Severity of Illness Index; Terminology as Topic; Time Factors; Treatment Outcome; Ultrasonography, Interventional - standards; United States - epidemiology; Vascular Calcification - diagnostic imaging
• ISSN: 1936-878X; 1876-7591
• DOI: 10.1016/j.jcmg.2011.11.019

Objectives In a prospective study of the natural history of coronary atherosclerosis using angiography and grayscale and radiofrequency intravascular ultrasound (IVUS)–virtual histology (VH), larger plaque burden, smaller luminal area, and plaque composition thin-cap fibroatheroma emerged as independent predictors of future adverse cardiovascular events. Background The methodology for IVUS-VH classification for an in vivo natural history study and the prospective image mapping by angiography and grayscale and IVUS-VH have not been established. Methods All culprit and nonculprit lesions (defined as ≥30% angiographic visual diameter stenoses) were analyzed. Three epicardial vessels as well as all ≥1.5-mm-diameter side branches were divided into 29 CASS (Coronary Artery Surgery Study) segments. Each CASS segment was then subdivided into 1.5-mm-long subsegments, and dimensions were analyzed. All grayscale and IVUS-VH slices from the proximal 6 to 8 cm of the 3 coronary arteries were analyzed, with lesions defined as having more than 3 consecutive slices with ≥40% plaque burden categorized as: 1) VH thin-cap fibroatheroma; 2) thick-cap fibroatheroma; 3) pathological intimal thickening; 4) fibrotic plaque; or 5) fibrocalcific plaque. The locations of angiographic and grayscale and IVUS-VH lesions were recorded in relation to the corresponding coronary artery ostium and nearby side branches. Results The 3-year cumulative rate of major adverse cardiovascular events was 20.4%. Events were adjudicated to culprit lesions in 12.9% of patients and to nonculprit lesions in 11.6%. On multivariate analysis, nonculprit lesions associated with recurrent events were characterized by a plaque burden ≥70% (hazard ratio: 5.03; 95% confidence interval: 2.51 to 10.11; p < 0.0001), a minimal luminal area ≤4.0 mm2 (hazard ratio: 3.21; 95% confidence interval: 1.61 to 6.42; p = 0.001), and IVUS-VH phenotype of a thin-cap fibroatheroma (hazard ratio: 3.35; 95% confidence interval: 1.77 to 6.36; p < 0.001). Conclusions Three-vessel multimodality coronary artery imaging was feasible and allowed the identification of lesion-level predictors for future events in this natural history study.