Prospective Validation that Vulnerable Plaque Associated with Major Adverse Outcomes Have Larger Plaque Volume, Less Dense Calcium, and More Non-Calcified Plaque by Quantitative, Three-Dimensional Measurements Using Intravascular Ultrasound with Radiofrequency Backscatter Analysis

Whether quantitative, two-dimensional, and three-dimensional plaque measurements by intravascular ultrasound with radiofrequency backscatter (IVUS/VH) are different between intermediate lesions with or without major adverse cardiovascular events (MACE) is unknown. IVUS/VH-derived parameters were compared in 60 patients with an intermediate coronary lesion (40-70 %) between lesions that did or did not result in MACE over 12 months. IVUS/VH measurements were done at the site of the minimal lumen area (MLA) and on a per-plaque basis, defined by 40 % plaque burden. Pre-specified, adjudicated MACE events occurred in 5 of 60 patients (8.3 %). MACE lesions had larger plaque burden (65 % vs. 53 %, p = 0.004), less dense calcium (6.6 % vs. 14.7 %, p = 0.05), and more non-calcified plaque, mostly fibrofatty kind (17.6 % vs. 10 %, p = 0.02). Intermediate coronary lesions associated with MACE at 12 months have more plaque, less dense calcium, and more non-calcified plaque, particularly fibrofatty tissue by IVUS/VH.