Abstract 12134: Computational Analysis of Criteria Combinations for VH-TCFA: Analysis of Plaque Ulceration Locations
Background: Thin Cap Fibroatheroma (TCFA) rupture causes acute coronary syndromes (ACS). Arbitrarily defined Intravascular Ultrasound Radiofrequency (IVUS-VH) parameters of TCFA include necrotic core (NC) ≧10% without overlying fibrous tissue and percent plaque ≧40% based on abstraction from pathological samples. We sought plaque morphologic or compositional features that differentiate ulcerated plaque (U) from non-ulcerated plaque (NU) by computational analysis with the accepted IVUS-VH TCFA and 105 additional definitions.
Methods: IVUS-VH with automated pullback was performed in 72 plaques in 72 patients presenting with ACS or stable angina pectoris (SAP): 16 U and 56 NU. IVUS-VH data underwent blinded adjudication with VIAS software. IVUS data between U and NU were compared by t-test for morphology and by Fisher's exact test with correction for multiple comparisons for compositional features assessing 106 different criteria combinations for TCFA in 3-slice VH samples. Definitions altered NC % (>5%, >10%, >15%, >20%, >25%), NC absolute and relative luminal distance, extent of lumen contact, excluding NC behind dense calcium (DC), 2-D or 3-D connectivity of NC to lumen, and arc of NC.
Results: There were 16 plaques with ulceration: 7 LAD, 2 LCX, and 7 RCA, 11 ulcerations in ACS and 5 in SAP. Minimal lumen cross sectional area (CSA) was significantly larger in U (p<0.05), but average plaque and adventitial CSA and IVUS-VH morphologic indices did not differ. Analysis of the 106 TCFA criteria combinations revealed 3 definitions which differed between U and NU in ACS patients, but after multiple test correction, significance was lost.
Conclusion: U were found to have a larger minimal lumen CSA than NU but had no other distinguishing morphologic features or measures of plaque burden. Despite extensive computer modeling of 106 TCFA definitions including the standard VH-TCFA definition, no constellation of findings could distinguish IVUS-VH derived features of NU vs U.
- Intravascular ultrasound/Doppler
- Plaque rupture
- Vulnerable plaque
- Acute coronary syndromes
- Interventional studies
- © 2012 by American Heart Association, Inc.