Abstract 19527: Relation Between Quantitative Coronary Cta and Myocardial Ischemia by Adenosine Stress Ct Myocardial Perfusion
Background: Increasing stenosis severity is related to reduced myocardial blood flow during hyperemia. Stenosis percentage is a moderate predictor for myocardial ischemia. It is known that coronary plaque morphology and composition may improve discrimination. Integration of quantitative coronary CTA (QCT) and adenosine stress CT myocardial perfusion (CTP) provides this information. The aim of this study was to assess the relation between coronary stenosis severity and plaque characteristics by QCT and ischemia diagnosed by CTP.
Methods: We evaluated 84 patients who underwent both coronary CTA and adenosine stress CTP. Stenosis percentage and additional plaque characteristics (lesion length, mean plaque burden, plaque volume, remodeling index) were determined. Subsequently, the coronary lesions were related to presence of lesion specific ischemia measured with CTP.
Results: Atherosclerosis was present in 146 coronary arteries. 21% (33/146) of the lesions caused downstream ischemia. Stenosis percentage (p<0.001), mean plaque burden (p<0.001), plaque volume (p=0.021), lesion length (p=0.033), maximal plaque thickness (p=0.021), dense calcium volume (p=0.005) were higher in hemodynamically significant lesions. Only 1 (3%) of 37 coronary lesions ≤ 40% stenosis was related to ischemia. Between 41%-60%, 61%-80%, >81%, respectively, 17% (11/61), 34% (11/31) and 59% (10/17) were hemodynamically significant.
Conclusion: Increasing stenosis percentage measured by QCT is related to higher prevalence of hemodynamically significant lesions measured with adenosine stress CTP. However, stenosis severity cannot accurately detect ischemic lesions. Coronary plaque volume, mean plaque burden, lesion length, maximal lesion thickness, and dense calcium volume were other characteristics that were related to ischemia, potentially leading to improved discrimination of intermediate to severe stenotic coronary lesions for downstream ischemia.
Author Disclosures: A.R. van Rosendael: None. L.J. Kroft: None. M.A. de Graaf: None. A. Broersen: None. J.J. Bax: None. A.J. Scholte: None.
- © 2015 by American Heart Association, Inc.