Abstract 17975: Coronary and Myocardial Blood Flow Measurements Derived from Coronary Computed Tomography Angiography and Transluminal Attenuation Flow Encoding in the Multicenter AIDS Cohort Study
Introduction: Coronary computed tomography angiography (CTA) is a powerful tool for the assessment of coronary stenosis and plaque burden. However, CTA lacks an assessment of coronary blood flow (CBF), an important determinant of patient outcome. The purpose of this study was to measure CBF using a novel method - Transluminal Attenuation Flow Encoding (TAFE) in the Multicenter AIDS Cohort Study (MACS) and assess the relationship between blood flow and measurements of stenosis and plaque burden.
Methods: The MACS is a multicenter study of men with or at risk for HIV infection with 181 subjects undergoing 320 detector CTA and TAFE analysis. TAFE-derived CBF in ml/min was calculated from the transluminal attenuation gradient, vessel cross-sectional area and length, and the arterial input function measured from bolus tracking data. Myocardial blood flow (MBF) was calculated from the ratio of CBF/myocardial mass in ml/min/g. Independently, coronary CTA was analyzed for stenosis and plaque burden using a semiquantitative total stenosis score and total, calcified, non-calcified and mixed plaque scores using the sum of coronary segmental scores of stenosis or plaque severity. Multivariable linear regression was used to assess the association between MBF, stenosis and each plaque score. Models were adjusted for age and race.
Results: Mean CBF was 42.4±19.7 and 29.1±19.3 ml/min in the left and right coronary arteries, respectively. MBF was lower in men with coronary stenosis ≥50% (-0.15 [-0.27, -0.03], p=0.01). MBF was significantly associated with total stenosis score and total plaque score (Table). There was no difference in MBF in HIV seropositive vs. seronegative men, 0.70±0.32 vs 0.72±0.28, p=0.929.
Conclusions: TAFE-derived CBF measurements, normalized to myocardial mass, are associated with coronary stenosis and total plaque burden; but not HIV serostatus. TAFE has the potential to extend coronary CTA to the evaluation of coronary hemodynamics.
Author Disclosures: R.T. George: Research Grant; Significant; Toshiba, General Electric. Consultant/Advisory Board; Significant; ICON Medical Imaging. A.A. Rahsepar: None. P. Eslami: None. J.H. Seo: None. R. Mittal: Other; Modest; Patent Pending. D. Zhao: None. E. Guallar: None. L.P. Jacobson: Consultant/Advisory Board; Modest; Bristol Myers Squibb. M. Budoff: None. W.S. Post: None. A.C. Lardo: Other; Modest; Patent Pending.
- © 2014 by American Heart Association, Inc.