Author + information
- Arnav Kumar1,
- Olivia Y. Hung1,
- Parham Eshtehardi1,
- Elizabeth Thompson1,
- David Sternheim2,
- Sonu Gupta1,
- Karthic Chandran2,
- David S. Molony1,
- Marina Piccinelli3,
- Adrien Lefieux4,
- Michel T. Corban5,
- Michael C. McDaniel1,
- Arshed A. Quyyumi1,
- Bill D. Gogas1,
- Don P. Giddens6,
- Alessandro Veneziani4 and
- Habib Samady1
- 1Andreas Gruentzig Cardiovascular Center, Emory University School of Medicine, Atlanta, GA
- 2Division of Internal Medicine, Emory University School of Medicine, Atlanta, GA
- 3Department of Radiology, Emory University School of Medicine, Atlanta, GA
- 4Department of Mathematics and Computer Science, Emory University School of Medicine, Atlanta, GA
- 5Department of Cardiology, Mayo Clinic, Rochester, MN
- 6Georgia Tech and Emory University, Atlanta, GA
We hypothesized that wall shear stress (WSS) has incremental value over cardiovascular risk factors for predicting severe endothelial dysfunction (EDFx) in patients with non-obstructive coronary artery disease (CAD).
WSS was calculated in each 0.5 mm thick coronary segment in 44 patients with CAD by performing 3-D geometric reconstruction of baseline angiograms and computational fluid dynamics (Fig A). Low WSS was defined as <1 Pascal (Pa). Severe EDFx was defined as ≤-10% change in lumen diameter (%ΔD) in response to acetylcholine (ACh) infusion in each segment (Fig B).
Mean age was 51.2 ± 12.5 years, 73% were female and mean diameter stenosis was 20 ± 12%. In 4,510 segments analyzed, median WSS was 3.7 [IQR: 2.3 to 5.5] Pa and 1065 (24%) segments had severe EDFx. In univariable analysis, lower WSS (OR: 0.81, p < 0.001), older age (OR: 1.023; p < 0.001), female sex (OR: 2.39; p < 0.001), hypertension (OR: 1.43; p < 0.001) and smokers (OR: 1.37; p < 0.001) were associated with severe EDFx. In a multivariable logistic regression model, lower WSS (OR: 0.85; p < 0.001) was associated with severe EDFx independent of clinical risk factors. Addition of WSS to clinical risk factors resulted in a significant increase in global χ2 for a model predicting severe EDFx (p < 0.001) (Fig C). Similarly, in a multivariable linear regression model, a greater number of segments with low WSS (Beta: -0.13, p < 0.001) were independently associated with greater vasoconstriction (%ΔD) in response to ACh.
Among patients with non-obstructive CAD, lower WSS and greater area of low WSS were independently associated with severe endothelial dysfunction. Low WSS had an incremental value over clinical risk factors for predicting severe endothelial dysfunction.