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Relax & Read ⤵️ #Tweetorial by @CoronaryDoc + @arnavkumar
⚡️Coronary Wall Shear Stress in 12 Tweets ⚡️
1/12
Main Readings:
1) interventions.onlinejacc.org/content/early/…
2) ow.ly/XmD130mc9X8
3) link.springer.com/article/10.100…
#ACCImaging @ACCCardioEd
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Wall shear stress (#WSS) is the frictional force of blood exerted tangential to endothelial surface of vessel wall & expressed in variety of units (1Pa=1N/m2=10 dynes/cm2)
It is derived from
• luminal geometry
• flow rate
• blood viscosity
• near wall velocity values
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In vivo WSS calculations are derived from computational fluid dynamic (#CFD) simulations created from reconstructed 3D vessel geometries (from biplane angio/IVUS/OCT/CT/MR) combined with patient-specific pulsatile inlet/outlet velocity values (Doppler wire or other methods)
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#Mechanobiology
As a local mechanical force, WSS heavily affects bio-function of vascular endothelial & smooth muscle cells via diverse mechanisms ⤵️
Non-physiologic (⬇️ or ⬆️) WSS promote plaque progression & transformation of stable to unstable (high-risk) plaque
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#Endothelial dysfunction (EDFx) occurs early in development of atherosclerosis & is associated with worse CV outcome & angina
We showed for the first time that segments with ⬇️ WSS co-localize with severe EDFx in patients with non-obstructive CAD
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Longitudinal clinical studies have demonstrated that coronary segments exposed to ⬇️ WSS show significant plaque progression, change in plaque composition & constrictive remodeling; highlighting role of ⬇️ WSS in early development of #atherosclerosis
bit.ly/1q1b2qv
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⬆️ WSS induces specific changes in endothelial cell behavior, exacerbating inflammation and stimulating progression of atherosclerotic lipid core & has been shown in clinical studies to be associated with morphological features of high-risk (#vulnerable) plaque
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While geometry for WSS calculation was historically derived from #IVUS, WSS can also be derived from biplane #angiography, #MRA & #CTA
These promising modalities provide faster, more accessible, and less invasive method of CFD simulation & WSS calculation
#YesCCT
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Novel 3D vessel & scaffold/stent reconstruction to derive strut-level WSS has been used to to study @AbbottCardio #BVS device/flow interactions during bioresorption process
These novel methods of WSS assessment are expected to guide future stent design
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