Neo-sinus Flow Stasis Correlates with Thrombus Volume in Patients post-TAVR

SummaryIn vivo studies of the microcirculation of an untraumatized and unanesthetized animal preparation has shown that leukocyte adherence to vascular endothelium is an extremely rare occurrence. Induction of leukocyte adherence can be produced in a variety of ways including direct trauma to the vessels, remote tissue injury via laser irradiation, and denuding the epithelium overlying the observed vessels. The role of blood flow and local hemodynamics on the leukocyte adherence process is quite complex and still not fully understood. From the results reported it may be concluded that blood flow stasis will not produce leukocyte adherence but will augment pre-existing adherence. Studies using 2 quantitative measures of adherence, leukocyte flux and leukocyte velocity have shown these parameters to be affected differently by local hemodynamics. Initial adherence appears to be critically dependent on the magnitude of the blood shear stress at the vessel wall as evidenced by the lack of observable leukocyte flux above some threshold value. Subsequent behavior of the leukocytes as characterized by their average rolling velocity shows no apparent relationship to shear stress but, for low velocities, may be related to the linear blood velocity.

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SINUS AND NEO-SINUS FLOW EVALUATION AFTER IMPLANTATION OF AN EVOLUT, SAPIEN 3, ACCURATE NEO AND ALLEGRA TRANSCATHETER VALVES

Journal of the American College of Cardiology ◽

10.1016/s0735-1097(21)03064-3 ◽

2021 ◽

Vol 77 (18) ◽

pp. 1708

Author(s):

Hoda Hatoum ◽

Shelley Gooden ◽

Janarthanan Sathananthan ◽

Scott Lilly ◽

Abdul Rahman Ihdayhid ◽

...

Keyword(s):

Sapien 3 ◽

Transcatheter Valves ◽

Sinus Flow

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Carotid webs produce greater hemodynamic disturbances than atherosclerotic disease: a DSA time–density curve study

Journal of NeuroInterventional Surgery ◽

10.1136/neurintsurg-2021-017588 ◽

2021 ◽

pp. neurintsurg-2021-017588

Author(s):

Charlie C Park ◽

Retta El Sayed ◽

Benjamin B Risk ◽

Diogo C Haussen ◽

Raul G Nogueira ◽

...

Keyword(s):

Logistic Regression ◽

Carotid Artery ◽

Carotid Arteries ◽

Region Of Interest ◽

Hemodynamic Parameters ◽

Density Curve ◽

Atherosclerotic Lesions ◽

Clinically Significant ◽

Flow Stasis ◽

Time Density

BackgroundCarotid webs (CaWs) are associated with ischemic strokes in younger patients without degrees of stenosis that are traditionally considered clinically significant.ObjectiveTo compare the hemodynamic parameters in the internal carotid artery (ICA) bulbar segment in patients with CaW with those in patients with atherosclerotic lesions using time–density curve (TDC) analysis of digital subtraction angiography (DSA) images.MethodsWe retrospectively assessed DSA images of 47 carotid arteries in 41 adult patients who underwent ICA catheter angiography for evaluation after ischemic stroke. Hemodynamic parameters, including full width at half maximum (FWHM) and area under the time–density curve (AUC) as proxies for increased flow stasis, were calculated using TDC analyses of a region of interest (ROI) in the ICA bulb immediately rostral to the web/atherosclerotic plaque, relative to a standardized ROI in the ipsilateral distal common carotid artery (eg, relative FWHM (rFWHM)). Hemodynamic parameters were compared using non-parametric Kruskal-Wallis tests. Logistic regression was used to predict CaW versus mild/moderate atherosclerosis for each hemodynamic parameter, adjusting for degree of stenosis.ResultsMean age of patients was 56.0±13 years, with 22 (53.7%) women. 17 CaWs, 22 atherosclerotic plaques (15 mild/moderate and 7 severe), and eight normal carotid arteries were assessed. Significant between-group differences were present in the relative total AUC (p<0.001), relative AUC at wash out (p=0.031), and relative FWHM (p=0.001). Logistic regression to predict CaW versus mild/moderate atherosclerosis showed that rAUC total had the highest predictive value (pAUC=0.96, 95% CI 0.90 to 1.00), followed by rFWHM (0.87, 95% CI 0.74 to 1.00), and rAUC WO (0.74, 95% CI (0.57 to 0.91).ConclusionCaW results in larger local hemodynamic disruption, characterized by flow stasis, than mild/moderate carotid atherosclerotic lesions, suggesting that CaWs may produce larger regions of thrombogenic flow stasis.

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