scholarly journals Quantitative Evaluation of Peripheral Arterial Blood Flow Using Peri-Interventional Fluoroscopic Parameters: An In Vivo Study Evaluating Feasibility and Clinical Utility

2020 ◽  
Vol 2020 ◽  
pp. 1-8 ◽  
Author(s):  
Patrick Ghibes ◽  
Gerald Hefferman ◽  
Konstantin Nikolaou ◽  
Roland Syha ◽  
Christoph Artzner ◽  
...  
Keyword(s):  
Area Under The Curve ◽  
Arterial Disease ◽  
Arterial Blood Flow ◽  
Time Resolved ◽  
Complementary Method ◽  
Time To Peak ◽  
Arterial Blood ◽  
Fluoroscopic Imaging ◽  
Peripheral Arterial

Purpose. The purpose of this study was to evaluate various objective, quantitative, time-resolved fluoroscopic imaging parameters for use in the peri-interventional evaluation of stenotic peripheral arterial disease lesions. Material and Methods. Ten patients (median age, 64; age range, 52 to 79; 8 males, 2 females) with high-grade stenoses of either the superficial femoral or popliteal arteries who underwent endovascular treatment were included. During each intervention, two series of intraprocedural fluoroscopic images were collected, one preintervention and one postintervention. For each imaging series, four regions of interest (ROIs) were defined within the vessel lumen, with two ROIs being proximal (ROIs 1 and 2) and two being distal (ROIs 3 and 4) to the stenosis. The time-density curve (TDC) at each ROI was measured, and the resulting area under the curve (AUC), full width at half maximum (FWHM), and time-to-peak (TTP) were then calculated. Results. The analysis of the TDC-derived parameters demonstrated significant differences between pre- and postinterventional flow rates in the ROI placed most distal to the stenosis, ROI 4. The AUC at ROI 4 (reported as a relative percentage of the AUC measured at ROI 1 proximal to the lesion) demonstrated a significant increase in the total flow (mean 67.84% vs. 128.68%, p=0.003). A significant reduction in FWHM at ROI 4 (mean 2.93 s vs. 1.87 s, p=0.015) was observed. A significant reduction in TTP at ROI 4 (2.43 s to 1.45 s, p=0.009) was also observed. A positive change in at least 1 of the 3 calculated parameters was seen in all patients after a successful intervention, with 7 of 10 patients showing improvement in all 3 parameters, 2 of 10 showing improvement in 2 parameters, and 1 patient showing improvement in 1 parameter. Conclusion. AUC, FWHM, and TTP are objective, reproducible, quantifiable tools for the peri-interventional fluoroscopic evaluation of vessel stenoses. When compared to the standard subjective interpretation of fluoroscopic imagery, AUC, FWHM, and TTP offer interventionalists the advantage of having an objective, complementary method of evaluating the success of a procedure, potentially allowing for more precisely targeted and quantitatively determined treatment goals and improved patient outcomes. This retrospective study was approved by the local ethics committee under the Number 372/2018BO2. The trial was registered at the German clinical trials register under the number DRKS00017813.

Spiral Laminar Flow in Vivo

1996 ◽  
Vol 91 (1) ◽  
pp. 17-21 ◽  
Author(s):  
P. A. Stonebridge ◽  
P. R. Hoskins ◽  
P.L. Allan ◽  
J. F. F. Belch
Keyword(s):  
Blood Flow ◽  
Reverse Flow ◽  
Arterial Disease ◽  
Flow Patterns ◽  
Endothelial Damage ◽  
Arterial Blood Flow ◽  
Arterial Tree ◽  
Arterial Blood ◽  
Blood Flow Patterns

1. Blood flow patterns are poorly understood despite their impact on arterial disease. There have been few measurements in vivo of the three-dimensional blood flow patterns; we present the results of such studies using a new non-invasive in-vivo method of examining biplanar arterial blood flow patterns. 2. Multiple colour Doppler ultrasound directional velocity images were obtained at two different beam target angles from the artery in the plane perpendicular to its axis. Ensemble average images were constructed; the absolute velocity and direction were calculated by compounding the left and right averaged images. Simple directional, non-directional velocity and vector maps were constructed. 3. Flow patterns were sampled in 11 healthy male volunteers at four points of the pulse cycle; peak systole, systolic downswing, diastolic reverse flow and diastolic forward flow and at three sites; the right common and distal superficial femoral and the left common femoral arteries. 4. Stable rotational flow was observed in all subjects, the direction of rotation varying between sides and individuals. 5. There are theoretical advantages to spiral laminar blood flow; the forward-directed, rotationally induced stability and reduction of laterally directed forces may reduce turbulence in the tapering branching arterial tree and at stenoses and have a beneficial effect on mechanisms of endothelial damage and repair.

Abstract TP63: Detection of Perfusion Deficits Using FLAIR and GRE Based Vessel Signs

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Dennys Reyes ◽  
Emi Hitomi ◽  
Alexis Simpkins ◽  
John Lynch ◽  
Amie Hsia ◽  
...  
Keyword(s):  
Acute Stroke ◽  
Roc Analysis ◽  
Area Under The Curve ◽  
Arterial Blood Flow ◽  
Lesion Volume ◽  
Perfusion Deficit ◽  
Stroke Patients ◽  
Time To Peak ◽  
Arterial Blood ◽  
Perfusion Deficits

Background: The presence of a perfusion deficit in an acute stroke patient can play an important role in their clinical management. However, many patients are unable to have perfusion-weighted imaging (PWI) due to renal disease. Perfusion deficits are often accompanied by FLAIR hyperintense vessels (FHV), presumably due to slow arterial blood flow, and GRE hypointense vessels (GHV), presumably due to venous congestion. Purpose: To determine how well FHV and GHV perform at identifying PWI lesions. Methods: One rater, blinded to the PWI MR sequences, retrospectively reviewed the DWI, FLAIR and GRE scans of acute stroke patients enrolled in the NIH Natural History of Stroke study during 2013-2014 who had an MRI with PWI prior to being treated with IV tPA. DWI images were used to guide evaluation of the FLAIR and GRE images for FHV and GHV and in each case were classified as definitively present, possibly present or absent. PWI lesion volumes were calculated by thresholding the time-to-peak (TTP) maps at 4 seconds beyond normal tissue. ROC analysis was used to assess the performance of FHV and GHV at various PWI lesion volume thresholds. Results: 102 patients were included in the analysis; their mean PWI lesion volume was 52 mL with a standard deviation of +/- 66 mL. 22% of patients had no perfusion deficit. The ROC analysis found the presence of any FHV performed the best with an area under the curve (AUC) of 0.925 displayed in the figure. Any GHV performed modestly with an AUC of 0.776. Combining FHV with GHV did not improve the performance over FHV alone (AUC=0.876). The sensitivity and specificity for identifying any perfusion deficit with FHV was 95% and 67% respectively with 87% being correctly classified. For detecting a PWI lesion greater than 10 mL, FHV had an 80% sensitivity and 93% specificity classifying 83% correctly. Conclusions: FHV is highly sensitive for identifying a perfusion deficit in stroke patients, and for patients with a lesion volume greater than 10 mL it is highly specific.

scholarly journals The Rise of Mitochondria in Peripheral Arterial Disease Physiopathology: Experimental and Clinical Data

2019 ◽  
Vol 8 (12) ◽  
pp. 2125 ◽  
Author(s):  
Mégane Pizzimenti ◽  
Marianne Riou ◽  
Anne-Laure Charles ◽  
Samy Talha ◽  
Alain Meyer ◽  
...  
Keyword(s):  
Peripheral Arterial Disease ◽  
Ischemia Reperfusion ◽  
Arterial Disease ◽  
Oxidative Capacity ◽  
Arterial Blood Flow ◽  
Limb Amputation ◽  
Retention Capacity ◽  
Arterial Blood ◽  
Promising Therapeutic Approach ◽  
Peripheral Arterial

Peripheral arterial disease (PAD) is a frequent and serious condition, potentially life-threatening and leading to lower-limb amputation. Its pathophysiology is generally related to ischemia-reperfusion cycles, secondary to reduction or interruption of the arterial blood flow followed by reperfusion episodes that are necessary but also—per se—deleterious. Skeletal muscles alterations significantly participate in PAD injuries, and interestingly, muscle mitochondrial dysfunctions have been demonstrated to be key events and to have a prognosis value. Decreased oxidative capacity due to mitochondrial respiratory chain impairment is associated with increased release of reactive oxygen species and reduction of calcium retention capacity leading thus to enhanced apoptosis. Therefore, targeting mitochondria might be a promising therapeutic approach in PAD.

Fibrinolyse- und Thrombophilieparameter unter systemischer Prostaglandin E1-Therapie bei peripherer arterieller Verschlusskrankheit

VASA ◽  
2003 ◽  
Vol 32 (3) ◽  
pp. 145-148 ◽  
Author(s):  
Kuss ◽  
Heidrich ◽  
Koettgen
Keyword(s):  
Coagulation Factor ◽  
Plasminogen Activator Inhibitor ◽  
Bleeding Risk ◽  
Arterial Disease ◽  
Prostaglandin E ◽  
Factor Xii ◽  
Significant Difference ◽  
Peripheral Arterial ◽  
Fibrinolytic Capacity

Background: The study was designed to evaluate if there is any evidence of a hyperfibrinolytic bleeding-risk under systemic treatment with prostaglandin E1 (PGE1) of patients with peripheral arterial disease (PAD). Patients and methods: The in vivo effect of PGE1 on the fibrinolytic and hemostatic process was tested on 15 patients before and after treatment with Alprostadil for 21 days using D-dimers (DD), fibrinogen, prothrombin time (PT), partial thromboplastin time (PTT), antithrombin (AT), ProC-Global®, plasminogen, plasminogen activator inhibitor activity (PAI), alpha2-antiplasmin, coagulation factor XII, basal and activated fibrinolytic capacity (fib. cap.). Results: There was no significant difference in DD, fibrinogen, PT, PTT, AT, ProC-Global®, plasminogen, PAI, alpha2-antiplasmin, coagulation factor XII, basal and activated fibrinolytic capacity observed after the treatment. Conclusion: Summarizing this study there is no hyperfibrinolytic bleeding-risk after the systemic therapy with Alprostadil to be expected.

scholarly journals Optical Coherence Elastography Techniques for Carotid Arterial Wall Imaging

2021 ◽  
Author(s):  
Felix Nolte
Keyword(s):  
Axial Strain ◽  
Image Correlation ◽  
Arterial Blood Flow ◽  
Lateral Strain ◽  
Optical Coherence ◽  
Phantom Experiment ◽  
Arterial Blood ◽  
Speckle Patterns ◽  
Imaging Mode

In this thesis, elastography is evaluated in combination with optical coherence tomography (OCT). Two approaches to OCT based elastography, Digital image correlation (DIC) and Doppler optical coherence elastography (DOCE), are evaluated for an intravascular setup using in vivo images from a porcine carotid model. DIC tracks the displacement of speckle patterns in consecutive frames, allowing the calculation of axial and lateral strain. Rapid speckle decorrelation was observed in preprocessed structural images, affecting the tracking and limiting the feasibility of this algorithm. DOCE measures axial strain based on relative tissue velocities. Rotational movement of the imaging optical fibre was the biggest source of artefacts in this imaging mode, but could be removed with a newly developed algorithm, based on the phase change induced in a surrounding catheter. The standard deviation of phase after artefact removal, measured in a stationary phantom experiment, was ~0.2 rad, corresponding to a minimum detectable velocity of 792 μm/s at a Doppler angle of 20°. The sensitivity allowed the detection of arterial blood flow velocity and pattern and the detection of adjacent veins, but did not allow direct elastography.

Abstract 249: Delayed Gene Transfer Increases Transgene Expression in Vein Grafts

2013 ◽  
Vol 33 (suppl_1) ◽  
Author(s):  
Liang Du ◽  
Jingwan Zhang ◽  
Alexander Clowes ◽  
David Dichek
Keyword(s):  
Gene Expression ◽  
Blood Flow ◽  
Gene Transfer ◽  
Transgene Expression ◽  
Ex Vivo ◽  
Arterial Blood Flow ◽  
Vein Grafts ◽  
Arterial Blood ◽  
En Face

Background Autogenous vein grafts are effective therapies for obstructive arterial disease. However, their long-term utility is limited by stenosis and occlusion. Genetic engineering of veins that prevents intimal hyperplasia and atherosclerosis could significantly improve the clinical utility of vein grafts. We recently reported that a helper-dependent adenoviral vector (HDAd) reduces atherosclerosis 4 wks after gene transfer in fat-fed rabbits and can express a therapeutic transgene (apo AI) in normal rabbit carotids for at least 48 wks. Use of HDAd for vein graft gene therapy will depend on achievement of similarly high and persistent transgene expression in grafted veins. Hypothesis We tested the hypothesis that Ad-mediated transgene expression in grafted veins (at an early time point) can be increased by varying the timing of gene transfer. Methods Rabbit external jugular veins were transduced by exposure to a beta galactosidase (b-gal)-expressing Ad: in situ either without (a) or with (b) immediate arterial grafting; c) ex vivo with grafting after overnight incubation with Ad; d) in vivo immediately after grafting and e) in vivo 4 wks after grafting (n = 6 - 19 veins/group). Transgene expression was measured in veins removed 3 d after Ad exposure by PCR quantitation of b-gal mRNA and by en-face planimetry of blue-stained area. Results B-gal transgene expression was higher in ungrafted veins than in veins grafted immediately after gene transfer (84 ± 17 vs 9.4 ± 2.0 arbitrary units (AU); P < 0.0001). Overnight incubation of veins with Ad increased gene expression ex vivo by 10-fold but neither this nor performing vector infusion immediately after grafting improved gene expression (11 ± 4.7 and 9.1 ± 1.8 AU; P > 0.9 for both vs immediately grafted veins). Delaying gene transfer until 4 wks after grafting significantly increased gene expression, to a level equivalent to transgene expression in ungrafted veins (61 ± 11 AU; P = 0.3 vs ungrafted veins). En face planimetry yielded similar results. Conclusions Exposure of a transduced vein to arterial blood flow is associated with significant loss of transgene expression. Transgene expression in grafted veins is significantly higher when gene transfer is performed 4 wks after exposure of the vein to arterial blood flow.

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