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Carotid plaque vulnerability features beyond the degree of stenosis may play a key role in the pathogenesis and recurrence of ischemic cerebrovascular events. This study sought to compare intraplaque hemorrhage (IPH) as a marker of plaque vulnerability in symptomatic patients with mild ( We included patients who experienced ischemic cerebrovascular events with no other identifiable sources and underwent carotid endarterectomy for mild (n=32), moderate (n=47), and severe (n=58) carotid artery stenosis. The degree of stenosis and imaging hallmarks were assessed by computed tomography angiography or magnetic resonance angiography. Plaque specimens were stained with hematoxylin and eosin and Movat pentachrome staining. Carotid plaques of patients with mild stenosis had a higher extent of IPH (%) on tissue analysis compared with patients with moderate (mild, 15.7% [interquartile range, 7.8%–26.7%]; moderate, 3.9% [0.0%–9.2%]; P P P Our major finding is the association of IPH with mild carotid artery stenosis based on histological analysis. The current study may suggest that IPH potentially plays a role in the mechanism of stroke in patients with nonobstructive carotid stenosis.

In order to understand the irregular flow conditions of blood in a locally constricted blood vessel, analytical results are obtained for a porous effect on oscillatory blood flow that acts as a Newtonian flow. Compared to the radius of the unconstricted tube, the surface roughness is presumed to be cosine-shaped and the maximum height of the roughness is very small. The main focus of investigation of the porous effect on oscillatory arterial blood flow with mild stenosis, a mathematical model has been developed.

Arterial stenosis is an abnormal condition in arteries due to the deposition of fats and other substances, called atherosclerosis. As it restricts the blood flow, it may induce a heart attack. Employing the Navier-Stokes equations, we consider the blood flow in an artery with the presence of a stenosis in an axisymmetric shape. We analyze the blood flow dynamics in cylindrical form by evaluating pressure, pressure drop against the wall, shear stress on the wall. We also analyze the dynamics by evaluating the ratio of pressure drop with stenosis to the pressure drop without stenosis against the wall, and the ratio of maximum to minimum shear stresses with the ratios of various thicknesses of stenosis to radius of the artery.

A 52-year-old man, with a history of allergic rhinitis and without coronary risk factors, transferred to our hospital because of cardiac arrest. Coronary angiography revealed no significant stenosis in left coronary arteries ([Figure 1A][1]), and mild stenosis in right coronary artery ([Figure 1B

As the degree of luminal narrowing increases, shear stress increases, and high shear stress is known to activate platelets. However, the relationship between the degree of luminal narrowing and the composition of thrombus in patients with plaque erosion has not been studied. A total of 148 patients with plaque erosion and thrombus detected by optical coherence tomography were divided into tertiles based on the minimum lumen area (MLA) at the culprit lesion. Thrombus was categorized as platelet-rich or fibrin-rich. Among 148 patients, 50 (34%) were in the mild stenosis group, 49 (33%) were in the moderate stenosis group, and 49 (33%) were in the severe stenosis group. The composition of thrombus was significantly different among the 3 groups (prevalence of platelet-rich thrombus was 60% in the mild stenosis group; 78% in the moderate stenosis group; and 84% in the severe stenosis group; P = 0.021). The pattern of fibrin-rich thrombus showed the opposite: 40%, 22%, and 16%, respectively. In the multivariate analysis, current smoking was independently associated with fibrin-rich thrombus (odds ratio [OR] 2.364 [95% CI 1.004–5.567], P = 0.049). This study demonstrated that platelet-rich thrombus was the predominant type of thrombus in plaque erosion. The prevalence of fibrin-rich thrombus was highest in the mild stenosis group.

MHD peristaltic transport of copper-water nanofluid in an artery with mild stenosis for different shapes of nanoparticles is studied in this paper. The exact solution is obtained for velocity, temperature and pressure gradient. The influence of all the parameters on velocity, temperature and pressure gradient is observed. The effect of stenosis plays a vital role in this paper, as it finds its application in the field of medicine. It is observed that the nanofluid flows rapidly in the presence of stenosis, which helps in destroying of the stencils soon. The shape of the nanoparticle is another important point to be concentrated due to based on the shape of the nanoparticle the fluid flow depends. The shape of the nanoparticle should be considered as bricks to increase the velocity, temperature and the pressure gradient. But a reversed behavior is observed if the shape of the nanoparticle is chosen as platelets. Streamlines are also concentrated and it is observed that there are more number of boluses if the shape of the nanoparticle is chosen as bricks. The effect of volume of the solid nanoparticle and stenosis warrants further study of the flow of nanofluids in tube and channel.

Objective Measurement of the degree of stenosis is not enough to decide on the treatment strategy for patients with carotid stenosis. Plaque morphology examination is needed for such a decision-making. Thus, we evaluated the usefulness of plaque magnetic resonance imaging (MRI) to decide on the modality of treatment for patients with carotid atherosclerotic plaques. Materials and Methods Fifteen patients presenting with carotid stenosis between 2014 and 2016 were included. They underwent angiography for measurement of the degree of stenosis. Carotid plaques were visualized using MRI. Results There were six (40%) stable and nine (60%) unstable plaques. Seven symptomatic patients (77.7%) had unstable lesions and two symptomatic patients (33.3%) had stable lesions (p = 0.096). There were six (40%) intraplaque hemorrhage (IPH) cases. There were six symptomatic patients (100%) in the IPH group and three symptomatic patients (33.3%) in the non-IPH group (p = 0.013). The mean stenosis degree was 58.9% in the IPH group and 70.4% in the non-IPH group (p = 0.094). Symptoms occurred irrespective of the degree of the stenosis in the IPH groups. In the IPH group, the recurrent ischemic cerebrovascular event rate was 33.3%. Particularly, the recurrent ischemic cerebrovascular event rate was 66.7% in the IPH group with mild stenosis treated with medications. Conclusion IPH in plaque MRI is significantly associated with ischemic symptoms and has a high risk for subsequent ischemic cerebrovascular events irrespective of the degree of stenosis. Plaque MRI is a useful tool in predicting symptomatic risks for carotid stenosis irrespective of the degree of such stenosis.

Objectives This study sought to obtain in vivo data to confirm assumptions on device loading conditions and assess procedural feasibility, safety, and valve performance. Background The Harmony transcatheter pulmonary valve (Medtronic, Minneapolis, Minnesota) was designed for patients with severe pulmonary regurgitation who require pulmonary valve replacement. Methods Three sites participated in this first Food and Drug Administration–approved early feasibility study using an innovative device design to accommodate the complex anatomy of the right ventricular outflow tract. Potentially eligible patients underwent review by a screening committee to determine implant eligibility. Six-month outcomes are reported. Results Between May 2013 and May 2015, 66 subjects were enrolled, and 21 were approved for implant and underwent catheterization; 20 were implanted. Catheterized patients had a median age of 25 years, were predominantly diagnosed with tetralogy of Fallot (95%), had severe pulmonary regurgitation (95%), and had trivial or mild stenosis. The device was delivered in the desired location in 19 of 20 (95%) patients. Proximal migration occurred in 1 patient during delivery system removal. Two devices were surgically explanted. Premature ventricular contractions related to the procedure were reported in 3 patients; 2 were resolved without treatment. One patient had ventricular arrhythmias that required treatment and later were resolved. At 1 month, echocardiography revealed none or trivial pulmonary regurgitation in all and a mean right ventricular outflow tract gradient of 16 ± 8 mm Hg (range 6 to 31 mm Hg). Conclusions In this feasibility study of the Harmony transcatheter pulmonary valve device, there was high procedural success and safety, and favorable acute device performance.

We report the case of a young boy with a history of total occlusion of the superior caval vein, diagnosed early after complex neonatal cardiac surgery, who developed severe protein-losing enteropathy. Protein-losing enteropathy was precipitated by a relatively mild stenosis at the junction of the inferior caval vein with the right atrium. Percutaneous stent dilation of the veno-atrial junction definitively relieved the stenosis, and the protein-losing enteropathy subsequently resolved.

Mitral valve construction using decellularized bovine pericardium is a new procedure. A 10-month-old infant with neonatal Marfan syndrome underwent mitral valve replacement due to severe mitral regurgitation with a cylinder valve constructed from decellularized bovine pericardium. Nineteen months postoperatively the patient is clinically well with trivial mitral regurgitation, mild stenosis, and without need for anticoagulation.

This paper aims at presenting numerical solutions for steady MHD blood flow through a bifurcated artery with mild stenosis in parent lumen with heat transfer assuming blood as couple stress fluid. The arteries design of bifurcation is referred to be symmetric about the axis of the artery and straight cylinders of limited length. The governing equations are non-dimensionalized and coordinate transformation is used to convert the irregular boundary to a well defined boundary. The resulting system of equations is solved numerically using the finite difference method. The variation of shear stress, flow rate and impedance near the flow divider with relevant physical parameters are presented graphically.

Supplemental Digital Content is available in the text., Background— Patients with nonobstructive coronary artery disease (NOCAD; wall irregularities, stenosis

ObjectiveThe majority of acute coronary syndromes occur in the absence of obstructive coronary artery disease (CAD), and the underlying biobehavioral processes are not well understood. Depressive symptoms and anxiety are predictive of prognosis, and have been associated with markers of inflammation that play a role in atherosclerosis. This study examines whether depressive symptoms and anxiety are associated with higher levels of high-sensitive C-reactive protein (hs-CRP) and fibrinogen in patients with non-obstructive CAD.MethodsPatients with non-obstructive CAD (“wall irregularities”, stenosis < 60%, N = 414, mean age 62.1 ± 9.3 years, 52% women) in the TweeSteden Mild Stenosis (TWIST) observational cohort study completed the Hospital Anxiety and Depression Scale (HADS). Blood samples were analyzed for hs-CRP and fibrinogen. The cross-sectional association of anxiety and depressive symptoms with hs-CRP and fibrinogen, adjusting for covariates, was examined by multivariate regression analysis.ResultsDepressive symptoms were positively associated with hs-CRP level (β = .135, p = .009), but not fibrinogen (β = .075, p = .153), adjusted for age and sex. Additional adjustments for sociodemographic, disease severity and lifestyle factors rendered the association non-significant. In the fully adjusted model, depressive symptoms were not associated with hs-CRP (β = .036, p > 0.10) and BMI was the only variable that was independently associated with hs-CRP (β = .203, p < .001). No associations were observed for anxiety with either hs-CRP or fibrinogen (p > 0.10).ConclusionAmong patients with non-obstructive CAD, depressive symptoms and anxiety were not independently associated with hs-CRP and fibrinogen.Keywords: Non-obstructive coronary artery disease, Depression, Anxiety, hs-CRP, Fibrinogen, BMI, Lifestyle

Heat and mass transfer effects on Newtonian biomagnetic fluid of blood flow through a tapered porous artery with a stenosis is investigated. Governing equations have been modeled by treating blood as Newtonian biomagnetic fluid. The governing equations are simplified under the assumption of mild stenosis. Exact solutions have been evaluated for velocity, temperature, and concentration profiles. The effects of Newtonian nature of blood on velocity, temperature, concentration profile, wall shear stress, shearing stress at the stenosis throat and impedance of the artery are discussed graphically. Stream lines have been presented in last section of the article.

One hundred patients with infrarenal abdominal aortic aneurysms were treated by surgery. Fifteen deaths occurred postoperatively. Eleven patients died during the follow-up of a medium period of 13 months. Three patients with a ruptured aneurysm died intraoperatively before the graft was implanted. Three patients were lost to follow-up. Sixty-four patients were examined with colour-coded Duplex sonography after surgical repair. Colour-coded Duplex sonography was able to image the aortic prostheses with the adjacent major vessels. Fifty-eight patients showed a normal prosthesis, 3 dilatation proximal of the prosthesis, 1 dilatation distal of the prosthesis, 1 mild stenosis, 1 haematoma. Colour-coded Duplex sonography imaged the intraluminal space of the prosthesis more easily than ultrasound. Colour-coded Duplex sonography was able to differentiate between intraluminal and extraluminal lesions.

Essentials A consensus methodology for assessing the effects of antiplatelet agents has not been established. Measuring platelet thrombus formation (PTF) for evaluating antiplatelet effects was assessed. PTF differentially reflected antiplatelet effects compared to other tests. PTF may be associated with the severity of carotid or intracranial arterial stenosis. Click to hear a presentation on platelet function testing in the clinic by Gresele and colleagues SummaryBackground A consensus methodology for assessing the effects of antiplatelet agents has not been established. Objective We investigated the usefulness of directly measuring platelet thrombus formation (PTF) using a microchip-based flow chamber system for evaluating antiplatelet therapy. Patients/Methods Platelet thrombus formation in the whole blood of 94 patients with ischemic cerebrovascular disease treated with clopidogrel and/or aspirin was measured in a flow chamber system at a shear rate of 1500 s−1 and was compared with the results of assays for agonist-induced platelet aggregability, phosphorylation of vasodilator-stimulated phosphoprotein, platelet p-selectin expression (PS), and platelet-monocyte complexes. Results In all patients tested, area under the flow pressure curve (AUC10), which represents platelet thrombogenicity, showed weak correlation with platelet aggregation induced by either adenosine diphosphate or collagen. In addition, AUC10 was lower in patients treated with dual antiplatelet therapy (median 79.4) compared with patients treated with aspirin or clopidogrel alone (217.7 and 301.0, respectively), whereas the parameters evaluated by the other assays did not reflect the combined treatment efficacy. In clopidogrel monotherapy patients, AUC10 was associated with the severity of arterial stenosis (R2 = 0.127, β = 1.25), and AUC10 and PS were higher in patients with severe carotid or intracranial arterial stenosis than in those with mild stenosis. Conclusions Platelet thrombus formation measurement using a flow-chamber system was useful for evaluating the efficacy of treatment with aspirin and clopidogrel, both alone and in combination. The present findings indicate that high residual platelet thrombogenicity in patients treated with clopidogrel may be associated with the severity of carotid or intracranial arterial stenosis.

Background The ratio of peak to mean pressure decrease is a new measure of transaortic continuous waveform shape that could be useful for grading aortic stenosis. Methods We retrospectively analyzed echocardiograms in 163 patients with all grades of aortic stenosis as assessed by the continuity equation. Results The peak to mean pressure decrease ratio was 1.75 (0.14) in mild stenosis, 1.66 (0.13) in moderate stenosis, 1.56 (0.10) in severe stenosis, and 1.57 (0.07) in severe aortic stenosis with left ventricular ejection fraction less than 40%. Receiver operating characteristic curve analysis showed that a threshold of less than 1.50 gave a specificity of 94% against continuity area whereas a ratio less than 1.75 gave a sensitivity of 96%. Conclusion The peak to mean pressure decrease ratio is a simple and quick cue to the likelihood of severe aortic stenosis in patients with low left ventricular ejection fraction when transaortic pressure decreases appear only moderate.

(Echocardiography 2014;31:E98–E100)Key words: Melody valve, tricuspid valve, transesophageal echocardiography, intra-cardiac echocardi-ography, three-dimensional echocardiographyA 5-year-old male, weighing 16.1 kg, with adiagnosis of interrupted aortic arch (IAA) type Band a large ventricular septal defect (VSD) pre-sented with severe bioprosthetic tricuspid valveregurgitation and mild stenosis. His medical his-tory was significant for IAA repair and main pul-monary artery (MPA) banding in the neonatalperiod. He had a significant residual coarctationand thus was taken back at 4 months of agefor Gore-tex patch aortoplasty. At 10 months ofage, he underwent VSD closure and MPA de-banding. This operation was complicated bycomplete heart block and an epicardial pace-maker system was placed. He subsequentlydeveloped a flailed tricuspid valve leaflet thatwas unable to be repaired; therefore, a 19-mmaortic tissue valve was placed in the tricuspidposition at 18 months of age. This valve even-tually became incompetent and a 23-mm aortictissue valve was placed in the tricuspid positionat 26 months of age. Follow-up echocardio-grams over time revealed worsening tricuspidregurgitation. Clinically, he had decreasingexercise tolerance despite being treated withdigoxin, enalapril, furosemide, and spironolac-tone. It was felt that alleviating his tricuspidregurgitation would improve his symptoms;therefore, he was referred for possible percuta-neous correction of his tricuspid valve regurgita-tion.In the catheterization laboratory, an 8 Frenchintra-cardiac echocardiography (ICE) catheterwas inserted into the right femoral vein (Acuso-nAcuNav, Siemens, Mountain View, CA, USA).Transesophageal echocardiographic (TEE) 2Dand 3D images (iE33; Philips, Amsterdam, The

The mechanism for the onset of chronic alcoholic pancre-atitis(CAP) involves many unresolved questions. We (1,2) have succeeded in creating an animal model of CAPby inducing mild stenosis of the pancreatic duct in experi-mentalanimals given alcohol. The CAP seen in this modelis akin to that seen in humans. This means that pancreaticduct-related factors play an important role in the onset ofCAP.

The present work deals with the theoretical study of the unsteady blood flow of a Williamson fluid through composite stenosed arteries with permeable walls. The highly non-linear momentum equations of the Williamson fluid model are simplified by considering the mild stenosis case and the perturbation solutions are evaluated. The expressions for velocity, flow impedance, wall shear stress and shearing stress at the stenosis throat are computed and discussed through graphs for different physical parameters of interest.

PURPOSE To determine 3-D time of flight MR angiography for evaluation of fibromuscular dysplasia in cervical vessels. MATERIAL AND METHODS In 386 selective angiograms of cervical vessels fibromuscular dysplasia was revealed in 4 female patients in the age of 30-54 years. FMD was located in the carotid artery (n = 5) and in the vertebral artery (n = 2) with a total of 8 lesions. RESULTS 6/8 of the lesions of the seven cervical vessels were located typically in the mid cervical portion of the vessels and 2/6 lesions were located in the atlas loop of the vertebral artery. 4 lesions showed moderate stenosis and 4 vessels showed only mild stenosis. These patterns which demonstrated the typical morphology of fibromuscular dysplasia with alternating irregular zones of widening and narrowing were evaluated well with MR angiography, the others were missed. CONCLUSION MR angiography is suitable for detection of fibromuscular dysplasia when the characteristic pattern is combined with moderate stenosis of the vessel. Conventional angiography remains the standard of reference.

An attempt has been made to investigate the non-Newtonian behaviour on blood flow through artery with mild stenosis using Hershel-Bulkley fluid model. It has been shown that the resistance to flow and wall shear stress increases with the size of stenosis, but these increases is comparatively small due to non-Newtonian behaviour of the blood.

R 2 ∗ S 3 E Bilateral intravenous contrast injection CT images of he chest demonstrated mild stenosis of the left sublavian vein and multiple deep and superficial chest all collaterals. Some normally present veins were also nlarged [1], but no clinical signs of these collaterals r SVC syndrome were apparent, as is often the case 2]. Volume rendered 3D reconstructions (Fig. 1 and Video ) beautifully delineate a rich anastamotic network, not ormally appreciated on CT. In particular, the presence of eins that run alongside named arteries such as the lateral horacic and thoracodorsal is noted. Such findings should rompt close inspection for impaired venous return of a arger vessel.

The foreskins of phimosis in children have been retracted as much as possible at the out-patient clinic, to avoid unnecessary operations. Five-hundred and twenty-seven cases of phimosis were experienced since 1986, and 427 of them were classified into 6 types according to the appearance of the penis and preputial orifice; type I (burried penis, 22 cases), type II (bottle neck, 86), type III (pinhole, 60), type IV (moderate stenosis, 154), type V (mild stenosis, 101), and type VI (scarred stenosis, 4). The foreskins were unable to retract in 13 cases (59.1%) of type I, 17 cases (19.8%) of type II, and 2 cases (50%) of type VI. In all cases of pinhole type, which looked highly stenotic, the foreskins were retractable. As a result, operation was performed only in 32 cases (6.1%) of all cases. Our best effort to retract the foreskin has reduced the operative indications of phimosis markedly.

Flow in the trachea is essential to be properly understood since it is the inlet to the lungs. Disturbance to this flow will disrupt the inlet conditions to both bronchi. In this study, disturbance of flow due to mild stenosis is investigated via numerical models. The effect of various stenosis sizes, at the middle of the trachea, to the flow pattern is studied and analyzed. 3D simplified trachea models were used and different flow conditions were applied. The results show two stages of pressure drop behavior appear as the size of the stenosis reaches fifty percent of the airway size. The inlet condition to the bronchi is also significantly disturbed as the stenosis reaches fifty percent.