Coronary Computed Tomography Angiography Based Assessment of Endothelial Shear Stress and Its Association with Atherosclerotic Plaque Distribution In-Vivo

Purpose The relationship between low endothelial shear stress (ESS) and coronary atherosclerosis is well established. ESS assessment so far depended on invasive procedures. The aim of this study was to demonstrate the relationship between ESS and coronary atherosclerosis by using non-invasive coronary computed tomography angiography (CTA) for computational fluid dynamics (CFD) simulations. Methods A total number of 7 consecutive patients with suspected coronary artery disease who received CTA and invasive angiography with IVUS analysis were included in this study. CTA examinations were performed using a dual-source scanner. These datasets were used to build a 3D mesh model. CFD calculations were performed using a validated CFD solver. The presence of plaque was assumed if the thickness of the intima-media complex exceeded 0.3 mm in IVUS. Plaque composition was derived by IVUS radiofrequency data analysis. Results Plaque was present in 32.1% of all analyzed cross-sections. Plaque prevalence was highest in areas of low ESS (49.6%) and high ESS (34.8%). In parts exposed to intermediate-low and intermediate-high ESS few plaques were found (20.0% and 24.0%) (p<0.001). Wall thickness was closely associated with local ESS. Intima-media thickness was 0.43 +/- 0.34mm in low and 0.38 +/- 0.32mm in high ESS segments. It was significantly lower when the arterial wall was exposed to intermediate ESS (0.25 +/- 0.18mm and 0.28 +/- 0.20mm) (p<0.001). Fibrofatty tissue was predominately found in areas exposed to low ESS (p <= 0.023). Conclusions In this study a close association of atherosclerotic plaque distribution and ESS pattern could be demonstrated in-vivo. Adding CFD analysis to coronary CTA offers the possibility to gather morphologic and physiologic data within one non-invasive examination

A Test of the Effect of Denominational Schools in Romania

Studies in sociology of education in recent decades have consistently found an advantage for students in denominational schools - those with religious subordination - in terms of educational performance, compared with those in secular schools. Although in Romania a large part of the students from pre-university education attend confessional schools this advantage has not been investigated for the Romanian case. Taking advantage of the increased validity of the Romanian baccalaureate exam, following the measures from 2011-2012 and the availability of the statistical data regarding the schools in Oradea (Bihor county), we checked whether the hypothesis of such an advantage is confirmed in the Romanian case. Applying bivariate analyzes by type of schools (secular vs. confessional) and by types of tracks of the net pass rates (from the total of the graduates) we find that, although the promotion rates are higher for denominational schools, the support for the hypothesis of an advantage of denominational schools is fragile as much of the difference can be attributed to the academic orientation of denominational schools and to the fact that they succeed, probably, in selecting students with better educational skills

Wall thickness.

<p>Mean wall thickness was highest in quartile 1 (low endothelial shear stress (ESS)) and lowest in quartiles 2 and 3 (intermediate ESS). Vessel wall thickness in quartile 4 (high ESS) was in between. Differences were not significant between quartile 2 and 3 (p = 0.15). All other differences were statistically significant (p < 0.001).</p><p>SD: standard deviation</p><p>Wall thickness.</p

Color encoded illustration of endothelial shear stress (ESS) on a 3D model of a right coronary artery obtained by coronary computed tomography angiography.

<p>After segmentation side branches were cut 1–2 cm from the branching point. The volume mesh consisted of about 400,000 polyhedral cells. The Navier-Stokes equations were solved by the finite element method. The level of ESS increases from blue to red as shown in the color map on the left.</p

Distribution of plaque tissue composition in areas exposed to different levels of endothelial shear stress (ESS).

<p>Panel (A) shows an example of an early, panel (B) an example of a more advanced atherosclerotic lesion as assessed by intravascular ultrasound radiofrequency data analysis. Fibrous tissue is represented by dark green, fibrofatty tissue by light green, necrotic tissue by red and calcified tissue by white colour. We observed a significantly higher amount of fibrofatty (*) tissue in areas exposed to the lowest level of ESS (quartile 1) in comparison to low-intermediate ESS (quartile 2), intermediate-high ESS (quartile 3) or high ESS (quartile 4) (p≤0.023) (C). There was no difference in the amount of other tissue types depending on the level of ESS (p≥0.061).</p

Benefit of Contact Force Sensing Catheter Technology for Successful Left Atrial Anterior Line Formation: A Prospective Randomized Trial

Introduction. The value of contact force information for ablation of LA anterior line is unknown. In a prospective randomized clinical trial, we investigated if information on contact force during left atrial (LA) anterior line ablation reduces total radiofrequency time and results in higher rates of bidirectional line block in patients undergoing pulmonary vein isolation (PVI) plus substrate modification. Methods. We included patients with indication for pulmonary vein isolation (PVI) and additional substrate modification. For LA anterior line ablation, patients were randomized to contact force information visible (n=35) or blinded (n=37). Patients received contrast enhanced cardiac magnetic resonance imaging (cMRI) before and 3-6 months after ablation to visualize the LA anterior line. Primary endpoint was radiofrequency time to achieve bidirectional line block. Secondary endpoints were completeness of the LA anterior line on cMRI, distribution of contact force, procedural data, adverse events, and 12 months success rate. Results. In 72 patients (64±9 years, 68% male), bidirectional LA anterior line block was achieved in 70 (97%) patients. Radiofrequency time to bidirectional block did not differ significantly across groups (contact force information visible 23±18min versus contact force information blinded 21±15min, p=0.50). The LA anterior line was discernable on cMRI in 40 patients (82%) without significant differences across randomization groups (p=0.46). No difference in applied contact force was found depending on cMRI line visibility. Twelve-month success and adverse event rates were comparable across groups. Conclusion. Information on contact force does not significantly improve the ablation of LA anterior lines. Clinical Trial Registration. The trial was registered at http://www.clinicaltrials.gov by identifier: NCT02217657

Course of early neurologic symptom severity after endovascular treatment of anterior circulation large vessel occlusion stroke: association with baseline multiparametric CT imaging and clinical parameters

Background: Neurologic symptom severity and deterioration at 24 hours (h) predict long-term outcomes in patients with acute large vessel occlusion (LVO) stroke of the anterior circulation. We aimed to examine the association of baseline multiparametric CT imaging and clinical factors with the course of neurologic symptom severity in the first 24 h after endovascular treatment (EVT). Methods: Patients with LVO stroke of the anterior circulation were selected from a prospectively acquired consecutive cohort of patients who underwent multiparametric CT, including non-contrast CT, CT angiography and CT perfusion before EVT. The symptom severity was assessed on admission and after 24 h using the 42-point National Institutes of Health Stroke Scale (NIHSS). Clinical and imaging data were compared between patients with and without early neurological deterioration (END). END was defined as an increase in ≥4 points, and a significant clinical improvement as a decrease in ≥4 points, compared to NIHSS on admission. Multivariate regression analyses were used to determine independent associations of imaging and clinical parameters with NIHSS score increase or decrease in the first 24 h. Results: A total of 211 patients were included, of whom 38 (18.0%) had an END. END was significantly associated with occlusion of the internal carotid artery (odds ratio (OR), 4.25; 95% CI, 1.90–9.47) and the carotid T (OR, 6.34; 95% CI, 2.56–15.71), clot burden score (OR, 0.79; 95% CI, 0.68–0.92) and total ischemic volume (OR, 1.01; 95% CI, 1.00–1.01). In a comprehensive multivariate analysis model including periprocedural parameters and complications after EVT, carotid T occlusion remained independently associated with END, next to reperfusion status and intracranial hemorrhage. Favorable reperfusion status and small ischemic core volume were associated with clinical improvement after 24 h. Conclusions: The use of imaging parameters as a surrogate for early NIHSS progression in an acute LVO stroke after EVT reached limited performance with only carotid T occlusion as an independent predictor of END. Reperfusion status and early complications in terms of intracranial hemorrhage are critical factors that influence patient outcome in the acute stroke phase after EVT

Transcatheter Aortic Valve Replacement with the Self-Expandable Core Valve Evolut Prosthesis Using the Cusp-Overlap vs. Tricusp-View

Despite the rapid increase in experience and technological improvement, the incidence of conduction disturbances in patients undergoing transcatheter aortic valve replacement (TAVR) with the self-expandable CoreValve Evolut valve remains high. Recently, a cusp-overlap view (COP) implantation technique has been proposed for TAVR with self-expandable valves offering an improved visualization during valve expansion compared to the three-cusp view (TCV). This study aims to systematically analyze procedural outcomes of TAVR patients treated with the CoreValve Evolut valve using a COP compared to TCV in a high-volume center. The primary endpoint was technical success according the 2021 VARC-3 criteria. A total of 122 consecutive patients (61 pts. TCV: April 2019 to November 2020; 61 pts. COP: December 2020 to October 2021) that underwent TAVR with the CoreValve Evolut prosthesis were included in this analysis. Although there was no difference in the primary endpoint technical success between TCV and COP patients (93.4% vs. 90.2%, OR 0.65, 95% CI 0.16, 2.4, p = 0.51), we observed a significantly lower risk for permanent pacemaker implantation (PPI) among COP patients (TCV: 27.9% vs. COP: 13.1%, OR 0.39, 95% CI 0.15, 0.97, p = 0.047). Implantation of the CoreValve Evolut prosthesis using the COP might help to reduce the rate of PPI following TAVR