Cerebrovascular mental stress reactivity is impaired in hypertension

<p>Abstract</p> <p>Background</p> <p>Brachial artery reactivity in response to shear stress is altered in subjects with hypertension. Since endothelial dysfunction is generalized, we hypothesized that carotid artery (CA) reactivity would also be altered in hypertension.</p> <p>Purpose</p> <p>To compare (CA endothelium-dependent vasodilation in response to mental stress in normal and hypertensive subjects.</p> <p>Methods</p> <p>We evaluated CA reactivity to mental stress in 10 young healthy human volunteers (aged 23 ± 4 years), 20 older healthy volunteers (aged 49 ± 11 years) and in 28 patients with essential hypertension (aged 51 ± 13 years). In 10 healthy volunteers and 12 hypertensive subjects, middle cerebral artery (MCA) PW transcranial Doppler was performed before and 3 minutes after mental stress.</p> <p>Results</p> <p>Mental stress by Stroop color word conflict, math or anger recall tests caused CA vasodilation in young healthy subjects (0.61 ± 0.06 to 0.65 ± 0.07 cm, p < 0.05) and in older healthy subjects (0.63 ± 0.06 to 0.66 ± 0.07 cm, p < 0.05), whereas no CA vasodilation occurred in hypertensive subjects (0.69 ± 0.06 to 0.68 ± 0.07 cm; p, NS). CA blood flow in response to mental stress increased in young healthy subjects (419 ± 134 to 541 ± 209 ml, p < 0.01 vs. baseline) and in older healthy subjects (351 ± 114 to 454 ± 136 ml, p < 0.01 vs. baseline) whereas no change in blood flow (444 ± 143 vs. 458 ± 195 ml; p, 0.59) occurred in hypertensive subjects. There was no difference in the CA response to nitroglycerin in healthy and hypertensive subjects. Mental stress caused a significant increase in baseline to peak MCA systolic (84 ± 22 to 95 ± 22 cm/s, p < 0.05), diastolic (42 ± 12 to 49 ± 14 cm/s, p < 0.05) as well as mean (30 ± 13 to 39 ± 13 cm/s, p < 0.05) PW Doppler velocities in normal subjects, whereas no change in systolic (70 ± 18 to 73 ± 22 cm/s, p < 0.05), diastolic (34 ± 14 to 37 ± 14 cm/s, p = ns) or mean velocities (25 ± 9 to 26 ± 9 cm/s, p = ns) occurred in hypertensive subjects, despite a similar increase in heart rate and blood pressure in response to mental stress in both groups.</p> <p>Conclusion</p> <p>Mental stress produces CA vasodilation and is accompanied by an increase in CA and MCA blood flow in healthy subjects. This mental stress induced CA vasodilation and flow reserve is attenuated in subjects with hypertension and may reflect cerebral vascular endothelial dysfunction. Assessment of mental stress induced CA reactivity by ultrasound is a novel method for assessing the impact of hypertension on cerebrovascular endothelial function and blood flow reserve.</p

Usefulness of echocardiographic-fluoroscopic fusion imaging in adult structural heart disease

Percutaneous approaches to treat structural heart diseases are growing in number and complexity. Multimodality imaging is essential for planning and monitoring such interventions. The combination of three-dimensional transoesophageal echocardiography with fluoroscopy is the cornerstone of interventional imaging. However, these two modalities are displayed on separate screens, and are handled by different physicians, which requires a complex mental reconstruction for the interventional team. To overcome this issue, echocardiographic-fluoroscopic fusion imaging has been introduced recently in clinical practice. This system combines, in a single view, the precise visualization of catheter and devices provided by fluoroscopy with the continuous soft tissue information provided by echocardiography. In addition, the procedure may be guided using a marker-tracking mode. However, there are few data on how this new technology can have an impact on our routine clinical practice and patient outcomes. In this review, we provide a user manual for the system, discuss its potential clinical applications in adult structural heart diseases and consider future perspectives.Les solutions percutanées pour traiter les cardiopathies structurelles de l'adulte sont en constante augmentation mais leur complexité également. L'imagerie multimodale est indispensable pour la planification et le monitorage de ce type d'intervention. L'association de l’échocardiographie tridimensionnelle par voie œsophagienne et de la fluoroscopie constitue la pierre angulaire de l'imagerie interventionnelle. Cependant, ces deux modalités sont affichées sur des écrans séparés et sont chacune manipulées par des médecins différents, ce qui nécessite une reconstruction mentale complexe de la part de l’équipe interventionnelle. Afin de contourner ce problème, l'imagerie de fusion entre l’échocardiographie et la fluoroscopie a récemment été introduite en pratique clinique. Ce système permet de combiner sur un seul écran la précision de la fluoroscopie pour visualiser les cathéters et les dispositifs intracardiaques, à l'information tissulaire continue apportée par l’échocardiographie. De plus, la procédure peut être guidée par une fonction de marquage de zone d'intérêt. Cependant, il existe peu de données sur l'intérêt que peut avoir cette nouvelle technologie dans notre pratique clinique. Dans cette revue de la littérature, les auteurs détaillent le fonctionnement du système de fusion d'image, ses potentielles applications cliniques chez l'adulte, et les domaines qui restent à explorer

A New Three-Dimensional Echocardiography Method to Quantify Aortic Valve Calcification

Background: Aortic valve calcification (AVC) quantification is computed from multidetector computed tomography (MDCT). The aim of this study was to test the hypothesis that three-dimensional (3D) transthoracic echocardiography can be used to provide a bedside method to assess AVC. Methods: The study included 94 patients (mean age, 78 ± 12 years; mean aortic valve [AV] area, 1.0 ± 0.6 cm2) referred for MDCT and echocardiography for AV assessment. Apical 3D full-volume data sets focused on the AV region were acquired during transthoracic echocardiography, and a region-growing algorithm was applied offline to compute 3D transthoracic echocardiographic AVC (AVC-3DEcho). AVC-3DEcho was compared with AVC by MDCT and with calcium weight in the subgroup of patients referred for surgery, with explanted AVs analyzed by a pathologist (n = 22). Results: In the explanted valve group, AVC-3DEcho score exhibited fair correlations with MDCT score (r = 0.85, P &lt;.001), calcium load (r = 0.81, P &lt;.001), and peak AV velocity (r = 0.64, P &lt;.001). In the overall population, AVC-3DEcho score correlated modestly with MDCT score (r = 0.61, P &lt;.001) but had similar accuracy to identify severe aortic stenosis (area under the curve = 0.94). AVC-3DEcho &gt; 1,054 mm3 identified severe aortic stenosis with specificity of 100% and sensitivity of 76%. In addition, AVC-3DEcho was associated with the presence of significant paravalvular regurgitation after transcatheter aortic valve implantation. Finally, intraobserver and interobserver variability for AVC-3DEcho score was 4.2% and 8.9%, respectively. Conclusions: AVC-3DEcho correlated with calcium weight obtained from pathologic analysis and MDCT. These data suggest that a bedside method for quantifying AV calcification with ultrasound is feasible

Characterization of 18-Fluorodeoxyglucose Uptake Pattern in Infective Endocarditis After Transcatheter Aortic Valve Implantation

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