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Purpose To explore differences in arterial stiffness of the aorta and carotid artery, assessed by pulse wave velocity (PWV), to evaluate the blood flow volume distribution towards the carotid circulation and to assess the effect of aging on the coupling between aortic and carotid PWV using velocity-encoded magnetic resonance imaging (MRI). Materials and Methods Sixteen adult younger volunteers (age <30 years) and 16 older volunteers (age >45 years) underwent 3T MRI examination to assess aortic and carotid flow volumes and PWV using the transit time method. Results Aortic versus carotid PWV-ratio was 1.2 for younger volunteers and 0.95 for older volunteers, demonstrating leveling of wall stiffness. Furthermore, flow volume per minute in the internal carotid artery was lower for older versus younger volunteers (mean volume 177 ± 42 mL/min/m2 vs. 147 ± 32 mL/min/m2, P = 0.028), whereas aorta and common carotid artery flow volumes were not different. Consequently, the fraction of blood flow volume towards the brain was smaller for older versus younger volunteers (61 ± 9% versus 71 ± 8%, P = 0.002). Conclusion PWV-leveling between aorta and carotid artery at older age is associated with a reduction in blood flow volume towards the brain. Velocity-encoded MRI can be used to evaluate PWV and flow volume distribution in the aortic arch and the carotid circulation. J. Magn. Reson. Imaging 2014;40:287-293. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effect of spatial (ie, number of sampling locations along the aorta) and temporal sampling density on aortic pulse wave velocity (PWV) assessment from velocity-encoded MRI in patients with Marfan syndrome (MFS). Materials and Methods: Twenty-three MFS patients (12 men, mean age 36 ± 14 years) were included. Three PWV-methods were evaluated: 1) reference PWVi.p. from in-plane velocity-encoded MRI with dense temporal and spatial sampling; 2) conventional PWVt.p. from through-plane velocity-encoded MRI with dense temporal but sparse spatial sampling at three aortic locations; 3) EPI-accelerated PWVt.p. with sparse temporal but improved spatial sampling at five aortic locations with acceleration by echo-planar imaging (EPI). Results: Despite inferior temporal resolution, EPI-accelerated PWVt.p. showed stronger correlation ( r = 0.92 vs. r = 0.65, P = 0.03) with reference PWVi.p. in the total aorta, with less error (8% vs. 16%) and variation (11% vs. 27%) as compared to conventional PWVt.p.. In the aortic arch, correlation was comparable for both EPI-accelerated and conventional PWVt.p. with reference PWVi.p. ( r = 0.66 vs. r = 0.67, P = 0.46), albeit 92% scan-time reduction by EPI-acceleration. Conclusion: Improving spatial sampling density by adding two acquisition planes along the aorta results in more accurate PWV assessment, even when temporal resolution decreases. For regional PWV assessment in the aortic arch, EPI-accelerated and conventional PWV assessment are comparably accurate. Scan-time reduction makes EPI-accelerated PWV assessment the preferred method of choice. J. Magn. Reson. Imaging 2012; 36:1470-1476. © 2012 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The article presents a double-blind study on chronic heart failure (CHF) patients to determine the effects of carvedilol on plasma vascular endothelial growth factor (VEGF). It states that carvedilol or placebo were given randomly to patients, who were treated based on an uptitration schedule. Results show the benefits of beta-blockers in ischemic heart disease (IHD) and CHF. It concludes that CHF patients using carvedilol had increased VEGF.