Trans-catheter aortic valve implantation: Contemporary practice and the future

With increasing life expectancy, the epidemic of valvular heart disease, especially aortic stenosis (AS), is becoming more prevalent. Transcatheter aortic valve implantation (TAVI) has emerged as an alternative therapy for patients with significant aortic valve disease. It offers a less invasive procedure in comparison to surgical aortic valve replacement (sAVR) and an attractive substitute from the patient’s perspective. The evidence for TAVI in inoperable and high risk surgical patients is now established and in the intermediate risk group has been accumulating rapidly and is looking favourable for TAVI. However, the full ‘TAVI story’ is still unfolding. Technological advances in devices and delivery systems are evolving with the aim to improve the function and durability of TAVI and to simplify the procedure while enhancing safety. The incidence of vascular injury and pacemaker requirement post TAVI remains an issue and further development in this regard is therefore of utmost importance, particularly as lower risk and potentially younger patients are treated. Moreover, the evidence concerning long-term durability of the TAVI prostheses continues to accumulate. Whilst TAVI is proving to be an invaluable tool for inoperable and high risk patients, more trial evidence is needed before it encompases lower risk populations and moreover, its use as a first line treatment worldwide in most healthcare systems is limited by the costs associated with the prosthesis

Aortic stenosis and anemia with an update on approaches to managing angiodysplasia in 2018

Angiodyplasia and aortic stenosis are both conditions that are highly prevalent in elderly people and can often co-exist. Recent studies suggest that this association is related to subtle alterations in plasma coagulation factors. The von Willebrand factor is the strongest link between aortic stenosis and bleeding associated with gastrointestinal angiodysplasia. With an ageing population, the disease burden of aortic stenosis and its association with angiodysplasia of the bowel makes this an incredibly underdiagnosed yet important condition. Clinicians should be aware of this association when dealing with elderly patients presenting either with unexplained anemia, gastrointestinal bleeding or with aortic stenosis. A high index of suspicion and appropriate diagnostic techniques followed by appropriate and prompt treatment could be life-saving. No clear guidelines exist on management but surgical aortic valve replacement is thought to offer the best hope for long-term resolution of bleeding. With a growing number of technological armamentarium in the management of such patients, especially with the advent of transcatheter aortic valve implantation, new options can be offered even to elderly patients with comorbidities for whom conventional surgery would have been impossible

You Do Not Have to Get through This Alone: Interpersonal Emotion Regulation and Psychosocial Resources during the COVID-19 Pandemic across Four Countries

While experiencing the unpredictable events of the COVID-19 pandemic, we are likely to turn to people in order to regulate our emotions. In this research, we investigate how this interpersonal emotion regulation is connected to affective symptoms, above and beyond intrapersonal emotion regulation. Furthermore, we explore whether perceived psychosocial resources moderate these associations, i.e., if individuals reporting healthier social connections benefit differently from interpersonal emotion regulation. N = 1401 participants from the USA, UK, Germany, and Switzerland completed an online survey that included text samples. Affective symptoms (depression, adjustment disorder, fear of COVID-19) were examined based on self-reported as well as language-based indicators. As psychosocial resources, we examined social support, loneliness, attachment style, and trust. We defined latent variables for adaptive and maladaptive interpersonal emotion regulation and analyzed how they were associated with affective symptoms controlling for intrapersonal emotion regulation. Further, we analyzed how they interacted with psychosocial resources. Maladaptive interpersonal emotion regulation strategies were associated with affective symptoms. With lower psychosocial resources, the associations between interpersonal emotion regulation and depressive symptoms were more pronounced. The results highlight that maladaptive interpersonal emotion regulation is associated with worse mental health. These effects are not buffered by more psychosocial resources and are stronger for people with low psychosocial resources

Dc-MMC for the interconnection of HVDC grids with different line topologies

© 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksDC-DC converters are needed for the future development of high voltage direct current (HVDC) grids, as they allow to interconnect lines with different voltages and topologies. The dc-dc converters can increase the grid controllability adding power flow control, voltage regulation and/or fault blocking capability. The dc modular multilevel converter (dc-MMC) is a non-isolated solution proposed to interconnect HVDC systems with the same line topology. This paper proposes a new dcMMC with a control strategy, which allows the converter to interconnect different line topologies (e.g., rigid bipole connected to a symmetric monopole). The paper presents the different line topologies in HVDC installations. Then, a mathematical model with a variable transformation is proposed for the new dc-dc converter. A control structure is proposed and implemented in Matlab/Simulink using an average arm model and simplified dc grids. The results validate the control in normal operation, fault blocking capability and post-fault scenario (degraded mode).Postprint (published version

Case Study of Non-Isolated MMC DC-DC Converter in HVDC Grids

Peer reviewedPublisher PD

Vision-based measurement systems for static and dynamic characteristics of overhead lines

In the paper, optical-based measurement methods for calculating the deflection and vibration of overhead lines are presented. The authors describe the state of the art in the field of non-contact examination of static and dynamic overhead transmission line characteristics, and propose concepts of vision-based measurement systems for both static and dynamic states of a structure. The system devoted to static measurements is based on a digital SLR camera and image-processing software used for the acquisition and interpretation of data. The digital image correlation method, implemented in Wiz2D software, is applied to compute the displacement of the transmission line cable with respect to a known baseline position. Dynamic characteristics of the structure are obtained using a stereo-vision system consisting of two high-speed digital cameras. Corresponding points in two video sequences of the vibrating cable are tracked using TEMA software. 3D positions in a camera frame of reference and displacements are computed using a 3D reconstruction method. The paper describes two series of experiments conducted on a lab setup and the obtained results are examined and discussed