<p>The increase in indications for cardiac implantable devices had led to an increase in the number of device implantations worldwide, with a corresponding increase in the incidence of complications. Finally, in 1980, the development of methods for removing problematic leads and devices were first attempted. Currently, an average of 10,000–15,000 extractions/year are performed worldwide. Improving the design and technical performance of device leads has been the goal of several scientific and engineering efforts; however, they occasionally continue to fail, potentially leading to adverse clinical outcomes. The preferred technique is transvenous lead extraction, and over the past few decades, its effectiveness has substantially improved. Nevertheless, the extraction procedure is associated with high risks, and these risks should be considered when deciding on the procedure. The present review discusses the issues associated with determining appropriate strategies to reduce the risks associated with lead extraction and identifying accurate indicators for the removal of cardiac implantable device leads.</p><p>Received 17 May 2019. Revised 12 December 2019. Accepted 13 December 2019.</p><p><strong>Funding:</strong> The study did not have sponsorship.</p><p><strong>Conflict of interest:</strong> Authors declare no conflict of interest.</p>
The results of 3D modeling in the Comsol Multiphysics software environment and calculation of temperature and thermal deformation fields of GaAs crystals of monolithic integrated circuits (MIS) of microwave amplifiers as part of the submodule of the X-band output power amplifier (VUM) and their contact connections with the substrate in pulse modes of operation with different duty cycles are presented. It is shown that the maximum temperature and thermomechanical stresses in the MIS crystal in the dynamic mode of operation significantly exceed the calculated values for the stationary mode and strongly depend on the pulse duty cycle of the power dissipated by the MIS. Thermomechanical stresses take the maximum value in some narrow region near the boundary of the adhesive connection of the MIS crystal with the mounting plate; this maximum value strongly depends on the temperature coefficient of expansion (TCR) of the adhesive and takes the lowest value when the TCR of the adhesive is equal to the TCR of the GaAs crystal.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.