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Background: Atrioventricular block (AVB) is rare in hyperthyroidism (HTH). Little is known about the true prevalence, clinical course, optimal management, and outcomes of different types of AVBs in patients with HTH. To address these uncertainties, we aimed to conduct a systematic review by combining the available literature to provide more meaningful data regarding AVBs in HTH. Methods: We systematically searched PubMed, Scopus, Embase, and Google Scholar for articles reporting patients who developed AVB in the context of HTH. Data were analysed in STATA 16. The main outcomes included types of AVB, frequency of pacemaker insertion, and resolution of AVB. The systematic review is registered with the International Prospective Register of Systematic Reviews (PROSPERO) with the identification number CRD42022335598. Results: A total of 56 studies (39 case reports, 12 case series, 3 conference abstracts, 1 retrospective study, and 1 prospective observational study) with 87 patients were included in the analysis, with a mean age of 39.1 ± 17.6 years. Females constituted 65.7% (n = 48) of the cohort. Complete heart block (CHB) was the most commonly reported AVB (N = 45, 51.7%), followed by first-degree AVB (16.1%) and second-degree AVB (14.9%). Overall, 21 patients underwent pacing. A permanent pacemaker was inserted in one patient with second-degree AVB and six patients with CHB. Mortality was reported in one patient with CHB. The clinical course and management of HTH and AVBs did not differ in patients with CHB or lower-degree blocks. Apart from lower rates of goitre and more use of carbimazole in those who underwent pacing, no differences were found when compared to the patients managed without pacing. Conclusion: Current data suggest that CHB is the most common type of AVB in patients with HTH. Most patients can be managed with anti-thyroid management alone. Additionally, whether pacemaker insertion alters the clinical outcomes needs further exploration. [ABSTRACT FROM AUTHOR]

In this paper, a rotated Y-shaped antenna is designed and compared in terms of performance using a conventional and EBG ground planes for future Fifth Generation (5G) cellular communication system. The rotated Y-shaped antenna is designed to transmit at 38 GHz which is one of the most prominent candidate bands for future 5G communication systems. In the design of conventional antenna and metamaterial surfaces (mushroom, slotted), Rogers-5880 substrate having relative permittivity, thickness and loss tangent of 2.2, 0.254 mm, and 0.0009 respectively have been used. The conventional rotated Y-shaped antenna offers a satisfactory wider bandwidth (0.87 GHz) at 38.06 GHz frequency band, which gets further improved using the EBG surfaces (mushroom, slotted) as a ground plane by 1.23 GHz and 0.97 GHz respectively. Similarly, the conventional 5G antenna radiates efficiently with an efficiency of 88% and is increased by using the EBG surfaces (slotted, mushroom-like) to 90% and 94% respectively at the desired resonant frequency band. The conventional antenna yields a bore side gain of 6.59 dB which is further enhanced up to 8.91dB and 7.50 dB by using mushroom-like and slotted EBG surfaces respectively as a ground plane. The proposed rotated Y-shaped antenna and EBG surfaces (mushroom, slotted) are analyzed using the Finite Integration Technique (FIT) employed in Computer Simulation Technology (CST) software. The designed antenna is applicable for future 5G applications. [ABSTRACT FROM AUTHOR]