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Background: In cardiac resynchronisation therapy (CRT), the coronary venous system is used for left ventricular pacing electrode placement. Despite the well- -known anatomy of the coronary sinus and its tributaries, heart failure patients’ remodelled and enlarged left ventricles may impede the successful lead placement because of acquired anatomical obstacles. Materials and methods: Fifty-five patients qualified for CRT treatment were divided into ischaemic and non-ischaemic cardiomyopathy. Forty-four control groups without heart failure underwent dual-source computed tomography (CT). Rendered reconstructions of cardiac coronary systems were compared. Results: The presence of main tributaries was comparable in all groups. The left marginal vein, small cardiac vein, and oblique vein of the left atrium were present in 63%, 60%, and 51% of the hearts in all the groups. CRT referred CTs had significantly longer distances between posterior and lateral cardiac veins over the left ventricle (p < 0.05), wider angles of tributaries (p = 0.03), and smaller lumen of coronary sinus (p = 0.03). In the non-ischaemic group, the posterior interventricular and great cardiac veins are more extensive than in the control group. Age-related analysis of vessel size shows a moderate correlation between age and diminishing mean vessel size in all the groups studied. Conclusions: The general structure of the coronary heart system is consistent in patients with and without heart failure. The variance of the general structure, or the presence of adequate veins, is an individual variation. The use of CT and analysis of the coronary veins allow better planning of the CRT-D implantation procedure and may reduce the risk of ineffective left ventricular electrode implantation. [ABSTRACT FROM AUTHOR]

Background: Although radiofrequency ablation of the cavotricuspid isthmus (CTI), responsible for sustaining atrial flutter, is a highly effective procedure, in extended patients' observations following this procedure, more than every tenth becomes unsuccessful. Therefore, this study aimed to provide helpful information about the anatomy of the CTI in transthoracic echocardiography, which can aid in better planning of the CTI radiofrequency ablation in patients with typical atrial flutter., Materials and Methods: 56 patients with typical atrial flutter after radiofrequency ablation were evaluated at the end of the 24-month observation period. With substernal modified transthoracic echocardiographic (mTTE) evaluation, we identified four main anatomical obstacles impeding radiofrequency ablation. These obstacles were tricuspid annular plane systolic excursion, cavotricuspid isthmus length, cavotricuspid isthmus morphology, and the presence of a prominent Eustachian ridge/Eustachian valve. All intraprocedural radiofrequency ablation data were collected for analysis and correlated with anatomical data., Results: In the 24-month observation period, freedom from atrial flutter was 67.86%. The mean length of the isthmus was 30.34 ± 6.67 mm. The isthmus morphology in 56 patients was categorized as flat (n = 27; 48.2%), concave (n = 10; 17.85%), and pouch (n = 19, 33.9%). A prominent Eustachian ridge was observed in 23 patients (41.1%). Lack of anatomical obstacles in mTTE evaluation resulted in 100% efficacy, while the presence of at least two obstacles significantly increased the risk of unsuccessful ablation with more than two (OR 12.31 p = 0.01). Generally, 8 mm electrodes were the most effective for non-difficult CTI, while 3.5 mm electrodes used with a 3D system had highest performance for complex CTI. Notably, aging was the only factor that worsened the long-term outcome (OR 1.07 p = 0.044)., Conclusions: Preoperative usage of mTTE evaluation helps predict difficulty in cavotricuspid isthmus radiofrequency ablation, thus allowing better planning of the radiofrequency ablation strategy using the most accurate radiofrequency ablation electrode.

Introduction: Single atrial stimulation (AAI) has been commonly used for permanent pacing in sick sinus syndrome and significant bradycardia., Objective: The study aimed to evaluate long‑term AAI pacing and to identify timing and reasons for pacing mode change., Patients and Methods: Retrospectively, we included 207 patients (60% women) with initial AAI pacing, who were followed‑up for an average of 12 years., Results: At the time of death or loss to follow‑up, 71 patients (34.3%) had unchanged AAI pacing mode. The reason for an upgrade of the pacing system was development of atrial fibrillation (AF) in 43 patients (20.78%) and atrioventricular block (AVB) in 34 patients (16.4%). The cumulative ratio for a pacemaker upgrade reoperation reached 2.77 per 100 patient‑years of the follow‑up. Cumulative ventricular pacing below 10% after an upgrade to dual‑chamber pacemaker was observed in 28.6% of the patients. Younger age at implant was the leading independent predictor of the change to dual‑chamber simulation (hazard ratio, 1.98; 95% CI, 1.976-1.988; P = 0.001). There were 11 (5%) lead malfunctions that required reoperation. Subclavian vein occlusion was noted in 9 upgrade procedures (11%). One cardiac device-related infection was observed., Conclusions: The reliability of AAI pacing decreases with each year of observation due to development of AF and AVB. However, in the current era of effective AF treatment, the advantages of AAI pacemakers, such as lower incidence of lead malfunction, venous occlusion, and infection, as compared with dual-chamber pacemakers, may make AAI pacemakers a viable option.

Non-native pests, climate change, and their interactions are likely to alter relationships between trees and tree-associated organisms with consequences for forest health. To understand and predict such changes, factors structuring tree-associated communities need to be determined. Here, we analysed the data consisting of records of insects and fungi collected from dormant twigs from 155 tree species at 51 botanical gardens or arboreta in 32 countries. Generalized dissimilarity models revealed similar relative importance of studied climatic, host-related and geographic factors on differences in tree-associated communities. Mean annual temperature, phylogenetic distance between hosts and geographic distance between locations were the major drivers of dissimilarities. The increasing importance of high temperatures on differences in studied communities indicate that climate change could affect tree-associated organisms directly and indirectly through host range shifts. Insect and fungal communities were more similar between closely related vs. distant hosts suggesting that host range shifts may facilitate the emergence of new pests. Moreover, dissimilarities among tree-associated communities increased with geographic distance indicating that human-mediated transport may serve as a pathway of the introductions of new pests. The results of this study highlight the need to limit the establishment of tree pests and increase the resilience of forest ecosystems to changes in climate., (© 2023. The Author(s).)

International trade in plants and climate change are two of the main factors causing damaging tree pests (i.e. fungi and insects) to spread into new areas. To mitigate these risks, a large-scale assessment of tree-associated fungi and insects is needed. We present records of endophytic fungi and insects in twigs of 17 angiosperm and gymnosperm genera, from 51 locations in 32 countries worldwide. Endophytic fungi were characterized by high-throughput sequencing of 352 samples from 145 tree species in 28 countries. Insects were reared from 227 samples of 109 tree species in 18 countries and sorted into taxonomic orders and feeding guilds. Herbivorous insects were grouped into morphospecies and were identified using molecular and morphological approaches. This dataset reveals the diversity of tree-associated taxa, as it contains 12,721 fungal Amplicon Sequence Variants and 208 herbivorous insect morphospecies, sampled across broad geographic and climatic gradients and for many tree species. This dataset will facilitate applied and fundamental studies on the distribution of fungal endophytes and insects in trees., (© 2022. The Author(s).)

Atrial flutter (AFL) is one of the most common arrhythmias present in clinical practice, both for the GPs and cardiologist practice. After atrial fibrillation (AF) is second the most common supraventricular arrhythmia. This usually occurs along the cavo-tricuspid isthmus of the right atrium though atrial flutter can originate from the left atrium as well. As AFL is rarely susceptible to pharmacotherapy, that is why, the guidelines of the European and American Cardiology Societies suggest non-pharmacological treatment - an ablation, which is a "gold standard". Due to the reentrant nature of atrial flutter, it is often possible to ablate the circuit that causes atrial flutter with radiofrequency catheter ablation. Catheter ablation is considered to be a first-line treatment method for many people with typical atrial flutter due to its high rate of success (>90%) and low incidence of complications. This is done in the cardiac electrophysiology lab by causing a ridge of scar tissue in the cavo-tricuspid isthmus that crosses the path of the circuit that causes atrial flutter. Eliminating conduction through the isthmus prevents reentry, and if successful, prevents the recurrence of the atrial flutter. Atrial fibrillation often occurs after catheter ablation for atrial flutter. We present an up to date overview of the most important information about AFL based on the available literature., (© 2020 MEDPRESS.)

Purpose: Mouthguards are commonly used in the prevention of head and mouth injuries in many sport disciplines. Elastic polymeric materials used in their fabrication absorb the energy of impact. However, decontamination procedures may cause damage to their surface causing deterioration of their properties and favouring pathogen colonization. The aim of the study was to determine the impact of different cleaning methods on mouthguard materials, surface quality., Methods: The material for the research consisted of 81 samples made from polymeric materials used for custom mouthguard fabrication - Impak, Corflex Orthodontic and Erkoflex. Samples were viewed under a scanning electron microscope after exposure to different cleaning methods., Results: Statistical analysis of tested decontamination procedures and disinfecting agents showed statistically important ( p < 0.05) results for the presence of small and big separated pieces, grooves and holes. Out of all the cases the lowest indicator for occurrence was in the disinfecting spray - Aftermat., Conclusions: Considering the importance of the surface material of the mouthguard, disinfection should be the method of choice for maintaining its hygiene. Impak material samples, cleaned with the Aftermat spray, showed the lowest range of damage.