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Juan Carlos Diaz

and 13 more

Background: Transvenous lead extraction (TLE) is standard of care for the management of patients with cardiac implantable electronic device infection or lead related complications. Currently, objective data on TLE in Latin America is lacking. Objective: To describe the current practice standards in Latin American centers performing TLE. Methods: An online survey was sent through the mailing list of the Latin American Heart Rhythm Association (LAHRS). Online reminders were sent through the mailing list; duplicate answers were discarded. The survey was available for one month, after which no more answers were accepted. Results: A total of 48 answers were received, from 44 different institutions (39.6% from Colombia, 27,1% from Brazil), with most respondents (83%) being electrophysiologists. Twenty-nine institutions (66%) performed less than 10 lead extractions/year, with 7 (15%) institutions not performing lead extraction. Although most institutions in which lead extraction is performed reported using several tools, mechanical rotating sheaths were cited as the main tool (73%), 13.5% reported the use of mechanical extraction sheaths and only 13.5% reporting the use of laser sheaths. Management of infected leads was performed according to current guidelines. Conclusion: This survey is the first attempt to provide information on TLE procedures in Latin America and could provide useful information for future prospective registries. According to our results, the number of centers performing high volume lead extraction in Latin America is smaller than that reported in other continents, with most interventions performed using mechanical tools. Future prospective registries assessing acute and long-term success are needed.

Asad Aboud

and 8 more

Introduction Programmed electrical stimulation is an essential part of VT ablation procedures but VT is not always inducible, usually for reasons that are not clear. We sought to review pacing site-specific failure of programmed electrical stimulation (PES) to induce scar-related ventricular tachycardia (VT). Methods A series of patients in whom aggressive programmed stimulation from traditional RV pacing sites failed to induce VT, but VT was easily inducible from a non-traditional site are reviewed. Computer simulations in a simple 2-dimensional model of reentry were performed. Results Six patients who had no inducible sustained VT from the RV apex/outflow tract with at least 3 extrastimuli, but relatively easily induced VT from the LV, basal RV, epicardium, or atrium are described. In 5 of these patients, the site that induced VT was closer to the likely reentry circuit region based on mapping and ablation. Computer simulations illustrated that the spatial relation between the pacing site and the entrance and exits of a reentry isthmus can determine the ease of initiation of reentry by determining the time available for recovery of excitability at the initial region of block. Conclusions The site of PES has a marked effect on inducibility of VT in some patients such that PES from the RV apex and outflow regions will fail to expose clinically relevant VTs. The frequency with which this occurs is not certain. Stimulation from alternative sites is a reasonable consideration in selected patients.

Xiangnian Li

and 4 more

Background: Temporary cardiac pacing is frequently required during heart surgery due to life-threatening complications of arrhythmias. The conventional method of epicardial pacing could have risks such as bleeding and myocardial tears. Transvenous endocardial pacing provides another option. The efficiency of transvenous epicardial and endocardial pacing were compared in this study. Methods: We performed a retrospective study and reviewed medical records in patients who received either thoracoscopic cardiac surgery with transvenous endocardial pacing or median sternotomy with transvenous epicardial pacing between June 2019 and January 2021. Patients were assigned into two groups depending on the surgical type and pacing method. Preoperative patient characteristics and perioperative outcomes were collected. The efficiencies of endocardial and epicardial pacing were compared and analyzed in SPSS. Results: A total of 68 patients were included. Thirty-five (51.5%) patients were in the thoracoscopic cardiac surgery group with transvenous endocardial pacing. Thirty-three (48.5%) patients were in the median sternotomy group with transvenous epicardial pacing. Intensive care unit (ICU) time (p = 0.014), in-hospital duration (p = 0.036), operation time (p = 0.005), and the 24-h drainage volume (p < 0.001) showed significant differences between the two groups. There was no significant difference between the pre- and post-operative heart rate and rhythm compared between two groups. Conclusions: Compared with transvenous epicardial pacing, transvenous endocardial pacing showed no significant differences in heart rate and arrhythmia during the perioperative period. Transvenous endocardial pacing was also associated with better operative measurements.

Feng Li

and 4 more

Backgroud The long-term outcomes of this combined procedure remain elusive. This meta-analysis aimed to assess the long-term efficacy and safety of combined procedure. Methods PubMed, Embase, Cochrane Library, and Web of Science were systematically searched from the establishment of databases to 1 January 2021. Studies on the long-term (defined as a mean follow-up of approximately 12 months or longer) efficacy and safety outcomes of combined ablation and LAAC were included for meta-analysis. Results A total of 16 studies comprising 1,428 patients were included in the meta-analysis. The pooled long term freedom rate from atrial arrhythmia was 0.66 (95% confidence interval [CI], 0.59-0.71), long-term successful rate sealing of LAAC was 1.00 (95% CI, 1.00-1.00), and ischemic stroke/transient ischemic attack/systemic embolism during follow-up was 0.01 (95% CI, 0.00-0.02). Meanwhile, the rates of peri-procedural adverse events included phrenic nerve palsy, intracoronary air embolus, device embolization, peri-procedural death of 0.00 (95% CI, 0.00-0.00), procedure-related bleeding events of 0.03 (95% CI, 0.02-0.04), and pericardial effusion requiring or not requiring intervention of 0.00 (95% CI, 0.00-0.01). Moreover, the rates of long-term adverse events rate included device dislocation, intracranial bleeding, and pericardial effusion requiring or not requiring intervention, and all-cause mortality of 0.00 (95% CI, 0.00-0.00), device embolization of 0.01 (95% CI, 0.00-0.01), and other bleeding events of 0.01 (95% CI, 0.00-0.03). Conclusion This meta-analysis suggests that the strategy of combined atrial ablation and LAAC is effective and safe during long-term follow-up

Stephen Williams

and 1 more

Objectives As we pass the anniversary of the declaration of a global pandemic by the World Health Organisation, it invites us to reflect upon the inescapable changes that coronavirus has wrought upon ENT and, in particular, rhinological practice. As it remains unclear when we will globally emerge from the shadow of COVID-19, a critical analysis of the evidence base on both the assessment and mitigation of risk is vital for ENT departments worldwide. This article presents a systematic review of the literature examining articles which consider either the quantification of risk or strategies to mitigate risk specifically in the setting of rhinological surgery. Design Systematic literature review. Results The literature search yielded a total of 3406 returns with 24 articles meeting eligibility criteria. A narrative synthesis stratified results into two broad themes: those which made an assessment as to the aerosolisation of droplets during sinus surgery, further subdivided into work which considered macroscopically visible droplets and that which considered smaller particles, and those studies which examined the mitigation of this risk. Conclusion Studies considering the aerosolisation of both droplets and smaller particles suggest endonasal surgery carries significant risk. Whilst results both highlight a range of innovative adjunctive strategies and support suction as an important variable to reduce aerosolisation, appropriate use of personal protective equipment (PPE) should be considered mandatory for all healthcare professionals involved in rhinological surgery given studies have demonstrated that close adherence to PPE use is effective at preventing COVID-19 infection.
Adoptive cell immunotherapy with chimeric antigen receptor (CAR) T cell has brought a revolutionary means of treatment for aggressive diseases such as hematologic malignancies and solid tumors. Over the last decade, FDA approved three types of CAR-T cells against CD19 hematologic malignancies, including Tisagenlecleucel (Kymriah), Axicabtagene ciloleucel (Yescarta), and Brexucabtagene autoleucel (Tecartus). Despite outstanding results gained from different clinical trials, CAR-T cell therapy is not free from side effects and toxicities, and needs careful investigations and improvements. Gene-editing technology, clustered regularly interspaced short palindromic repeats (CRISPR)/ CRISPR-associated protein 9 (Cas9) system has emerged as a promising tool to address some of the CAR-T therapy hurdles. Using CRISPR/Cas9 technology, CAR expression as well as other cellular pathways can be modified in various ways to enhance CAR-T cell’s anti-tumor function and persistence in immunosuppressive tumor microenvironment. CRISPR/Cas9 technology can also be utilized to reduce CAR-T cells toxicity and side effects. Hereby, we discuss the practical challenges and hurdles related to the accuracy, efficiency, efficacy, safety and delivery of CRISPR/Cas9 technology to the genetically engineered-T cells. Combining of these two state-of-the-art technologies, CRISPR/Cas9 and CAR-T cells, the field of oncology has an extraordinary opportunity to enter a new era of immunotherapy, which offers novel therapeutic options for different types of tumors.

Mahmut Tanırlar

and 4 more

Background Diabetic neuropathy is a complication seen in diabetic patients and involves motor, sensory or autonomic nerve fibres due to minor vessel damage. Aims This study was planned to determine the knowledge and awareness levels of physicians working in family health centres about diabetic neuropathy and their approach to diabetic neuropathy. Methodology Our study is a cross-sectional descriptive study conducted in 111 family health centres in Denizli. The data were obtained by face to face questionnaire method. Results Of the 219 people participating in the study, 70.8% (n = 155) were male and 6.8% (n = 15) were family medicine specialists. 52.5% (n = 115) of the participants allocated 6-10 minutes of examination time to diabetes mellitus patients, 77.6% (n = 170) did not receive diabetic neuropathy training after graduation, and 44.3% (n = 97) ) had not previously diagnosed any patient with diabetic neuropathy. 74.4% of the participants (n = 163) stated that they did not use any diabetic neuropathy diagnosis and screening tests in their daily practice. 31% (n = 68) of the participants stated that their level of knowledge on diabetic neuropathy was either poor or very poor. 45.7% of the participants (n = 100) thought diabetic neuropathy screening, diagnosis, treatment and follow-up could be made in primary care. 89.5% (n = 196) of the participants stated that they needed training on diabetic neuropathy. Those who rely on their knowledge and clinical experience in diagnosing, monitoring and treating diabetic neuropathy were 44.3% of the participants (n = 97). Conclusion Although diabetic neuropathy is one of the most critical complications of diabetes mellitus, there is a severe insufficiency in postgraduate education in primary health care services. Simple tests and methods for physicians working in primary care should be included in the daily polyclinic routine.

Bingbin Xie

and 5 more

Objective: To investigate the symptomatic relief and functional preservation of a novel surgical strategy combined with triple semicircular canal occlusion and endolymphatic sac decompression in patients with intractable Meniere’s disease. Design: Retrospective analysis. Setting: Patients with intractable Meniere’s disease in the Department of Otolaryngology Head & Neck in the Second Affiliated Hospital of Nanchang University between July 2015 and June 2019. Participants: Data from 46 patients diagnosed with Meniere’s disease, and underwent surgery Methods: Triple semicircular canal occlusion combined with endolymphatic sac decompression was performed in all patients with intractable Meniere’s disease. Pre- and postoperative vertigo attacks, hearing levels, tinnitus, aural fullness, and equilibrium function rehabilitation were analyzed at defined time points during follow-up. Results: A significant vertigo control rate was observed in all patients postoperatively. The overall control rate of vertigo postoperatively was 100% in the entire follow-up, with a complete control rate of 97.8% and a substantial control rate of 2.2%. The rate of hearing preservation was 54.35%, and all patients suffering from hearing deterioration were at stages III and IV. The rate of tinnitus and aural fullness alleviation was 65.8% and 100%, respectively. Four patients failed to regain the equilibrium function postoperatively. Conclusion: Combining triple semicircular canal occlusion with endolymphatic sac decompression is an efficient strategy for vertigo control in patients with intractable Meniere’s disease. Patients in advanced stages suffered more from hearing function deterioration. Hearing preservation and tinnitus alleviation warrant further investigation.

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Mohammed Al-Sadawi

and 7 more

Abstract: Background: This meta-analysis assessed the relationship between Obstructive Sleep Apnea (OSA) and echocardiographic parameters of diastolic dysfunction (DD), which are used in the assessment of Heart Failure with Preserved Ejection Fraction (HFpEF). Methods: We searched the databases including Ovid MEDLINE, Ovid Embase Scopus, Web of Science, Google Scholar, and EBSCO CINAHL from inception up to December 26th, 2020. The search was not restricted to time, publication status or language. Comparisons were made between patients with OSA, diagnosed in-laboratory polysomnography (PSG) or home sleep apnea testing (HSAT), and patients without OSA in relation to established markers of diastolic dysfunction. Results: Primary search identified 2512 studies. A total of 18 studies including 2509 participants were included. The two groups were free of conventional cardiovascular risk factors. Significant structural changes were observed between the two groups. Patients with OSA exhibited greater LAVI (3.94 CI [0.8, 7.07]; p=0.000) and left ventricular mass index (11.10 CI [2.56,19.65]; p=0.000) as compared to control group. The presence of OSA was also associated with more prolonged DT (10.44 ms CI [0.71,20.16]; p=0.04), IVRT (7.85 ms CI[4.48, 11.22]; p=0.000), and lower E/A ratio (-0.62 CI [-1,-0.24]; p=0.001) suggestive of early DD. The E/e’ ratio (0.94 CI[0.44, 1.45]; p=0.000) was increased. Conclusion: An association between OSA and echocardiographic parameters of DD was detected that was independent of conventional cardiovascular risk factors. OSA may be independently associated with DD perhaps due to higher LV mass. Investigating the role of CPAP therapy in reversing or ameliorating diastolic dysfunction is recommended.

Gunter Sturm

and 38 more

Background: There is controversy whether taking β-blockers or ACE inhibitors (ACEI) is a risk factor for more severe systemic insect sting reactions (SSR) and whether it increases the number or severity of adverse events (AE) during venom immunotherapy (VIT). Methods: In this open, prospective, observational, multicenter trial, we recruited patients with a history of a SSR and indication for VIT. The primary objective of this study was to evaluate whether patients taking β-blockers or ACEI show more systemic AE during VIT compared to patients without such treatment. Results: In total, 1,425 patients were enrolled and VIT was performed in 1,342 patients. Of all patients included, 388 (27.2%) took antihypertensive (AHT) drugs (10.4% took β-blockers, 11.9% ACEI, 5.0% β-blockers and ACEI). Only 5.6% of patients under AHT treatment experienced systemic AE during VIT as compared with 7.4% of patients without these drugs (OR: 0.74, 95% CI: 0.43–1.22, p=0.25). The severity of the initial sting reaction was not affected by the intake of β-blockers or ACEI (OR: 1.14, 95% CI: 0.89–1.46, p=0.29). In total, 210 (17.7%) patients were re-stung during VIT and 191 (91.0%) tolerated the sting without systemic symptoms. Of the 19 patients with VIT treatment failure, 4 took β-blockers, none an ACEI. Conclusions: This trial provides robust evidence that taking β-blockers or ACEI does neither increase the frequency of systemic AE during VIT nor aggravate SSR. Moreover, results suggest that these drugs do not impair effectiveness of VIT. (Funded by Medical University of Graz, Austria; number, NCT04269629)

Nazanin Kermani

and 12 more

Background. Patients with severe asthma may have a greater risk of dying from COVID-19 disease. Angiotensin converting enzyme-2 (ACE2) and the enzyme proteases, transmembrane protease serine 2 (TMPRSS2) and FURIN, are needed for viral attachment and invasion into host cells. Methods. We examined microarray mRNA expression of ACE2, TMPRSS2 and FURIN in sputum, bronchial brushing and bronchial biopsies of the European U-BIOPRED cohort. Clinical parameters and molecular phenotypes, including asthma severity, sputum inflammatory cells, lung functions, oral corticosteroid (OCS) use, and transcriptomic-associated clusters, were examined in relation to gene expression levels. Results. ACE2 levels were significantly increased in sputum of severe asthma compared to mild-moderate asthma. In multivariate analyses, sputum ACE2 levels were positively associated with OCS use and male gender. Sputum FURIN levels were significantly related to neutrophils (%) and the presence of severe asthma. In bronchial brushing samples, TMPRSS2 levels were positively associated with male gender and body mass index, whereas FURIN levels with male gender and blood neutrophils. In bronchial biopsies, TMPRSS2 levels were positively related to blood neutrophils. The neutrophilic molecular phenotype characterised by high inflammasome activation expressed significantly higher FURIN levels in sputum than the eosinophilic Type 2-high or the pauci-granulocytic oxidative phosphorylation phenotypes. Conclusion. Levels of ACE2 and FURIN may differ by clinical or molecular phenotypes of asthma. Sputum FURIN expression levels were strongly associated with neutrophilic inflammation and with inflammasome activation. This might indicate the potential for a greater morbidity and mortality outcome from SARS-CoV-2 infection in neutrophilic severe asthma.

Mehmet Pehlivaoğlu

and 5 more

Aim: This study evaluated the effect of intracavitary levobupivacaine infusion diluted with locally applied isotonic solution for pain control in cystoscopy. Methods: Included in this study are 100 patients who had previously undergone transurethral tumor resection for bladder tumor and were followed up by cystoscopy. The patients were randomized into five groups (n = 20). In the first, second, third, and fourth groups, 4, 6, 8, and 10 mL of levobupivacaine HCl (5.0 mg/mL) were mixed with 26, 24, 22, and 20 mL of isotonic solution, respectively. Hence, the total mixture was 30 mL for each group. The fifth group was the control group. In this group, the standard method commonly used in most clinics was utilized. That is, a gel containing Cathejell-2% lidocaine (25 mg lidocaine) was applied. Cystoscopic interventions were performed with a 17.5 Fr rigid cystoscope and 0°, 30°, and 70° lens. During cystoscopy and 30 min later, the pain status of patients was assessed using the Visual Analogue Scale (VAS), and patient satisfaction was questioned. Results: The mean VAS score during and after the cystoscopy procedure was significantly lower in the levobupivacaine groups compared to the lidocaine group. In addition, patient satisfaction in the levobupivacaine groups was significantly higher than in the lidocaine group. No drug-related side-effects were observed in all groups. Conclusion: Thus, levobupivacaine is a more effective drug than lidocaine alone to control pain during cystoscopy. The use of levobupivacaine is recommended to prevent possible complications of general anesthesia by eliminating the need for the aforementioned as well as its cost-saving advantage.

Yanhui Dong

and 4 more

Groundwater age is often used to estimate groundwater recharge through a simplified analytical approach. This estimated recharge is thought to be representative of the mean recharge between the point of entry and the sampling point. However, given the complexity in actual recharge, whether the mean recharge is reasonable is still unclear. This study examined the validity of the method to estimate long-term average groundwater recharge and the possibility of obtaining reasonable spatial recharge pattern. We first validated our model in producing reasonable age distributions using a constant flux boundary condition. We then generated different flow fields and age patterns by using various spatially-varying flux boundary conditions with different magnitudes and wavelengths. Groundwater recharge was estimated and analyzed afterwards using the method at the spatial scale. We illustrated the main findings with a field example in the end. Our results suggest that we can estimate long-term average groundwater recharge with 10% error in many parts of an aquifer. The size of these areas decreases with the increase in both the amplitude and the wavelength. The chance of obtaining a reasonable groundwater recharge is higher if an age sample is collected from the middle of an aquifer and at downstream areas. Our study also indicates that the method can also be used to estimate local groundwater recharge if age samples are collected close to the water table. However, care must be taken to determine groundwater age regardless of conditions.

Xinyi Guan

and 4 more

Adriana Bustamante

and 3 more

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