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71.

Background

Information on young patients with Brugada syndrome (BrS) and arrhythmic events (AEs) is limited.

Objectives

The purpose of this study was to describe their characteristics and management as well as risk factors for AE recurrence.

Methods

A total of 57 patients (age ≤20 years), all with BrS and AEs, were divided into pediatric (age ≤12 years; n = 26) and adolescents (age 13 to 20 years; n = 31).

Results

Patients’ median age at time of first AE was 14 years, with a majority of males (74%), Caucasians (70%), and probands (79%) who presented as aborted cardiac arrest (84%). A significant proportion of patients (28%) exhibited fever-related AE. Family history of sudden cardiac death (SCD), prior syncope, spontaneous type 1 Brugada electrocardiogram (ECG), inducible ventricular fibrillation at electrophysiological study, and SCN5A mutations were present in 26%, 49%, 65%, 28%, and 58% of patients, respectively. The pediatric group differed from the adolescents, with a greater proportion of females, Caucasians, fever-related AEs, and spontaneous type-1 ECG. During follow-up, 68% of pediatric and 64% of adolescents had recurrent AE, with median time of 9.9 and 27.0 months, respectively. Approximately one-third of recurrent AEs occurred on quinidine therapy, and among the pediatric group, 60% of recurrent AEs were fever-related. Risk factors for recurrent AE included sinus node dysfunction, atrial arrhythmias, intraventricular conduction delay, or large S-wave on ECG lead I in the pediatric group and the presence of SCN5A mutation among adolescents.

Conclusions

Young BrS patients with AE represent a very arrhythmogenic group. Current management after first arrhythmia episode is associated with high recurrence rate. Alternative therapies, besides defibrillator implantation, should be considered.  相似文献   
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BackgroundGait event detection of the initial contact and toe off is essential for running gait analysis, allowing the derivation of parameters such as stance time. Heuristic-based methods exist to estimate these key gait events from tibial accelerometry. However, these methods are tailored to very specific acceleration profiles, which may offer complications when dealing with larger data sets and inherent biological variability.Research questionCan a structured machine learning approach achieve a more accurate prediction of running gait event timings from tibial accelerometry, compared to the previously utilised heuristic approaches?MethodsForce-based event detection acted as the criterion measure in order to assess the accuracy, repeatability and sensitivity of the predicted gait events. 3D tibial acceleration and ground reaction force data from 93 rearfoot runners were captured. A heuristic method and two structured machine learning methods were employed to derive initial contact, toe off and stance time from tibial acceleration signals.ResultsBoth a structured perceptron model (median absolute error of stance time estimation: 10.00 ± 8.73 ms) and a structured recurrent neural network model (median absolute error of stance time estimation: 6.50 ± 5.74 ms) significantly outperformed the existing heuristic approach (median absolute error of stance time estimation: 11.25 ± 9.52 ms). Thus, results indicate that a structured recurrent neural network machine learning model offers the most accurate and consistent estimation of the gait events and its derived stance time during level overground running.SignificanceThe machine learning methods seem less affected by intra- and inter-subject variation within the data, allowing for accurate and efficient automated data output during rearfoot overground running. Furthermore offering possibilities for real-time monitoring and biofeedback during prolonged measurements, even outside the laboratory.  相似文献   
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PurposeTo compare the technical success of antegrade uteral stent (AUS) and retrograde ureteral stent (RUS) placements in patients with malignant ureteral obstruction (MUO) and to determine the predictors of technical failure of RUS.Materials and MethodsThis study retrospectively included 61 AUS placements (44 patients) performed under fluoroscopic guidance and 76 RUS placements (55 patients) performed under cystoscopic guidance in patients with MUO from January 2019 to December 2020. Technical success rates of the 2 techniques were compared using inverse probability of treatment weighting (IPTW) analysis. Logistic regression was used to identify predictive factors for technical failures.ResultsTechnical success was achieved in 98.4% of the AUS group and 47.4% of the RUS group. After stabilized IPTW, the technical success rate was higher in the AUS group than in the RUS group (adjusted risk difference, 49.4%; 95% confidence interval [CI], 35.4%–63.1%). The independent predictors for technical failure of the RUS procedure were age of ≥65 years (odds ratio [OR], 5.56; 95% CI, 1.73–21.27), ureteral orifice invasion (OR, 4.21; 95% CI, 1.46–13.46), and extrinsic cancer (OR, 15.58; 95% CI, 2.92–111.81).ConclusionsThe technical success rate of AUS placement was higher than that of RUS placement in patients with MUO. RUS failure was associated with age of ≥65 years, cancer with ureteral orifice invasion, and extrinsic ureteral obstruction.  相似文献   
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《Vaccine》2015,33(27):3110-3113
BackgroundIn October 2012, the Advisory Committee on Immunization Practices (ACIP) recommended a dose of tetanus toxoid, reduced diphtheria toxoid, and acellular pertussis (Tdap) during each pregnancy, irrespective of the woman's prior history of receiving Tdap. A retrospective cohort study to assess the safety of Tdap vaccination in pregnant women in two Vaccine Safety Datalink (VSD) sites during 2010–2012 found a small but statistically significant increased risk of chorioamnionitis.ObjectiveWe conducted a review of the VAERS database to describe reports of chorioamnionitis following receipt of any vaccines.MethodsWe searched the VAERS database for reports of chorioamnionitis after any vaccine in the United States during the period from July 1, 1990 through February 2, 2014.ResultsVAERS received 31 reports of chorioamnionitis out of 3389 pregnancy reports in 24 years. The three most common vaccines in these reports were 2009 H1N1 inactivated influenza, quadrivalent human papillomavirus (HPV4), and Tdap vaccines in 32%, 29% and 26% of reports, respectively. Fifty-eight percent of reports had at least one reported risk factor for chorioamnionitis. Chorioamnionitis was identified in 3 reports of spontaneous abortions and 6 stillbirths, 6 reports of preterm birth (two of whom died) and 16 reports of term birth; maternal outcomes included two reports of postpartum hemorrhage and one report of maternal admission to the intensive care unit. No maternal deaths were reported.ConclusionChorioamnionitis was found to be uncommonly reported, representing 1% of pregnancy reports to VAERS. A majority of reports had at least one risk factor for chorioamnionitis.  相似文献   
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BackgroundLong-term cardiovascular and limb outcomes after revascularization for peripheral artery disease and, in particular, prognosis after post-procedure major adverse limb events (MALE) are not well-studied.ObjectivesThis study sought to describe outcomes after peripheral revascularization and assess relationships between post-procedure MALE hospitalization and subsequent events.MethodsPatients undergoing peripheral artery revascularization between January 1, 2009, and September 30, 2015, in the Premier Healthcare Database were examined for the co-primary outcomes of interest, composite myocardial infarction (MI) or stroke and composite major amputation or peripheral revascularization. Multivariable adjusted Cox proportional hazards models with post-procedure MALE hospitalization included as a time-dependent covariate were developed to estimate hazard ratios for outcomes.ResultsAmong 393,017 revascularized patients followed for a median of 2.7 years (interquartile range: 1.3 to 4.4 years), the cumulative incidence of MI or stroke was 9.8% and that of major amputation or peripheral revascularization was 41.9%. A total of 50,750 patients (12.9%) had at least 1 post-procedure MALE hospitalization. In time-dependent covariate adjusted models, post-procedure MALE hospitalization was associated with greater risk of subsequent MI or stroke (hazard ratio: 1.34; 95% confidence interval: 1.28 to 1.40) and major amputation or peripheral revascularization (hazard ratio: 8.13; 95% confidence interval: 7.96 to 8.29). After peripheral revascularization with or without post-procedure MALE hospitalization, risk of limb events increased rapidly post-procedure and more slowly after the first year, whereas cardiac risk increased steadily during follow-up.ConclusionsRevascularized peripheral artery disease patients face earlier limb and later cardiovascular ischemic risk that is heightened among patients with post-procedure MALE hospitalization. Increased provider awareness of these long-term risks may guide efforts to improve post-procedural outcomes.  相似文献   
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