Mouse Heart Rate in a Human: Diagnostic Mystery of an Extreme Tachyarrhythmia

We report telemetry recording of an extreme non-fatal tachyarrhythmia noted in a hospitalized quadriplegic male with history of atrial fibrillation where the average ventricular conduction rate was found to be about 600 beats per minute and was associated with transient syncope. A medical literature review suggests that the fastest human ventricular conduction rate reported to date in a tachyarrhythmia is 480 beats per minute. We therefore report the fastest human heart rate noted in a tachyarrhythmia and the most probable mechanism of this arrhythmia being a rapid atrial fibrillation with 1:1 conduction in the setting of probable co-existing multiple bypass tracts

Hydroxychloroquine: A Comprehensive Review and Its Controversial Role in Coronavirus Disease 2019

Hydroxychloroquine, initially used as an antimalarial, is used as an immunomodulatory and anti-inflammatory agent for the management of autoimmune and rheumatic diseases such as systemic lupus erythematosus. Lately, there has been interest in its potential efficacy against severe acute respiratory syndrome coronavirus 2, with several speculated mechanisms. The purpose of this review is to elaborate on the mechanisms surrounding hydroxychloroquine. The review is an in-depth analysis of the antimalarial, immunomodulatory, and antiviral mechanisms of hydroxychloroquine, with detailed and novel pictorial explanations. The mechanisms of hydroxychloroquine are related to potential cardiotoxic manifestations and demonstrate potential adverse effects when used for coronavirus disease 2019 (COVID-19). Finally, current literature associated with hydroxychloroquine and COVID-19 has been analyzed to interrelate the mechanisms, adverse effects, and use of hydroxychloroquine in the current pandemic. Currently, there is insufficient evidence about the efficacy and safety of hydroxychloroquine in COVID-19.KEY MESSAGES HCQ, initially an antimalarial agent, is used as an immunomodulatory agent for managing several autoimmune diseases, for which its efficacy is linked to inhibiting lysosomal antigen processing, MHC-II antigen presentation, and TLR functions. HCQ is generally well-tolerated although severe life-threatening adverse effects including cardiomyopathy and conduction defects have been reported. HCQ use in COVID-19 should be discouraged outside clinical trials under strict medical supervision

Prophylactic corticosteroid use in patients receiving axicabtagene ciloleucel for large B-cell lymphoma

ZUMA-1 (NCT02348216) examined the safety and efficacy of axicabtagene ciloleucel (axi-cel), an autologous CD19-directed chimaeric antigen receptor (CAR)-T cell therapy, in refractory large B-cell lymphoma. To reduce treatment-related toxicity, several exploratory safety management cohorts were added to ZUMA-1. Specifically, cohort 6 investigated management of cytokine release syndrome (CRS) and neurologic events (NEs) with prophylactic corticosteroids and earlier corticosteroid and tocilizumab intervention. CRS and NE incidence and severity were primary end-points. Following leukapheresis, patients could receive optional bridging therapy per investigator discretion. All patients received conditioning chemotherapy (days -5 through -3), 2 × 106 CAR-T cells/kg (day 0) and once-daily oral dexamethasone [10 mg, day 0 (before axi-cel) through day 2]. Forty patients received axi-cel. CRS occurred in 80% of patients (all grade ≤2). Any grade and grade 3 or higher NEs occurred in 58% and 13% of patients respectively. Sixty-eight per cent of patients did not experience CRS or NEs within 72 h of axi-cel. With a median follow-up of 8·9 months, objective and complete response rates were 95% and 80% respectively. Overall, prophylactic corticosteroids and earlier corticosteroid and/or tocilizumab intervention resulted in no grade 3 or higher CRS, a low rate of grade 3 or higher NEs and high response rates in this study population

Voltage source converter based multi terminal DC sub-transmission system for city infeed

Distribution system has witnessed numerous problems due to concentrated power loading in cities. Stability, reliability, peak demand, poor power quality, unbalanced loading are some of the major issues besides handling of large AC networks. This paper proposes an insertion of DC power dam connected between transmission and distribution system, through bidirectional voltage source converter (VSC) both on transmission and distribution sides at multiple places, to provide the comprehensive solution to the problems of interconnected AC distribution network. A study has been done through MATLAB simulation and results are presented for solutions to problems witnessed by the Distribution system. A new simplified current control technique is also presented for realization of simulation model of the system

Control of VSC based multi-terminal DC system for support to critical loads on grid side witnessing loss of generation

Often in a networked AC system, substation witnessing loss of generation fails to supply the loads, which are sensitive and critical. Creation of dedicated infrastructure for support is quite costly. The paper proposes to augment a Multi-Terminal Medium Voltage DC Sub-Transmission System (MT-MVDCS) between the AC grid and AC distribution system, to enhance unlimited expansion, selection of power input, availability, stability and reliability at low cost. The control algorithm of the proposed system is discussed for control power flow, decoupled power control to input only real power from the mains, supply desired reactive power and cater to the critical load connected to the grid side witnessing the loss of generation. The indirect current control is utilized to control the Voltage Source Converters (VSC) under grid tied conditions, whereas, the VSCs are PWM controlled when supplying power to passive loads. The controller in later case regulates the AC side voltage by tight control on modulation index, and evenly compensates voltage drop on DC bus through injection of third harmonic component. Simulation based results demonstrate that proposed method provides effective control of VSC both in current controlled mode and voltage controlled mode for the aforesaid objectives. The presented results show that seamless power is provided to the critical loads connected to the grid with loss/failure of generation, without any transients in voltage

Role of high-frequency USG in rotator cuff injury and its comparison with MRI

Introduction: Rotator cuff injury is one of the common causes of long-term shoulder pain and disability encountered in the orthopedic clinic. The spectrum of rotator cuff injury includes tendonitis, partial tears, and complete tears. They also may influence the development of the degenerative disease of glenohumeral joint and rotator cuff arthropathy. Material and Methods: The present, prospective study entitled “Role of high-frequency USG in rotator cuff injury and its comparison with MRI” was conducted in the Department of Radiodiagnosis on a total of 100 patients who presented with signs and symptoms of shoulder joint injury in Department of Orthopedic who were then referred for USG and MRI examination to the Department of Radiodiagnosis. Result: Mean age of the patients was 38.26±14.51 years and the majority of patients belonged to the 3rd decade (34%). About 7% of patients belonged to the 2nd decade, 18% of patients each belonged to the 4th and 5th decades of age group. Only 8% and 7% of patients in the present study belonged to extremes of age i.e. >60 years and <20 years respectively. Conclusion: Based on the findings of the present study, it is concluded that rotator cuff injuries are commonly encountered conditions in routine practice, and males are commonly affected as compared to females

Machine Learning Prediction of Death in Critically Ill Patients With Coronavirus Disease 2019.

OBJECTIVES: Critically ill patients with coronavirus disease 2019 have variable mortality. Risk scores could improve care and be used for prognostic enrichment in trials. We aimed to compare machine learning algorithms and develop a simple tool for predicting 28-day mortality in ICU patients with coronavirus disease 2019. DESIGN: This was an observational study of adult patients with coronavirus disease 2019. The primary outcome was 28-day inhospital mortality. Machine learning models and a simple tool were derived using variables from the first 48 hours of ICU admission and validated externally in independent sites and temporally with more recent admissions. Models were compared with a modified Sequential Organ Failure Assessment score, National Early Warning Score, and CURB-65 using the area under the receiver operating characteristic curve and calibration. SETTING: Sixty-eight U.S. ICUs. PATIENTS: Adults with coronavirus disease 2019 admitted to 68 ICUs in the United States between March 4, 2020, and June 29, 2020. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The study included 5,075 patients, 1,846 (36.4%) of whom died by day 28. eXtreme Gradient Boosting had the highest area under the receiver operating characteristic curve in external validation (0.81) and was well-calibrated, while k-nearest neighbors were the lowest performing machine learning algorithm (area under the receiver operating characteristic curve 0.69). Findings were similar with temporal validation. The simple tool, which was created using the most important features from the eXtreme Gradient Boosting model, had a significantly higher area under the receiver operating characteristic curve in external validation (0.78) than the Sequential Organ Failure Assessment score (0.69), National Early Warning Score (0.60), and CURB-65 (0.65; p < 0.05 for all comparisons). Age, number of ICU beds, creatinine, lactate, arterial pH, and Pao2/Fio2 ratio were the most important predictors in the eXtreme Gradient Boosting model. CONCLUSIONS: eXtreme Gradient Boosting had the highest discrimination overall, and our simple tool had higher discrimination than a modified Sequential Organ Failure Assessment score, National Early Warning Score, and CURB-65 on external validation. These models could be used to improve triage decisions and clinical trial enrichment