Safety and acute performance of paroxysmal and early persistent atrial fibrillation ablation using temperature-controlled, very high power, short duration catheter with a new radiofrequency generator

Funding Acknowledgements

Type of funding sources: Private company. Main funding source(s): Biosense Webster Inc.

Background/Introduction

The temperature-controlled contact force radiofrequency (RF) ablation catheter (QDM) has 6 thermocouples to maintain target catheter tip temperature and 3 tip microelectrodes for high local signal resolution. It has an enhanced irrigation profile to reduce char formation. Three prospective multicenter trials demonstrated safety and effectiveness of the QDM catheter using very high-power, short duration (vHPSD; 90W/4s), conventional power (CP; ≤50W) or combined modes. These studies were performed with an older RF generator. A new generator was developed to support the full suite of legacy, temperature controlled and multichannel ablation catheters, but has not yet been formally tested in a clinical setting.

Purpose

Evaluate safety and acute performance of the QDM catheter with the new 90W-enabled generator.

Methods

This prospective, multicenter study (4 Canadian sites) used vHPSD as primary mode for Pulmonary Vein (PV) isolation with overlapping 3mm lesion tags for anterior, inferior and roof of left atrium. Adjacent, non-overlapping lesions were used posteriorly to avoid esophageal heating. CP mode was used at operator discretion for thicker atrial tissue, touch ups, and non-PV triggers (Figure). Primary endpoint was confirmed entrance block in all PVs after adenosine and/or isoproterenol challenge. Acute procedural and safety data were assessed. Systematic char evaluation was performed.

Results

Effectiveness analysis included 38/40 subjects with mean 110-day follow up (mean age, 61.7 ± 9.5 years; 63.2% male). Hypertension (47.4%) and congestive heart failure (15.8%) were the most common comorbidities. Fourteen subjects were treated with version V0 of the generator, and 24 subjects were treated using version V1c which included further software adjustments to the power titration, and current response to optimize performance. Combination vHPSD/CP workflow was used for PV isolation in 28 (75.7%) subjects and vHPSD was used solely in 10. A non-study catheter was used in 1 subject during connectivity troubleshooting. Primary endpoint of entrance block confirmation was achieved in 37/38 subjects and in all 37 subjects treated with study catheter only. No incidences of char or device-related adverse events were reported. There were no noted differences in the endpoints evaluated between the V0 and V1c groups. Median (Q1/Q3) RF application times for ablating PVs was 13.0 min (9.0/16.0) for the entire cohort. Median (Q1/Q3) time to achieve PV isolation in vHPSD-only group was 9 (7/12) min, and 14 (11/18) min, respectively.

Conclusion(s)

Consistent with data from prior 3 clinical studies, QDM catheter with the new 90W-enabled generator demonstrated the acute safety and effectiveness of temperature-controlled AF ablation with short PV ablation time and no char observed.

Grading of Anatomopathological Disparity in the Cases of Invasive Pulmonary Aspergillosis in wild avian species as recorded in Pigeons (Columba livia), Peafowls (Pavo cristatus), and Griffon Vultures (Gyps fulvus)

Aspergillosis which is caused by Aspergillus fumigatus, a fungal pathogen, can vary from a localized infection to severe life-threatening invasive or disseminated systemic diseases in birds. The present study aimed to evaluate and grade the anatomopathological disparity in the cases of invasive pulmonary aspergillosis (IPA) in Columba livia (pigeons), Pavo cristatus (peafowls), and Gyps fulvus (Griffon vultures). Necropsy gross lesions varied from mere congestion of lungs in P. cristatus, congestion and large necrotizing masses surrounded by a zone of hyperemia (10 mm dia) in lungs of C. livia, and typically disseminated granuloma in the lungs, air sacs, and organs of other serous membranes in G. fulvus. Histopathology varied from extensive parenchymal necrosis amidst exuberant fungal invasion in P. cristatus, multifocal to focally extensive tissue necrosis with colonies of fungal hyphae surrounded by heterophils and lymphocytes in C. livia, as well as typical mycotic granuloma embedded in the lungs, air sacs, and thoracoabdominal serous membranes with angio-invasion in G. fulvus. Based on gross and histopathological findings, we diagnosed the cases as Acute Invasive Pulmonary Aspergillosis (AIPA) in peafowls and pigeons, as well as Chronic Invasive Pulmonary Aspergillosis (CIPA) in Griffon vultures. There is a paucity of case reports on aspergillosis in wild avian species, and this report strived to document the cases of IPA in peafowls, pigeons, and vultures. This is the first report of its kind which evaluated anatomopathological disparity of IPA in pigeons, peafowls, and vultures with a proposed anatomopathological grading system which would help to understand and investigate the nature of aspergillosis in different avian hosts.

A systematic review and meta-analysis of disease burden of healthcare-associated infections in China: an economic burden perspective from general hospitals

BACKGROUND

Healthcare-associated infections (HAIs) are a global public health issue. However, the economic burden attributable to HAIs at a national level is unknown in China. The aim of this systematic review was to estimate the direct economic burden caused by HAIs in China.

METHODS

Medline, EMBASE and Chinese Journals Online databases were searched, including studies published from 2009 to 2019. The pooled estimates with 95% Confidential Interval were calculated with Quantile Estimation. The random effect model of the DerSimonian-Laird method was used. The statistical significance was set as P<0.05.

RESULTS

2,756 publications were identified; 6 studies were included in a meta-analysis to calculate the pooled estimates of direct economic burden, while 5 were included in the pooled estimates of the additional economic burden. The pooled median estimates of the total medical expenditure, the medicine expenditure and hospitalisation days per inpatient of patients with HAIs were ¥34,415.62, ¥20,065.21 and 34.01 days, respectively (P <0.0001). The pooled median estimates of the differences of the total medical expenditure, the medicine expenditure and hospitalisation days per inpatient between patients with HAIs and patients without HAIs were ¥24,881.37, ¥9,438.46 and 13.89 days, respectively (P < 0.01).

CONCLUSIONS

The cost of care for patients with HAIs was significantly higher than that for those without HAIs. This excess economic burden is likely to impact on patients and their families as well as health service providers and the health care system as a whole. Effective surveillance systems and cost-effective interventions are needed to control HAIs.

Metastatic Neoplasms of the Large Bile Ducts- A Clinicopathological Study

Introduction/Objective

Biliary strictures are often considered malignant until proven otherwise. While the majority of malignant biliary strictures represent a primary neoplasm, secondary involvement by metastasis also rarely occurs. Primary cholangiocarcinoma and metastatic disease have different treatment considerations and likely different prognoses. The aim of this study is to look at the clinico-pathological characteristics of metastatic neoplasms of the bile duct.

Methods/Case Report

We retrospectively searched the pathology archives for biliary biopsies between 1991-2020. Patients with primary biliary, gallbladder, pancreatic, ampullary and hepatic malignancies and all cases of lymphoma were excluded from the study. A total of 20 cases were included.

Results (if a Case Study enter NA)

The median age of the patients was 63 years with a M:F ratio of 1.9:1. The biopsies were taken from the common bile duct (n=17), common hepatic duct (n=2) and left hepatic duct (n=1). 8 patients had synchronous and 12 had metachronous presentation. The overall median interval between the bile duct metastasis and primary was 18 months (Range: 0-100 months) for all patients and 33 months for metachronous cases. For 13 tumors, the primary site of origin was in the gastrointestinal tract (colon: 7; stomach: 4; anal canal: 1; gastro-esophageal junction: 1). Other primary sites included breast (3 cases), lung, endometrium and adrenal (1 each). One case presented with metastatic melanoma with an occult primary. Adenocarcinoma was the most common histological subtype seen in 17 cases. Other histological subtypes were squamous cell carcinoma, adrenocortical carcinoma and melanoma.

Conclusion

Secondary involvement of the bile duct by metastasis is rare. Most cases are metastasis from the lumenal gastrointestinal tract, with colon being the most common primary site. They are more likely to have a metachronous presentation with rare instances of bile duct metastasis as the first presentation. Awareness of secondary involvement of the biliary tree by metastasis is important as they can have prognostic and therapeutic significance.

Atrial fibrillation in unexplained syncope: observations from the Reveal LINQ registry

Background

Implantable loop recorders (ILRs) have come to play an important role in the workup of patients with recurrent syncope of uncertain origin. In addition to detecting bradyarrhythmias related to syncope, which is the main diagnostic focus in these patients, ILRs are also capable of uncovering subclinical atrial fibrillation (AF).

Purpose

We sought to determine the percentage of patients monitored with an ILR for unexplained syncope who have AF detected and to describe clinical actions taken in these patients.

Methods

Patients enrolled in the Reveal LINQ Registry who received an ILR for unexplained syncope and had at least one follow-up form were included. The device automatically detects AF episodes lasting ≥2 minutes. Patients were considered to have AF based on an AF diagnosis made by the treating physician during follow-up or if device-detected AF was adjudicated as true AF by an external reviewer. AF detection rates were calculated using Kaplan-Meier methods.

Results

In total, 498 patients (aged 61.8±20.0 years, 49.6% female, CHA2DS2VASc score 2.2±1.7) were included and followed for 22±12 months. A history of AF was present in 97 (20%) patients, while 401 patients had no history. By 18 months, the incidence of AF was 70.9% (95% CI, 60.8%, 80.3%) in patients with a history of AF and 21.4% (95% CI, 17.4%, 26.1%) in patients without (Figure). AF detection in those with (30.4%) and without (30.1%) syncope during follow-up was similar. By the end of follow-up, and among patients with newly detected AF, 29/86 (33.7%) were on oral anticoagulation, 7 (8.1%) underwent AF ablation, 6 (7.0%) underwent other type of ablation, and 2 (2.3%) received cardioversion. Other actions among the whole cohort included implant of an IPG, ICD, or CRT in 98/498 (19.7%).

Conclusion

Among patients monitored with ILRs to determine the cause of recurrent syncope episodes, approximately 1 in 5 patients had new AF detected. In addition to improving the management of patients with syncope, ILR data served to support AF-related clinical decisions.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Medtronic Inc Incidence of AF according to baseline AF

Perinatal mental health in India: protocol for a validation and cohort study

BACKGROUND

Common mental disorders (CMD) are among the largest contributors to global maternal morbidity and mortality. Although research on perinatal mental health in India has grown in recent years, important evidence gaps remain, especially regarding CMD. Our study aims to improve understanding of CMD among perinatal and non-perinatal women of reproductive age across two settings in India: Bangalore (Karnataka) and Tanda (Himachal Pradesh).

METHODS

The study is embedded within the Maternal and Perinatal Health Research Collaboration India (MaatHRI). This mixed-methods observational study comprises three consecutive phases: (i) focus group discussions and individual interviews to explore women's knowledge and seek feedback on CMD screening tools; (ii) validation of CMD screening tools; and (iii) prospective cohort study to identify CMD incidence, prevalence and risk factors among perinatal and non-perinatal women. Results of the three phases will be analyzed using inductive thematic analysis, psychometric analysis and multivariable regression analysis, respectively.

CONCLUSION

Improving understanding, detection and management of CMD among women is key to improving women's health and promoting gender equality. This study will provide evidence of CMD screening tools for perinatal and non-perinatal women in two diverse Indian settings, produce data on CMD prevalence, incidence and risk factors and enhance understanding of the specific contribution of the perinatal state to CMD.

DART: deep learning enabled topological interaction model for energy prediction of metal clusters and its application in identifying unique low energy isomers

Recently, machine learning (ML) has proven to yield fast and accurate predictions of chemical properties to accelerate the discovery of novel molecules and materials. The majority of the work is on organic molecules, and much more work needs to be done for inorganic molecules, especially clusters. In the present work, we introduce a simple topological atomic descriptor called TAD, which encodes chemical environment information of each atom in the cluster. TAD is a simple and interpretable descriptor where each value represents the atom count in three shells. We also introduce the DART deep learning enabled topological interaction model, which uses TAD as a feature vector to predict energies of metal clusters, in our case gallium clusters with sizes ranging from 31 to 70 atoms. The DART model is designed based on the principle that the energy is a function of atomic interactions and allows us to model these complex atomic interactions to predict the energy. We further introduce a new dataset called GNC_31-70, which comprises structures and DFT optimized energies of gallium clusters with sizes ranging from 31 to 70 atoms. We show how DART can be used to accelerate the process of identification of low energy structures without geometry optimization. Albeit using a topological descriptor, DART achieves a mean absolute error (MAE) of 3.59 kcal mol^-1 (0.15 eV) on the test set. We also show that our model can distinguish core and surface atoms in the Ga-70 cluster, which the model has never encountered earlier. Finally, we demonstrate the transferability of the DART model by predicting energies for about 6k unseen configurations picked up from molecular dynamics (MD) data for three cluster sizes (46, 57, and 60) within seconds. The DART model was able to reduce the load on DFT optimizations while identifying unique low energy structures from MD data.

Smirnov A, Verma A, Woods K. Compact X-Band Electron Linac for Radiotherapy and Security Applications

RadiaBeam has developed a 6 MeV accelerator that is compact and light enough to be placed on a robotic arm or light truck. The main drivers of size and weight in conventional accelerators are the power source and the shielding. Small dimensions are enabled by operation at 9.3 GHz frequency (X-band), which allows reducing the size and weight of all accelerator components. Thanks to the robust design of the accelerating structure, the accelerator can be used as a source for novel cargo inspection and radiotherapy techniques. In this paper, we present the linac design and its components, as well the results of the experimental demonstration of beam acceleration.

Stress and Molecular Drivers for Cancer Progression: A Longstanding Hypothesis

Stress management is becoming very important part of cancer patient care. Chronic stressors lead to boost tumorigenesis and promote cancer development, recurrence, and drug resistant leading to poor health outcomes. The Hypothalamic-Pituitary-Adrenal (HPA) axis, which is activated by stress, also regulates Hypothalamic-Pituitary-Thyroid (HPT) axis. Stress related changes in immune function and inflammatory response also leads to reduced immune surveillance resulting in tumorigenesis. This article explores the hormonal axis impacted by stress and how chronic stress can lead to poor outcome of a cancer patient.

Genome-wide analysis in 756,646 individuals provides first genetic evidence that ACE2 expression influences COVID-19 risk and yields genetic risk scores predictive of severe disease

SARS-CoV-2 enters host cells by binding angiotensin-converting enzyme 2 (ACE2). Through a genome-wide association study, we show that a rare variant (MAF = 0.3%, odds ratio 0.60, P=4.5×10^-13) that down-regulates ACE2 expression reduces risk of COVID-19 disease, providing human genetics support for the hypothesis that ACE2 levels influence COVID-19 risk. Further, we show that common genetic variants define a risk score that predicts severe disease among COVID-19 cases.

Surgical management of the odontogenic keratocyst: A 20-year experience

The objective of this study was to describe the authors' long-term experience with the management of odontogenic keratocysts (OKCs). All OKC cases treated at the study centre between 1999 and 2015, with a minimum of 5 years of follow-up by December 2019, were reviewed retrospectively. Operative procedures including decompression/marsupialization, enucleation (E), E+Carnoy's solution (CS), E+CS+peripheral ostectomy (PO), and resection were assessed for complete resolution, partial resolution, and recurrence rates. In the parakeratinized non-syndromic group, E+CS+PO resulted in the lowest recurrence rate among the minimally invasive procedures (4.3%), while enucleation resulted in the highest rate (60%). Regarding the other modalities, recurrence was 12.5% for decompression, 11.5% for marsupialization, 16.7% for E+CS, 26.7% for E+PO, and 0% for resection. In the syndromic group, marsupialization resulted in a significantly higher recurrence (23.1%), while E+CS+PO cases showed no recurrence. No recurrence was observed in the orthokeratinized group patients treated with marsupialization or with E+CS. Based on clinico-radiographic features and observed results, it is concluded that OKC, although having a high recurrence rate, is a benign lesion and responds well to conservative procedures in most cases. Radical procedures should be reserved for unresponsive lesions and those with extensive tissue destruction.

A catalog of associations between rare coding variants and COVID-19 outcomes

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes coronavirus disease-19 (COVID-19), a respiratory illness that can result in hospitalization or death. We investigated associations between rare genetic variants and seven COVID-19 outcomes in 543,213 individuals, including 8,248 with COVID-19. After accounting for multiple testing, we did not identify any clear associations with rare variants either exome-wide or when specifically focusing on (i) 14 interferon pathway genes in which rare deleterious variants have been reported in severe COVID-19 patients; (ii) 167 genes located in COVID-19 GWAS risk loci; or (iii) 32 additional genes of immunologic relevance and/or therapeutic potential. Our analyses indicate there are no significant associations with rare protein-coding variants with detectable effect sizes at our current sample sizes. Analyses will be updated as additional data become available, with results publicly browsable at https://rgc-covid19.regeneron.com.

Care of People with Epilepsy in Rural Medical Centre of Developing Countries with Limited Resources: During the COVID-19 Pandemic

Coronavirus disease 2019 (COVID-19) has become a pandemic disease globally. This extraordinary situation is posing an enormous burden on the healthcare systems worldwide and is reshaping the way in which chronic disorders are managed. Pandemic has made epilepsy care even more demanding in rural part of developing countries. We outline the adverse circumstances in epilepsy care induced by the pandemic; propose emergency management and follow up care of people with epilepsy. There is a requirement for public health systems in resource poor countries to improve awareness, implement proper strategies of triage, acute treatment, telemedicine services and virtual check-ins.

Possible treatment and strategies for COVID-19: review and assessment

The coronavirus disease 2019 (COVID-19) is declared as an international emergency in 2020. Its prevalence and fatality rate are rapidly increasing but the medication options are still limited for this perilous disease. The emergent outbreak of COVID-19 triggered by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) keeps propagating globally. The present scenario has emphasized the requirement for therapeutic opportunities to relive and overcome this latest pandemic. Despite the fact, the deteriorating developments of COVID-19, there is no drug certified to have considerable effects in the medical treatment for COVID-19 patients. The COVID-19 pandemic requests for the rapid testing of new treatment approaches. Based on the evidence, hydroxychloroquine is the first medicine opted for the treatment of disease. Umifenovir, remdesivir, and fevipiravir are deemed the most hopeful antiviral agent by improving the health of infected patients. The dexamethasone is a first known steroid medicine that can save the lives of seriously ill patients, and it is shown in a randomized clinical trial by the United Kingdom that it reduced the death rate in COVID-19 patients. The current review recapitulates the existing evidence of possible therapeutic drugs, peptides, humanized antibodies, convulsant plasma, and vaccination that has revealed potential in fighting COVID-19 infections. Many randomized and controlled clinical trials are taking place to further validate these agent's safety and effectiveness in curing COVID-19.