The Utility of Leadless Atrioventricular Synchronous Pacemaker Implantation as a Novel Alternative to a Traditional Pacemaker During Pregnancy.

The Micra™ leadless pacemaker (Medtronic, Minneapolis, MN, USA) is indicated for the management of symptomatic bradycardia and advanced heart block. However, the safety of this procedure during pregnancy has not been studied. Here, we present a unique case of Micra™ leadless pacemaker implantation (MLP) in a 31 weeks pregnant patient with intermittent complete heart block who presented with multiple syncopal episodes. The patient underwent an MLP implantation with <40 mGy radiation exposure (about 0.6 min of total fluoroscopy time), which is deemed a negligible dose of radiation exposure during pregnancy. Her subsequent hospital course was uneventful, and she was safely discharged home and was able to continue her pregnancy and delivery without further syncopal episodes or incidence of heart block.

Implication of the micro- and lithofacies types on the quality of a gas-bearing deltaic reservoir in the Nile Delta, Egypt.

The Messinian Qawasim sequence, as one of the most important reservoirs in the Egyptian Nile Delta, represents a typical gas-bearing deltaic reservoir sequence. It aims at delineating the implication of the litho- and microfacies associations on the reservoir characteristics of the different stages of the fluvial deltas including the prodelta, proximal/distal delta front, and the delta plain depositional sequences. The studied reservoir sequence was divided into two units; upper and lower clastic units. The petrophysical properties of these two units were studied on the borehole scale using the gamma-ray, caliper, sonic, density, neutron, and resistivity logs to estimate the reservoir parameters including the total and effective porosities, water saturation, shale volume, and the net-pay thickness. For more details, they are also examined on the plug-scale using the core dataset including helium porosity, density, permeability, and fluids saturations, where the flow zone indicator, the reservoir potentiality index, the reservoir quality index, and the average reservoir pore radius were then estimated. The entire sequence is divided into five reservoir rock types (RRT1-RRT5) where, the best quality is assigned to the first RRT (the upper reservoir unit), and the lowest quality is assigned to the RRT5 of the lower reservoir unit. Based on core description and the petrographical studies five lithofacies and four microfacies have been identified. The lithofacies are (1) laminated mudstones/siltstones, (2) ripple laminated sandstones, (3) cross-laminated sandstones, (4) cross-bedded sandstones, and (5) pebbly massive sandstones. These lithofacies are primarily composed of four microfacies; sublithic arenites, subarkose arenite, glauconitic quartz wacke, and sandy mudstone/siltstone. Based on this study, the pebbly massive and the cross-bedded sandstones of the upper unit which is composed of the sublithic and subarkose arenites (RRT1-RRT2) have the best reservoir quality. On the other hand, the lowest quality is assigned to the RRT5 (sandy mudstone/siltstone microfacies) which is represented on the macro scale by the laminated mudstones/siltstones lithofacies. The integration between multi-scale datasets (core-well, petrography, well logs, and seismic) gives a precise picture of the deltaic Qawasim reservoir rock units in the Nile Delta. This workflow has never been applied to the deltaic system in the onshore Nile delta and North Africa. Thereby, this study is considered a standard case study for the deltaic sequences and its proposed workflow is applicable to the Nile Delta elsewhere and worldwide for similar reservoir sequences.

Characteristics of warfarin under-prescription in older adults with atrial fibrillation.

BACKGROUND: The prevalence of atrial fibrillation (AF) and atrial flutter (AFl) increases with age. Under-prescription of anticoagulants in older adults can lead to increased morbidity and mortality. We analyzed warfarin prescription patterns in older adults. METHODS: In this observational single-center study, we analyzed 2179 consecutive patients with admission diagnosis of AF or AFl. Patients were divided into "older" (≥ 75 years old) and "younger" (<75 years old) groups. Prescription patterns of warfarin were analyzed. Patients discharged from the hospital on a non-warfarin anticoagulation were excluded. RESULTS: Of the 1988 patients analyzed, 46.9% were ≥75 years old, of which 50.8% were prescribed warfarin. There was no association between mean CHA2DS2-VASc score and warfarin prescription on discharge (OR = 1.06 (95% CI 0.93-1.21), p = 0.388) in the older group. After adjusting for hypertension, renal function, and Black race, warfarin prescription in older adults was independently associated with lower aspirin prescription rates (OR = 0.57 (95% CI 0.43-0.75), p < 0.001), lower body mass index (OR = 1.03 (95% CI 1.01-1.06), p = 0.018), and lower hemoglobin levels (OR = 1.11 (95% CI 1.04-1.19), p = 0.002). CONCLUSIONS: In our study, older adults (≥75 years old) with AF and AFl tended to have lower rates of warfarin prescription despite higher CHA2DS2-VASc score and higher risk of thromboembolic events. Anemia, lower body weight, and aspirin use were characteristics associated with warfarin under-prescription.

Micra™ Leadless Intracardiac Pacemaker Implantation: A Safer Option During the Coronavirus Disease 2019 Pandemic.

The Micra™ Transcatheter Pacing System (Medtronic, Minneapolis, MN, USA) is a fairly novel leadless intracardiac pacemaker implanted in the right ventricle via a femoral-vein transcatheter approach. Due to the less-invasive nature of the implantation procedure and its smaller size, patients receiving the Micra™ device tend to experience fewer complications, hospitalizations, and revisions when compared with those with transvenous pacemakers. Certain arrhythmias and conduction abnormalities, such as high-degree atrioventricular blocks, require urgent and timely pacemaker insertion-a necessity that has persisted even during the coronavirus disease 2019 (COVID-19) pandemic. Here, we present a case series of 10 patients with various conduction disease abnormalities who required right ventricle pacemaker implantation during the months of March to May 2020, which was the initial peak of the COVID-19 pandemic in New Jersey, including the enhanced precautions taken to avoid viral spread.

Key lessons from Hurricane Dorian: The benefits of a flexible top-down storm response.

In 2019, Hurricane Dorian wreaked widespread havoc across the Province of Nova Scotia, with significant, adverse impacts affecting citizens and government services for a protracted period. This paper describes the challenges faced by the provincial emergency management and business continuity response teams. It argues that storm response requires a flexible top-down approach, with senior leadership delegating responsibility and encouraging locally-driven decision-making. Using examples from Hurricane Dorian, the paper shows that as emergency response and business continuity overlap, response teams must find a balance between the protection of life and property and safeguarding the continuity of business. This can be accomplished through strategic support from senior leadership, the adoption of evolving best practices and competency development through training and realistic exercise scenarios.

Metaanalysis of Multivessel vs Culprit Artery Only Percutaneous Coronary Intervention in ST Elevation Myocardial Infarction.

Background: Primary percutaneous coronary intervention (PCI) is the most frequently used treatment modality for patients presenting with ST elevation myocardial infarction (STEMI). Current professional society guidelines recommend culprit artery only PCI. Recent evidence suggests the potential benefit of multivessel PCI among patients with STEMI that is not complicated by cardiogenic shock. Methods: We systematically searched PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials for clinical studies of patients with STEMI, not complicated by cardiogenic shock, who underwent primary PCI between January 1966 and January 2018. We evaluated all-cause and cardiovascular mortality, reinfarction, and repeat revascularization among patients randomized to a multivessel PCI strategy compared to a culprit artery only PCI strategy. Results: Four randomized clinical trials with a total of 1,044 patients met the inclusion criteria. Five hundred and sixty-six patients underwent multivessel PCI, and 478 patients underwent culprit artery only PCI. Multivessel PCI reduced all the studied endpoints: total death, cardiac death, reinfarction, and repeat revascularization (all P values <0.05). Conclusion: To our knowledge, this is the largest metaanalysis of randomized controlled trials studying multivessel PCI vs culprit artery only PCI in STEMI patients without shock, among whom lesion severity was graded by angiography alone. We found that compared to culprit artery only PCI, the multivessel PCI strategy was beneficial in reducing all-cause and cardiovascular mortality, reinfarction, and the need for repeat revascularization.

Retraction: On the enzymatic activity of catalase: an iron L-edge X-ray absorption study of the active centre.

Retraction of 'On the enzymatic activity of catalase: an iron L-edge X-ray absorption study of the active centre' by Nora Bergmann et al., Phys. Chem. Chem. Phys., 2010, 12, 4827-4832.

Use of MPH hemostatic powder for electrophysiology device implantation reduces postoperative rates of pocket hematoma and infection.

BACKGROUND: Surgical site bleeding and infection are potential complications after electrophysiology (EP) device implantation procedures. To date, there is a wide variety of tools for management of intraoperative bleeding but it still remains unclear what methods are preferred. OBJECTIVE: The aim of our study is to compare the rate of complications in patients who underwent cardiac implantable electronic device (CIED) implantation utilizing MPH hemostatic powder to the rate of complications in those patients who underwent standard procedure protocol without MPH hemostatic powder. METHODS: In our study, a new plant-derived microporous polysaccharide hemostatic powder (Arista) was used. A total of 283 consecutive patients were retrospectively studied to assess the rate of complications in patients who underwent CIED implantation with MPH hemostatic powder (n = 77, MPH hemostatic powder) and without (n = 206, no MPH hemostatic powder). Patients were followed for 12 months. RESULTS: The MPH hemostatic powder group of patients had a lower complication rate when compared to no MPH hemostatic powder, 0.3% vs. 1.7% (p < .05), respectively. The rate of device implantation site MPH hematoma in the MPH hemostatic powder group was 0.4%, versus 0.9% in the other group. There were no postoperative infections in the MPH hemostatic powder group versus 3.2% infections in the other group. The main predictor of increased risk of post-procedural complication was the usage of anticoagulation with a hazard ration of 2.7. CONCLUSION: Using MPH hemostatic powder for post-procedural hemostasis was shown to result in a significant reduction in the rate of overall post-procedural complications (a composite endpoint of hematoma and infections), and a trend in reduction of the infections rates and device implantation site hematoma rates.

Pathway for the Management of Hyperglycemia in the Cardiac Care Unit.

Inpatient hyperglycemia has been associated with increased morbidity and mortality in critically ill patients. Optimal control of blood glucose (BG) levels using insulin infusion protocols has been shown to improve clinical outcomes. Protocols have been developed to prescribe a safe and effective rate of insulin infusion for optimal control of BG levels; however, a major obstacle in their implementation is their complexity. We have revised and updated our previously published pathway for the management of hyperglycemia, which introduces the "wheel" concept for insulin dosing. The "wheel" serves as a treatment guide. It is made up of 6 concentric circles. The core circle represents the goal of BG in critically ill patients, with inner circle showing the actual BG range of the patient. The 4 outer circles correspond to increasing rates of insulin infusion from tier 1 to tier 4. Simple guidelines are provided to facilitate conversion from insulin infusion to a subcutaneous insulin-delivery regimen in preparation for transfer from the cardiac care unit (CCU) setting. Our protocols also provide guidelines for management of diabetic ketoacidosis and hyperosmolar hyperglycemic states while at the same time creates a flowchart for activation of diabetes care team and their involvement in the multidisciplinary care of a patient in CCU with hyperglycemia and/or diabetes mellitus. This pathway provides a comprehensive and detailed, yet simple and practical algorithm for management of hyperglycemia in the CCU.

Bulk-Sensitive Detection of the Total Ion Yield for X-ray Absorption Spectroscopy in Liquid Cells.

Detection of ionic current with two electrodes installed in a liquid cell has been established previously as an effective method, termed as total ion yield (TIY), to acquire X-ray absorption (XA) spectra of liquid solutions behind a membrane. In this study, the exact locations where TIY signals are generated are further investigated and unequivocally identified. The detected ionic current stems dominantly from the bulk solution species while only marginally from the species located at the membrane-solution interface. Such a two-electrode TIY detection in a liquid cell combines the advantages of bulk sensitivity of fluorescence yield and high signal strength (for light elements) of electron yield, exhibiting its novel and promising role in the XA spectroscopy measurements of liquid cells.

Erratum: Probing the Electronic Structure of the Hemoglobin Active Center in Physiological Solutions [Phys. Rev. Lett. 102, 068103 (2009)].

This corrects the article DOI: 10.1103/PhysRevLett.102.068103.

Heterogeneity of the Transmembrane Protein Conformation in Purple Membranes Identified by Infrared Nanospectroscopy.

Cell membranes are intrinsically heterogeneous, as the local protein and lipid distribution is critical to physiological processes. Even in template systems embedding a single protein type, like purple membranes, there can be a different local response to external stimuli or environmental factors, resulting in heterogeneous conformational changes. Despite the dramatic advances of microspectroscopy techniques, the identification of the conformation heterogeneity is still a challenging task. Tip-enhanced infrared nanospectroscopy is here used to identify conformational changes connected to the hydration state of the transmembrane proteins contained in a 50 nm diameter cell membrane area, without the need for fluorescent labels. In dried purple membrane monolayers, areas with fully hydrated proteins are found among large numbers of molecules with randomly distributed hydration states. Infrared nanospectroscopy results are compared to the spectra obtained with diffraction-limited infrared techniques based on the use of synchrotron radiation, in which the diffraction limit still prevents the observation of nanoscale heterogeneity.

Advances in liquid phase soft-x-ray photoemission spectroscopy: A new experimental setup at BESSY II.

A state-of-the-art experimental setup for soft X-ray photo- and Auger-electron spectroscopy from liquid phase has been built for operation at the synchrotron-light facility BESSY II, Berlin. The experimental station is named SOL3, which is derived from solid, solution, and solar, and refers to the aim of studying solid-liquid interfaces, optionally irradiated by photons in the solar spectrum. SOL3 is equipped with a high-transmission hemispherical electron analyzer for detecting electrons emitted from small molecular aggregates, nanoparticles, or biochemical molecules and their components in (aqueous) solutions, either in vacuum or in an ambient pressure environment. In addition to conventional energy-resolved electron detection, SOL3 enables detection of electron angular distributions by the combination of a ±11° acceptance angle of the electron analyzer and a rotation of the analyzer in the polarization plane of the incoming synchrotron-light beam. The present manuscript describes the technical features of SOL3, and we also report the very first measurements of soft-X-ray photoemission spectra from a liquid microjet of neat liquid water and of TiO2-nanoparticle aqueous solution obtained with this new setup, highlighting the necessity for state-of-the-art electron detection.

Pathway for the Management of Sleep Apnea in the Cardiac Patient.

Sleep-disordered breathing is a highly prevalent medical condition, which if undiagnosed leads to increased morbidity and mortality, particularly related to increased incidence of cardiovascular events. It is therefore imperative that we identify patient population at high risk for sleep apnea and refer them to the appropriate therapy as early as possible. Up-to-date there is no management guideline specifically geared towards cardiac patients. Thus, we propose a (SAP) Sleep Apnea Pathway to correctly identify and triage these patients to the appropriate therapy.

Sensitivity of Electron Transfer Mediated Decay to Ion Pairing.

Ion pairing in electrolyte solutions remains a topic of discussion despite a long history of research. Very recently, nearest-neighbor mediated electronic de-excitation processes of core hole vacancies (electron transfer mediated decay, ETMD) were proposed to carry a spectral fingerprint of local solvation structure and in particular of contact ion pairs. Here, for the first time, we apply electron-electron coincidence detection to a liquid microjet, and record ETMD spectra of Li 1s vacancies in aqueous solutions of lithium chloride (LiCl) in direct comparison to lithium acetate (LiOAc). A change in the ETMD spectrum dependent on the electrolyte anion identity is observed for 4.5 M salt concentration. We discuss these findings within the framework of the formation and presence of contact ion pairs and the unique sensitivity of ETMD spectroscopy to ion pairing.

Ultrafast kinetics of linkage isomerism in Na2[Fe(CN)5NO] aqueous solution revealed by time-resolved photoelectron spectroscopy.

The kinetics of ultrafast photoinduced structural changes in linkage isomers is investigated using Na2[Fe(CN)5NO] as a model complex. The buildup of the metastable side-on configuration of the NO ligand, as well as the electronic energy levels of ground, excited, and metastable states, has been revealed by means of time-resolved extreme UV (XUV) photoelectron spectroscopy in aqueous solution, aided by theoretical calculations. Evidence of a short-lived intermediate state in the isomerization process and its nature are discussed, finding that the complete isomerization process occurs in less than 240 fs after photoexcitation.

Retraction: Charge transfer to solvent identified using dark channel fluorescence-yield L-edge spectroscopy.

This corrects the article DOI: 10.1038/nchem.807.