Cardiology Commons^™

The Hsp90 Inhibitor, Auy-922, Protects And Repairs Human Lung Microvascular Endothelial Cells From Hydrochloric Acid-Induced Endothelial Barrier Dysfunction, Ruben M.L. Colunga Biancatelli, Pavel Solopov, Betsy Gregory, John D. Catravas

Bioelectrics Publications

Exposure to hydrochloric acid (HCl) leads acutely to asthma-like symptoms, acute respiratory distress syndrome (ARDS), including compromised alveolo-capillary barrier, and respiratory failure. To better understand the direct effects of HCl on pulmonary endothelial function, we studied the characteristics of HCl-induced endothelial barrier dysfunction in primary cultures of human lung microvascular endothelial cells (HLMVEC), defined the involved molecular pathways, and tested the potentially beneficial effects of Heat Shock Protein 90 (HSP90) inhibitors. HCl impaired barrier function in a time- and concentration-dependent manner and was associated with activation of Protein Kinase B (AKT), Ras homolog family member A (RhoA) and myosin light …

Electroporation Safety Factor Of 300 Nanosecond And 10 Millisecond Defibrillation In Langendorff-Perfused Rabbit Hearts, Johanna U. Neuber, Andrei G. Pakhomov, Christian W. Zemlin

Bioelectrics Publications

Aims

Recently, a new defibrillation modality using nanosecond pulses was shown to be effective at much lower energies than conventional 10 millisecond monophasic shocks in ex vivo experiments. Here we compare the safety factors of 300 nanosecond and 10 millisecond shocks to assess the safety of nanosecond defibrillation.

Methods and results

The safety factor, i.e. the ratio of median effective doses (ED50) for electroporative damage and defibrillation, was assessed for nanosecond and conventional (millisecond) defibrillation shocks in Langendorff-perfused New Zealand white rabbit hearts. In order to allow for multiple shock applications in a single heart, a pair of needle electrodes …

In Silico Investigation Of Cardiac Arrhythmia Susceptibility In Long Qt Phenotype, Anthony Owusu-Mensah, Victoria Lam, Bright Tsevi, Michel Audette, Makarand Deo

Electrical & Computer Engineering Faculty Publications

Long QT Syndrome (LQTS) is associated with cardiac arrhythmia and sudden cardiac death. The Long QT Type 2 (LQT2) phenotype, which accounts for 35–40 % of all LQTS patients, is caused by mutations in HERG gene. The mechanisms of arrhythmia in presence of LQT2 conditions are not fully understood. We utilized anatomically and electrophysiologically realistic numerical simulations to elucidate the mechanisms of arrhythmia initiation in presence of blockade in rapid component of delayed rectifier potassium current, I_Kr. We utilized a 3D finite element model of rabbit ventricles integrated with His-purkinje network to simulate whole heart response to LQT2 …

Initiation Of Action Potential In Murine Ventricular Myocytes By Bursts Of Nanosecond Pulses, Iurii Semenov

Bioelectrics Publications

[First slide] Current situation

I. Among 300,000 persons die from sudden cardiac arrest every year over 40% are victims of fibrillation

II. Defibrillation by an electric shock is the effective therapy against sudden cardiac death

III. Current approach to stop fibrillation may involve disruption of plasma membrane (PM) by an electroporation

IV. Electroporation is damaging, it can: I. Induce post shock arrhythmias II. Complicate patient's recovery III. Lead to death after initially successful resuscitation

Effect Of Twisted Fiber Anisotropy In Cardiac Tissue On Ablation With Pulsed Electric Fields, Fei Xie, Christian W. Zemlin

Bioelectrics Publications

Background: Ablation of cardiac tissue with pulsed electric fields is a promising alternative to current thermal ablation methods, and it critically depends on the electric field distribution in the heart.

Methods: We developed a model that incorporates the twisted anisotropy of cardiac tissue and computed the electric field distribution in the tissue. We also performed experiments in rabbit ventricles to validate our model. We find that the model agrees well with the experimentally determined ablation volume if we assume that all tissue that is exposed to a field greater than 3 kV/cm is ablated. In our numerical analysis, we considered …

Categorizing Fetal Heart Rate Variability With And Without Visual Aids, Amanda J. Ashdown, Mark W. Scerbo, Lee A. Belfore Ii, Stephen S. Davis, Alfred Z. Abuhamad

Psychology Faculty Publications

Objective This study examined the ability of clinicians to correctly categorize images of fetal heart rate (FHR) variability with and without the use of exemplars.

Study Design A sample of 33 labor and delivery clinicians inspected static FHR images and categorized them into one of four categories defined by the National Institute of Child Health and Human Development (NICHD) based on the amount of variability within absent, minimal, moderate, or marked ranges. Participants took part in three conditions: two in which they used exemplars representing FHR variability near the center or near the boundaries of each range, and a third …

The Search For High-Impact Diagnostic And Management Tools For Low-And Middle-Income Countries: A Self-Powered Low-Cost Blood Pressure Measurement Device Powered By A Solid-State Vibration Energy Harvester, Onur Bilgen, John G. Kenerson, Muge Akpinar-Elci, Rebecca Hattery, Lisbet M. Hanson

Mechanical & Aerospace Engineering Faculty Publications

The World Health Organization has established recommendations for blood pressure measurement devices for use in low-resource venues, setting the triple A expectations of Accuracy, Affordability, and Availability. Because of issues related to training and assessment of proficiency, the pendulum has swung away from manual blood pressure devices and auscultatory techniques towards automatic oscillometric devices. As a result of power challenges in the developing world, there has also been a push towards semiautomatic devices that are not dependent on external power sources or batteries. Beyond solar solutions, disruptive technology related to solid-state vibrational energy harvesting may be the next iterative solution …

Ablation Of Myocardial Tissue With Nanosecond Pulsed Electric Fields, Fei Xie, Frency Varghese, Andrei G. Pakhomov, Iurii Semenov, Shu Xiao, Jonathan Philpott, Christian Zemlin

Bioelectrics Publications

Background

Ablation of cardiac tissue is an essential tool for the treatment of arrhythmias, particularly of atrial fibrillation, atrial flutter, and ventricular tachycardia. Current ablation technologies suffer from substantial recurrence rates, thermal side effects, and long procedure times. We demonstrate that ablation with nanosecond pulsed electric fields (nsPEFs) can potentially overcome these limitations.

Methods

We used optical mapping to monitor electrical activity in Langendorff-perfused New Zealand rabbit hearts (n = 12). We repeatedly inserted two shock electrodes, spaced 2–4 mm apart, into the ventricles (through the entire wall) and applied nanosecond pulsed electric fields (nsPEF) (5–20 kV/cm, 350 ns duration, …

Orientation-Invariant Ecg-Based Virtual Pathology Stethoscope Tracking For Standardized Patient Heart Auscultation, Nahom B. Kidane

Computational Modeling & Simulation Engineering Theses & Dissertations

Cardiac auscultation (CA), the act of listening to the heart sounds, is a critical physician's skill that provides substantial information for diagnosing many cardiovascular disorders; therefore, competent training can be a key for accurate and reliable diagnosis. The teaching of CA has been an area of recognized importance since the inception of the stethoscope. However, recent changes in health-care, such as limited student access to patients and higher reliance on competing technologies have made it challenging to teach bedside CA techniques.

Over the past few decades, standardized patients (SPs), individuals trained to portray real patients, have been widely used for …

Sir/Rsna/Cirse Joint Medical Simulation Task Force Strategic Plan: Executive Summary, Derek Gould, Aalpen Patel, Gary Becker, Buddy Conners, John Cardella, Steven Dawson, Craig Glaiberman, David Kessel, Mick Lee, Mark Scerbo

Psychology Faculty Publications

(First paragraph) The Executive Councils of the Society of Interventional Radiology (SIR), Radiological Society of North America (RSNA), and Cardiovascular and Interventional Radiological Society of Europe (CIRSE) have charged their Medical Simulation Task Forces and Work Groups to cooperate to achieve excellence and safety in interventional radiology patient care by jointly recommending and guiding implementation of a robust infrastructure and process to support Interventional Radiology (IR) simulation development, assessment, validation, application, and dissemination.