Cardiac reentry, the underlying mechanism of both tachycardia and fibrillation, is often terminated clinically with extracellular stimuli. We developed a one-dimensional mathematical model to find the probability that a short, randomly-timed extracellular stimulus would terminate reentry and to study the mechanisms responsible for termination. Our ring model consisted of 100 atrial cells, with ...

Ibutilide can prolong refractory period and terminate reentry. Whether ibutilide has the same effects on pulmonary vein (PV) focal discharge (FD) is unclear. We induced sustained atrial fibrillation (AF) in seven dogs by rapid left atrial (LA) pacing for 74 +/- 46 days. Ibutilide was repeatedly infused until it terminated AF (0.02 +/- 0.01 mg/kg) or when a cumulative dose was reached (0.04 mg/k...

Neuronal modulation of the sinoatrial node (SAN) plays a crucial role in the initiation and maintenance of atrial arrhythmias (AF), although the exact mechanisms remain unclear. We used a computer model of a rabbit right atrium (RA) with a heterogeneous SAN and detailed ionic current descriptions for atrial and SAN myocytes to explore reentry initiation associated with autonomic activity. Heter...

INTRODUCTION Physicians returning to clinical practice after inactivity may face many challenges. Few programs provide reeducation, and data are limited about these experiences. We describe the physician refresher/reentry program at Drexel University College of Medicine, Philadelphia, and the lessons learned in our efforts to facilitate obstetrician-gynecologists' clinical reentry. METHODS In...

JANE CHRISTIE DAQUIN Vicarious Victimization: Examining the Effects of Witnessing Victimization While Incarcerated on Offender Reentry (Under the direction of DR. LEAH DAIGLE) Witnessing victimization in prison is a relatively new area of research. Prison victimization research focuses on direct experiences of victimization and its attending consequences; however, studies have not focused on th...

In normal heart, ventricular fibrillation can be induced by a single properly timed strong electrical or mechanical stimulus. A mechanism first proposed by Winfree and coined the "pinwheel experiment" emphasizes the timing and strength of the stimulus in inducing figure-of-eight reentry. However, the effects of cellular electrophysiological properties on vulnerability to reentry in the pinwheel...

BACKGROUND AND OBJECTIVE Although nonphysician reentry transitions have been characterized in literature, little is known about the reentry physicians in general, or residents in particular. We conducted a qualitative study to explore pediatric residents' reentry, using reverse culture shock as a conceptual framework. METHODS Eighteen pediatric residents who completed global health experience...

In this study we sought to determine whether characteristics of ventricular-induced atrial preexcitation during reciprocating tachycardia could help differentiate atrioventricular (AV) nodal reentry from orthodromic AV reentry using an accessory pathway and to identify the site of accessory pathways in patients with Wolff-Parkinson-White syndrome. Fifty-five patients with orthodromic AV recipro...