A Case of Acute Ventricular Capture Threshold Rise Associated with Flecainide Acetate

Antiarrhythmic agents may increase capture threshold, but this is rarely of clinical significance. Flecainide acetate, a class IC agent, is reported to have a significant effect on the myocardial capture threshold. In this presentation, we report the case of a 72-year-old male, with a previously implanted VVI pacemaker due to sick sinus syndrome, who was treated with flecainide acetate for paroxysmal atrial arrhythmia control. During the fifteenth day of treatment, an abrupt rise in the ventricular capture threshold with ventricular pacing failure was noted. The capture threshold decreased two days after discontinuation of flecainide acetate

Twenty-five years in the making: flecainide is safe and effective for the management of atrial fibrillation

Atrial fibrillation (AF) is the most common arrhythmia in clinical practise and its prevalence is increasing. Over the last 25 years, flecainide has been used extensively worldwide, and its capacity to reduce AF symptoms and provide long-term restoration of sinus rhythm (SR) has been well documented. The increased mortality seen in patients treated with flecainide in the Cardiac Arrhythmia Suppression Trial (CAST) study, published in 1991, still deters many clinicians from using flecainide, denying many new AF patients a valuable treatment option. There is now a body of evidence that clearly demonstrates that flecainide has a favourable safety profile in AF patients without significant left ventricular disease or coronary heart disease. As a result of this evidence, flecainide is now recommended as one of the first-line treatment options for restoring and maintaining SR in patients with AF under current treatment guidelines. The objective of this article is to review the literature pertaining to the pharmacological characteristics, safety and efficacy of flecainide, and to place this drug in the context of current therapeutic management strategies for AF

Video Rate Shading For Volume Data

This paper presents a new system for the generation of video rate images from voxel based volume data, in which novel approaches have been applied to the problems of shading and lighting. The shading algorithm combines a three dimensional 3 \Theta 3 \Theta 3 window of voxels with look up table based shading. A restricted lighting and viewing model reduces calculation complexity without greatly affecting medical information present in images. Many applications of this technology currently exist and further applications are possible through the exploration of other volume visualisation techniques. 1 INTRODUCTION Three dimensional imaging of volume data gathered from scientific fields ranging from biological science to earth science, has given researchers the opportunity to visualise internal structures from new perspectives [Kau90]. Volume visualisation techniques are already common place in medical applications. Research combining volume visualisation and virtual reality with 3D ultraso..

Signal Transition Graph Constraints for Synthesis of Hazard-Free Asynchronous Circuits with Unbounded-Gate Delays

A synthesis procedure for asynchronous control circuits from a high level specification, signal transition graph (STG), is described. In this paper, we propose some syntactic constraints on STG to guarantee hazard-free implementation. We have introduced a global persistency concept in order to establish the relationship between the persistency concept introduced by Chu [2] (which we call local persistency) and the consistent state coding (CSC). The STG syntactic constraints required to compute the input set of a signal are identified. We analyze all hazards under both single and multiple input change conditions and propose necessary changes to the net contraction and logic synthesis procedures. The proposed changes are guaranteed to generate hazard-free circuits with the unbounded-gate delay model, if the STG is live, safe and has consistent state coding. 1 1 Introduction Synthesis of asynchronous circuits is gaining popularity due to inherent clock distribution and clock skew prob..