13th International Congress
THE "NEW FRONTIERS"
OF ARRHYTHMIAS 1998

January 24-31, 1998
Marilleva, Trento, Italy

S-4

Implantable atrial defibrillator with ventricular back-up

Werner Jung, Christian Wolpert, Susanne Spehl, Bahman Esmailzadeh*, Dirk Tenzer, Burghard Schumacher, Berndt Lüderitz.
Departments of Medicine-Cardiology and * Cardiovascular Surgery, University of Bonn, Bonn, Germany

Introduction

Currently available fourth generation implantable cardioverter defibrillators use a single ventricular electrogram for sensing and detection of tachyarrhythmias. Detection is accomplished by classifying each interval between successive sensed ventricular events as fast or slow according to programmable rate criteria. Some devices offer more than two rate zones. Rate zone counters keep track of progress towards detection. Detection is complete when a zone counter exceeds a programmed limit. It is reported that between 27% and 41% of ventricular tachyarrhythmia detections are inappropriate even with added programmable features such as stability and onset¹.