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

January 24-31, 1998
Marilleva, Trento, Italy

S-113

Inappropriate ICD therapies-incidence, causes and prevention by programming stability and onset criteria

Max Weber, Martin Borggrefe, Günter Breithardt, Michael Block.
Department of Cardiology and Angiology, Institute for Arteriosclerosis Research, Hospital of the Westfälische Wilhelms-University, Münster, Germany

Introduction

Inappropriate therapies defined as shocks or antitachycardia pacing for rhythms other than ventricular tachycardia (VT) or ventricular fibrillation, are the most common adverse events in patients with an implantable cardioverter defibrillator (ICD). Discrimination between slow VT and supraventricular tachyarrhythmias is particularly difficult, causing many inappropriate ICD therapies^1-6. Pain due to inappropriate shocks might limit the patients acceptance of the ICD and even can cause psychic disorders⁷. Inappropriate therapies might induce dangerous or even fatal ventricular arrhythmias, can cause battery depletion or lead to the exhaustion of all possible ICD therapies^8,9.

Multiple enhanced detection criteria are offered to discriminate these supraventricular tachyarrhythmias from slow VT. Most widely used are the stability criterion to differentiate VT from atrial fibrillation and the onset criterion to distinguish VT from sinus tachycardia.