Implantable defibrillators as originally conceived by Michel Mirowski were limited to the detection and automatic termination of ventricular fibrillation. In the original "AID" device, the detection algoritlun sought to distinguish sinus rhytlun from ventricular fibrillation by identifying the "more sinusoidal waveform of ventricular fibrillation. " The therapeutic intervention was elicited only once deadly polymorphic rhythms had developed. It was rapidly learned, however, that ventricular fibrillation is usually preceded by ventricular tachycardia. Mirowski recognized the pivotal importance of developing algoritllms based on heart rate. Ventricular tachycardia detection allowed the successful development of interventions for the termination of ventricular tachyarrhythmias before they degenerated into ventricular fibrillation. Current device therapy no longer confines itself to tlle termination of chaotic rhythms but seeks to prevent them. Diagnostic algorithms moved upward along the chain of events leading to catastrophic rhytlulls. Rate smoothing algorithms were developed to prevent postextrasystolic pauses from triggering ventricular and atrial tachyarrhytlmlias. Beyond the renaissance of ectopy-centered strategies, long-term prevention received increasing attention. Multisite pacing therapies provided by "Arrhythmia Management Devices" were designed to reduce the "arrhytlunia burden" and optimize the synergy of cardiac contraction and relaxation. Clinical evidence now suggests that atrial fibrillation prevention by pacing is feasible and tllat biventricular pacing may be of benefit in selected patients with heart failure. However, these applications of device therapy that generally require ventricular defibrillation backup remain investigational and were not considered in this book.

The past 10 years have seen a remarkable change in the approach to cardiac arrhythmias, from a position of confidence and a feeling of well-being about pharmacological treatment to a situation in which there is now marked uncertainty and general apprehension about the role of antiarrhythmic drugs. Until relatively recently the prevailing concept in antiarrhythmic therapy was that arrhythmias could be controlled by drugs which slowed conduction or suppressed automaticity, goals well served by the sodium channel-blocking drugs and glycosides. Drug re search was based largely on the development of agents mimicking those already available, but with greater efficacy, fewer side effects or a more favourable phar macokinetic profile. The CAST trial stands out as a landmark in the evolution of arrhytmia manage ment; rarely has a single trial had such a profound impact not only on clinical prac tice, but also on the whole approach of those involved in the research, development and regulation of antiarrhythmic drugs. The results of the CAST trial, designed to redress the shortcomings of earlier trials which had failed to demonstrate the anticipated improvement in mortality post-myocardial infarction with the use of class I agents, are well known. The CAST and CAST II showed an increase in mor tality associated with the active agent (encainide, flecainide or morizicine) com pared to placebo treatment. They firmly established the potential danger in the use of class I drugs."

Implantable defibrillators as originally conceived by Michel Mirowski were limited to the detection and automatic termination of ventricular fibrillation. In the original "AID" device, the detection algoritlun sought to distinguish sinus rhytlun from ventricular fibrillation by identifying the "more sinusoidal waveform of ventricular fibrillation. " The therapeutic intervention was elicited only once deadly polymorphic rhythms had developed. It was rapidly learned, however, that ventricular fibrillation is usually preceded by ventricular tachycardia. Mirowski recognized the pivotal importance of developing algoritllms based on heart rate. Ventricular tachycardia detection allowed the successful development of interventions for the termination of ventricular tachyarrhythmias before they degenerated into ventricular fibrillation. Current device therapy no longer confines itself to tlle termination of chaotic rhythms but seeks to prevent them. Diagnostic algorithms moved upward along the chain of events leading to catastrophic rhytlulls. Rate smoothing algorithms were developed to prevent postextrasystolic pauses from triggering ventricular and atrial tachyarrhytlmlias. Beyond the renaissance of ectopy-centered strategies, long-term prevention received increasing attention. Multisite pacing therapies provided by "Arrhythmia Management Devices" were designed to reduce the "arrhytlunia burden" and optimize the synergy of cardiac contraction and relaxation. Clinical evidence now suggests that atrial fibrillation prevention by pacing is feasible and tllat biventricular pacing may be of benefit in selected patients with heart failure. However, these applications of device therapy that generally require ventricular defibrillation backup remain investigational and were not considered in this book.

Dieses Buch beschreibt die experimentellen Grundlagen und die ersten klinischen Erfahrungen mit der Anwendung der Hochfrequenzablation bei Patienten mit tachykarden Herzrhythmusstorungen. Es stellt auch neue Kriterien zur Lokalisationsdiagnostik akzessorischer Leitungsbahnen sowie von Kammertachykardien dar. Diese zusammenfassende Darstellung in deutscher Sprache legt einen Grundstein fur Elektrophysiologen und Kardiologen, die an der nichtmedikamentosen Behandlung von tachykarden Herzrhythmusstorungen interessiert sind - einem Therapieverfahren, das in den letzten Jahren zunehmend an Bedeutung gewonnen hat. Sie bietet jedem Arzt, der Herzrhythmusstorungen behandelt, fundierte Information uber diese neue Therapietechnik.