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

January 24-31, 1998
Marilleva, Trento, Italy

RT-247

A method to evaluate contemporary refractoriness and conduction velocity at different atrial sites during human atrial fibrillation

Antonio Michelucci, Luciano Alcidi*, Silvio Vena, Luigi Padeletti, Maria Cristina Porciani, Pasquale Imperiale*, Andrea Colella, Salvatore Romano*, Gian Franco Gensini.
Istituto di Clinica Medica Generale e Cardiologia, * Dipartimento di Fisiopatologia Clinica, Universita di Firenze, Italy

Introduction

Evaluation of refractoriness during atrial fibrillation in man has been performed analysing interval between atrial electrograms^1-3. Instead scarce data⁴ have been reported concerning the behaviour of local conduction velocity. Evaluation of the latter could be done accepting that the duration of the atrial potential is proportional to the time necessary to atrial impulse to pass over the recording bipolar electrodes. On this basis we can assume, for example, that if the potential is larger, then the time of atrial impulse is longer and its velocity is slower; thus we can consider that the conduction velocity correlated inversely with the width of intra-atrial potentials.

On this basis we undertook a computerized analysis of the intra-atrial potentials durig atrial fibrillation in the electrophysiologic study to evaluate contemporaneously and dynamically: 1) the interval between intra-atrial potentials (f-f interval: as expression of local refractoriness); 2) the width of the intra-atrial potential (f-width: inversely correlated with local conduction velocity).