Induced Atrial Flutter in Rabbit Hearts Tissue and Inverse Magnetocardiography

Abstract

The possibility of non-invasive magnetic identification of electrical tissue activation during atrial flutter in humans is of great clinical interest. Most of the known evidence through electrical [1,2,3] and magnetic [4,5] measurements suggests the existence of a circular motion of the electrical activation (reentry) pattern as the underlying mechanism of this arrhythmia. A new animal experimentation protocol has been developed here in order to allow controlled studies of the reentiy circuit in isolated pieces of rabbit atrium during experimentally induced flutter arrhythmia. In this preparation, the size of the tissue, its anatomical characteristics and the distance from the plane of the sample to the magnetic sensor can be taken into account. The underlying basis for the present work is the “equivalent circular dipole model” presented elsewhere [4]. Therefore, both the animal experimentation and signal processing protocols were based on the rotationally invariable structure of this model. Such stnicture led to good results, overcoming experimental difficulties due to small number of measurement positions and low sensor sensitivity.