The formation of the cardioelectric field on the fish body surface during atrial depolarization

The reflection of sequence of atrial depolarization of the epicardium on the fish body surface has been studied for the first time (Atlantic cod Gadus morchua ). The formation of cardioelectric potentials on the body surface of fish is revealed at initial stages of atrial depolarization before the beginning of the P-wave in the ECG in the bipolar leads. The propagation of the excitation wave along the fish atrium from the venous sinus to the atrioventricular orifice is reflected in the change of the spatial location of areas of positive and negative cardioelectric potentials and displacement of extrema of the cardioelectric field on the body surface.