Spatial- temporal characteristics of the electric field of atria in rats with experimentally induced pulmonary hypertension

Pulmonary hypertension connected with an increase of arterial pressure contributes to the development of hypertrophy of the right heart. An increase of the absolute weight and relative mass of the heart is revealed in rats with monocrotaline (MCT)-induced pulmonary hypertension. An increase of duration of atrial depolarization, being steady during ascending and descending phases of the P- wave, and earlier formation of the cardiac electric field typical for the initial atrial activity have been shown in rats with MCT-induced pulmonary hypertension by using a method of multichannel synchronous electrocardiotopography. After injection of the preparation changes in the location of areas of positive and negative cardioelectric potentials on the body surface have been revealed during all the periods of atrial depolarization: before the beginning of the P- wave and during ascending and descending phases of the P-wave on the ECG that testifies to the changes in the sequence of atrial depolarization.