Mobile equivalent heart generator (migrating dipole).

The study is concerned with quantitative mapping of electrocardiographic potentials on the human body surface at various applications of equivalent multipole heart generators. The accuracy or reproduction of the electrical heart field with the application of mobile and immobile dipole and quadrupole generators is compared. The immobile equivalent generator (EG) is fixed in the geometrical centre of the trunk, whereas the mobile EG follows the path of the electrical heart centre during the heart cycle. Four healthy subjects and two patients with permanent postmyocardial ECG changes were examined. On transition from the immobile to the mobile model, in both groups of probands the relative contribution of the quadrupole component to the total potential of the body surface steeply diminished, with consequent substantial increase in accuracy of the dipole heart description. The dipole following the path of the electric heart centre during the heart cycle represents one of the most promising models, and deserves attentive clinical testing.