[Mathematical model of the kinetics of radiopharmaceutical preparations in the right compartments of the heart].

The paper is concerned with the description of a mathematical model of the kinetics of radiopharmaceutical drugs (RPD) in the right heart with due regard for its two-compartmental structure. A formula has been obtained to describe a right heart radiogram (RHRG) for any RPD entry into the heart (with any type of entry function). It has been shown that in case of an impulsed entry a RHRG curve is described by the following formula (formula; see text) which is a biexponential one. The above formula shows that the determination of phi 1 and phi 2 factor on a curve gives an opportunity to obtain exact information on the correlation of cardiac chamber volumes (the auricle and ventricle). The authors point a possibility of using a RHRG curve for the determination of cardiac output and rate. The formulas obtained are of particular value for analysis of the curves of radiocardiography with 133Xe.