Two pumps and one heart: studies and theoretic considerations.

Using 2 pumps specially constructed to simulate the right and left ventricles of the heart of man, it was shown that very small differences in output per stroke of the 2 pumps will result in a significant change in the volume of the "pulmonary" circulatory system and could become "pathophysiologically" important with time. These studies demonstrate that both ventricles must be well synchronized and regulated to maintain good health and to prevent dyspnea and other manifestations of CHF. They also indicate the inadequacy of the conventional methods used for measuring cardiac output in man and the need to measure stroke volume or cardiac output of both ventricles separately and simultaneously. It must not be assumed that the cardiac output is always equal for both ventricles even in the presence of myocardial disease. An explanation is introduced for the acute onset of dyspnea associated with angina pectoris and with exercise. Also, the concept that the ventricles fill, at least in part, by "sucking" action is presented, with support from these and other theoretic considerations.