Circulating blood volume and its distribution in the heart, lung and body in normal subjects and cardiac patients determined by analog simulation of radiocardiogram.

Abstract

The cardiac index and the circulating blood volume and its distribution in the heart, lung and body were determined by analog computer analysis of the radiocardiogram in thirty four normal subjects and 135 patients with cardiac and pulmonary disorders. Among the 135 patients, thirty four had congestive heart failure and thirteen patients were re-examined after the amelioration of the congestive heart failure. 2. Among the normal subjects, the mean value of the circulating blood volume was 2496 ml/m2, of which 10.8% (268 ml/m2), 10.9%, (272 ml/m2) and, 78.3%(1955 ml/m2) were distributed in the heart, lung and body, respectively. 3. In patients with valvular diseases, the circulating blood volume and the heart volume increased in accordance with the severity of the disease. The increase in the pulmonary blood volume was also evident in most of the groups but the extent of the incerase was by far smaller than that of the heart volume. The increase of the volume of blood in the body was insignificant in most of the groups. The heart volume was shown to have an important role in terms of the increase in the circulating blood volume. 4. Thirty four patients with congestive heart failure were classified into three groups according to the radiocardiographic data. Among the patients in Group A, there was an increase in the volume of blood in the body; in Group B, there was an increase in the volume of blood in the heart and a decrease in the cardiac index; and in Group C, although the change in the distribution of the blood volume was insignificant, the decrease in the cardiac index was remarkably high. This classification was convenient because it corresponded to observable clinical features, that is, those in Group A had right heart failure, those in Group B had congestive heart failure caused by valvular diseases-mainly by mitral valvular lesions, and those in Group C had heart failures caused by hypertensive and myocardial diseases. 5. After the amelioration of the congestive heart failure, the decrease in the volume of body blood was shown in most patients in the Groups A and B. A slight increase in the cardiac index was the only notable change in Group C.