Abstract
The modern treatment of cancer is a group project, requiring the close cooperation of the surgeon, the radiologist and the internist. Among the more important problems with which the internist must deal are the effects of radiant energy on vital structures, such as the gastrointestinal system, the kidneys, the lungs and the heart, in patients who are receiving or have received radiation therapy. The purpose of this paper is to report these effects on the cardiovascular system as they have been observed clinically. This paper is the fourth in a series from the medical service of Memorial Hospital on the effect of radiation therapy on the heart and the lungs. The first two1 dealt with the immediate and the late effects of high voltage roentgen rays on the hearts of adult rats. Work now in progress will supplement these reports and is concerned with the pathologic physiology of chronic