We assessed the prognostic value of cardiothoracic ratio and plain film heart volume in relation to other clinical, exercise, hemodynamic and quantitative angiographic variables. Both cardiothoracic ratio and plain film heart volume are highly sensitive, but nonspecific, indicators of abnormal left ventricular end-diastolic volume and ejection fraction. Both variables are univariately important predictors of survival in cohorts of medically and surgically treated heart disease patients. Plain film heart volume significantly adds to the multivariate prediction of prognosis obtained from groups of clinical, exercise, hemodynamic and quantitative angiographic variables. These measurements from the routine chest roentgenogram are sensitive detectors of abnormal left ventricular function or volume and important predictors of long-term survival. The fact that they contribute prognostic information in addition to left ventricular volume and ejection fraction suggests that other cardiac chamber volumes are of prognostic importance.