The evaluation of left ventricular function in patients with acute myocardial infarction has shown: 1. Limitations in the use and interpretation of central venous pressure. 2. Pulmonary artery end-diastolic pressure reflects left ventricular end-diastolic pressure in the absence of pulmonary vascular or mitral valve disease. 3. Frequent elevations of left ventricular filling pressure in mild or clinically uncomplicated infarction. 4. Anterior infarctions present greater depression of left ventricular function than inferior infarctions. 5. Initial hemodynamic measurements in cardiogenic shock can predict prognosis with medical management. 6. Left ventricular function frequently improves during the early convalescent period. 7. Hemodynamic monitoring can be useful in following changes in left ventricular function and the response to therapy. The assessment of left ventricular performance in patients with chronic heart disease has shown: 1. Resting hemodynamic measurements are often normal but abnormalities can be observed in patients with disease of the left anterior descending coronary artery, diffuse coronary involvement, and after myocardial infarction. 2. Increases in end-diastolic volume or dilatation and left ventricular mass or hypertrophy can develop in severe coronary disease and after myocardial infarction. 3. The size of abnormally contracting segment after myocardial infarction is related to abnormalities in compliance, ventricular end-diastolic pressure, end-diastolic volume, and clinical manifestations of heart failure. 4. Exercise and atrial pacing can produce clinical and hemodynamic abnormalities. 5. The ejection fraction is significantly related to the slope of the ventricular function curve. 6. Angiographic abnormalities of left ventricular wall motion can be increased with atrial pacing and reduced with nitroglycerin or epinephrine.