Investigations on left ventricular function in patients with acute myocardial infarction and the relatonship to clinical findings have shown: (1) limitations in the use and interpretation of central venous pressure; (2) pulmonary artery end-diastolic pressure accurately reflects left ventricular filling pressure in the absence of pulmonary vascular or mitral valve disease; (3) left ventricular filling pressure is frequently elevated in mild or clinical uncomplicated infarction; (4) left ventricular function frequently improves during the immediate as well as late convalescent period; (5) the hemodynamic and clinical evaluations may frequently be at variance; (6) a left ventricular gallop is usually associated with an abnormally elevated left ventricular filling pressure; (7) anterior infarctions present greater depression of left ventricular function than inferior infarctions; and (8) monitoring of hemodynamics can be useful in following the changes in left ventricular function and the response to therapy in patients with heart failure and cardiogenic shock.