In order to assess the value of haemodynamic monitoring in the coronary care unit for long term prognosis after recovery of an acute myocardial infarction, the records of two groups of consecutive patients were reviewed retrospectively. From 254 patients, 32 (13%) died in the hospital and nine patients had to be excluded from subsequent follow-up for various reasons. Four year mortality among the 213 patients who were discharged from the hospital and could be followed up was 26%. Of the haemodynamic variables measured on admission a high pulmonary capillary wedge pressure, exceeding 18 mmHg, and a low mixed venous oxygen saturation, less than 60%, were not only associated with a high hospital but also with a high four year mortality, whereas a low systolic blood pressure (less than 100 mmHg), an important prognosticator during admission to hospital, was only of minor significance thereafter. A negative value on admission of a specific index 0.24 X systolic blood pressure (mmHg) -0.217 X pulmonary capillary wedge pressure (mmHg)+0.234 X mixed venous oxygen saturation (%)-13.1 developed for the prediction of short term survival was also associated with a much higher four year mortality than a positive value. Low cardiac index on admission could be correlated with high mortality during the first two years after discharge, whereas only 9% of patients with a higher cardiac index died. Haemodynamic monitoring in the coronary care unit is thus not only relevant for the immediate prognosis, but a high mortality risk during hospital stay persists for several years after discharge.