Short-term survival after acute myocardial infarction predicted by hemodynamic parameters.

Abstract

In the acute phase of myocardial infarction, short-term prediction of the likelihood of survival helps the physician choose the appropriate therapy for individual patients. Of 122 patients admitted to the coronary care unit of the Thoraxcenter, University Hospital, Rotterdam, with an acute myocardial infarction, 16 died from pump failure. In these and the 106 survivors, the predictive value of peripheral systolic (SP) and diastolic (DP) blood pressure, pulmonary capillary wedge pressure (PCW), mixed venous oxygen saturation (MVO2sat) in the pulmonary artery and heart rate (HR), both alone and in combination, was evaluated at the time of admission and 24 hours later. When, at admission, (DP X MVO2sat)/PCW exceeded 250%, 97/99 patients survived, whereas values below 250% were associated with death in 14/23. All other papameters, taken alone or in other combinations, showed less discriminatory power. Thb mean value of this index in survivors (549%) was statistically different (P less than 0.001) from the mean value in nonsurvivors (183%). Twenty-four hours later all survivors with admission values lower than 250% had an improved index. Of the 14 nonsurvivors with admission values lower than 250%, seven had already died, and in seven others the index had decreased still further; Linear discriminant analysis showed that (0.024 SP -- 0.217 PCW + 0.234 MVO2sat) was the most powerful prognostic index at the time of admission; its time course did not provide a more effective prediction of ultimate fatality than (DP XMVO2sat)/PCW. Determination of (DP X MVO2sat)/PCW in patients hospitalized for acute myocardial infarction provides a reliable prognosis for short-term patient survival. Its practical value in guiding patient management, more particularly for initiating mechanical circulatory assistance or for emergency surgery, must be further assessed.