The survival of subjects with postmyocardial infarction cardiogenic shock treated with intra-aortic balloon pumping (IABP) differs significantly among various reports. Differences in the criteria for IABP application and in the timing of its initiation have been considered as the main reasons for variations in survival. This study examines whether the way patients in cardiogenic shock are treated prior to IABP may affect their survival. Fifty-five patients in severe postmyocardial infarction cardiogenic shock were classified into three groups according to the rate of dobutamine infusion prior to IABP: the "nondobutamine" (group A, n = 31), the "high-dose dobutamine" (8 to 20 micrograms.kg-1.min-1, group B, n = 17), and the "low-dose dobutamine" (up to 7 micrograms.kg-1.min-1, group C, n = 7). All subjects seen from 1978 to 1983 were recruited for group A, from 1986 to 1990 for group B, and in years 1984, 1985, and 1991 for group C, without using any other classification criteria. It was shown a posteriori that the three groups did not differ in the features of the subjects, in the severity of shock, and in the time length between onset of shock and pumping initiation. None of the 17 subjects of group B could survive under pumping, while 10 of the 31 subjects in group A and 4 of the 7 subjects in group C were weaned off pumping.
Conclusions: A protracted, high-dose pre-IABP administration of dobutamine may adversely affect the survival of patients with postmyocardial infarction cardiogenic shock.