Effects of intraaortic balloon pumping on acute myocardial infarction in 64 cases of cardiogenic shock, severe heart failure and mechanical heart failure.

Of the patients treated in the CCU of Nippon Medical School for acute myocardial infarction in the past 5 years and 8 months, 44 with cardiogenic shock, 11 with severe heart failure, 7 with ventricular septal perforation and 2 with mitral regurgitation were treated by IABP. The peak effect of IABP on the hemodynamics of patients with cardiogenic shock was noted 24 hours after starting on IABP. When hemodynamics were compared between surviving and dead groups, there was a significant difference in stroke volume index between the two groups. When left ventricular function was compared between them, it was suggested that patients whose left ventricular function does not respond to IABP for 48 hours or longer are more likely to die than responders. Twenty-four of 44 patients became independent of IABP, but no more than 13 patients (30%) survived for 6 months or longer. Isosorbide dinitrate (ISDN) was combined with IABP in 7 patients who had a persistence of heart failure in spite of IABP. Combination therapy with IABP and ISDN elicited a significant increase in cardiac index, a significant decrease in pulmonary capillary wedge pressure, mean pulmonary arterial pressure and total peripheral resistance and a pronounced improvement in left ventricular function, and all 7 patients became independent of IABP. In the patients with acute myocardial infarction complicated with ventricular septal perforation, the mean systolic arterial pressure was 87.7 +/- 8.3 mmHg, mean pulmonary capillary wedge pressure, 20.3 +/- 7.4 mmHg and pulmonary-to-systemic flow ratio, 3.12 +/- 0.95 before starting on IABP. When the hemodynamics at 3 hours of IABP were compared to the pre-IABP values, the right atrial pressure, pulmonary capillary wedge pressure and pulmonary-to-systemic flow ratio had a tendency to decline, but the changes were not statistically significant, except for the peak arterial pressure which showed a significant elevation at 3 hours of IABP. Three of the 7 patients became dependent on IABP, and 2 of the 3 patients were saved by emergency operation.