MAJOR DETERMINANTS OF SURVIVAL AND NONSURVIVAL OF INTRAAORTIC BALLOON PUMPING

The purpose of this study was to find the major determinants of survival and nonsurvival after intraaortic balloon pump (IABP) support. One hundred twenty-nine consecutive patients with IABP support from January 1988 to January 1992 were analyzed retrospectively. Differences between the survival and nonsurvival groups were tested with the Student's t test, chi-squared test, and frequency analysis. The overall survival rate was 50.4% (65 of 129). Nonsurvivors (64 of 129, 49.6%) had higher rates of chronic heart failure (21.9% vs 9.2%, p < 0.05), acute myocardial infarction (53.1% vs 24.6%, p < 0.01), cardiomyopathy (9.4% vs 1.5%, p < 0.05), New York Heart Association functional class IV (51.6% vs 13.9%, p < 0.01), and depressed left ventricular ejection fraction (29.38% +/- 8.99% vs 42.88% +/- 5.24%, mean +/- SD, p < 0.01). The nonsurvival group also had longer duration of cardiopulmonary bypass (115.80 +/- 24.43 vs 78.34 +/- 3.81 min, mean +/- SEM, p < 0.02) and aortic occlusion (57.55 +/- 13.03 vs 41.00 +/- 2.79 min, mean +/- SEM, p < 0.05) than the survival group. The major determinants of death after IABP are acute myocardial infarction, left ventricular ejection fraction < 30%, New York Heart Association functional class IV, and longer duration of cardiopulmonary bypass and aortic occlusion. IABP is effective in sustaining hemodynamics, but severe myocardial pump failure portends a poor treatment outcome.