European Journal of Cardio-Thoracic Surgery, Vol 11, 1097-1103, Copyright © 1997 by European Association for Cardio-thoracic Surgery
Evaluation of preoperative intra-aortic balloon pump support in high risk coronary patients
JT Christenson, F Simonet, P Badel and M Schmuziger
Cardiovascular Surgery, Columbia Hopital de la Tour, Meyrin-Geneva, Switzerland.
OBJECTIVE: The intra-aortic balloon pump (IABP) is an established
additional support to pharmacological treatment of the failing heart after
myocardial infarction, unstable angina and cardiac surgery. The effect of
preoperative IABP in high risk patients was evaluated. METHODS: Between
June 1994 and March 1996 all high risk patients for CABG (two or more of
these criteria: Left ventricular ejection fraction (LVEF) < or = 40%,
left main stem stenosis > or = 70%, REDO-CABG, unstable angina) were
randomized into either of 3 groups: (1) IABP 1 day prior to surgery, (2)
IABP 1-2 h prior to CPB and (3) no preoperative IABP, controls. Exclusion
criteria: cardiogenic shock preoperatively. Fifty-two patients have entered
the study-group 1 (13 patients), group 2 (19 patients) and group 3 (20
patients). Preoperative patient characteristics and operative data revealed
no group differences. There were 56% REDO's, unstable angina 59%, LVEF <
or = 40%, 87% (34.0 +/- 11.6%) and left main stem stenosis in 35%. RESULTS:
The CPB-time was shorter in groups 1 and 2 88.7 +/- 20.3 min than in group
3 105.5 +/- 26.8 min, P < 0.001, while ischemia time did not differ.
Hospital mortality was higher in group 3, 25% vs. 6% (groups 1 and 2).
Postoperative low cardiac output was seen in 12 patients (60%) in group 3
vs. 6 patients (19%) in groups 1 and 2, P < 0.05. Cardiac index
increased significantly prior to CPB in groups 1 and 2. After CPB cardiac
index was significantly higher in groups 1 and 2 compared to Group 3 and
continued to increase. The IABP was removed after 3.1 +/- 1.0 days in group
3 vs. 1.3 +/- 0.6 days in groups 1 and 2, P < 0.001. In group 3, 11
patients required IABP postoperatively compared to only 4 patients in
groups 1 and 2. ICU stay was shorter in groups 1 and 2--2.3 +/- 0.9 days
vs. 3.5 +/- 1.1 days for group 3, P = 0.004. All patients received dopamin
postoperatively, however in a lower dose in groups 1 and 2, 4.5 vs. 13.5
microg/kg/min. Dobutamine was added in 23% of the patients (group 1), 32%
(group 2) and 95% (group 3). Adrenalin/amrinonum was required in 40% of the
patients in group 3, 5% in group 2 and none in group 1. Group 1 patients
had a better improvement of cardiac performance than group 2, while other
parameters did not differ. Three months follow up of hospital survivors
showed no group differences. CONCLUSIONS: The use of preoperative IABP in
high risk patients lowers hospital mortality and shortens the stay in ICU,
due to improved cardiac performance, compared to a controls. The procedure
was cost-beneficial. One day preoperative IABP treatment improves cardiac
performance more than 1-2 h preoperative IABP treatment, but does not
significantly affect the outcome in terms of hospital mortality or
postoperative morbidity.