Optimal timing of preoperative intraaortic balloon pump support in high-risk coronary patients.

Background: Beneficial effects of preoperative intraaortic balloon pump (IABP) treatment, on outcome and cost, in high-risk patients who have coronary artery bypass grafting have been demonstrated. We conducted a prospective, randomized study to determine the optimal timing for preoperative IABP support in a cohort of high-risk patients.

Methods: Sixty consecutive high-risk patients who had coronary artery bypass grafting (presenting with two or more of the following criteria: left ventricular ejection fraction less than 0.30, unstable angina, reoperation, or left main stenosis greater than 70%) entered the study. Thirty patients did not receive preoperative IABP (controls), 30 patients had preoperative IABP therapy starting 2 hours (T2), 12 hours (T12), or 24 hours (T24), by random assignment, before the operation. Fifty patients had preoperative left ventricular ejection fraction mean, less than 0.30 (less than 0.26+/-0.08), (n = 40) unstable angina, 28% (n = 17) left main stenosis, and 32% (n = 19) were reoperations.

Results: Cardiopulmonary bypass was shorter in the IABP groups. There was one death in the IABP group and six in the control group. The complication rate for IABP was 8.3% (n = 5) without group differences. Cardiac index was significantly higher postoperatively (p<0.001) in patients with preoperative IABP treatment compared with controls. There were no significant differences between the three IABP subgroups at any time. The incidence of postoperative low cardiac output was significantly lower in the IABP groups (p<0.001). Intubation time, length of stay in the intensive care unit and the hospital was shorter in the IABP groups (p = 0.211, p<0.001, and p = 0.002, respectively). There were no differences between the IABP subgroups in any of the studied variables.

Conclusions: The beneficial effect of preoperative IABP in high-risk patients who have coronary artery bypass grafting was confirmed. There were no differences in outcome between the subgroups; therefore, at 2 hours preoperatively, IABP therapy can be started.