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

Background. Beneficial effects of preoperative intraaortic balloon pump (IA BP) 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 far preoperative IABP supp ort in a cohort of high-risk patients. Methods. Sixty consecutive high-risk patients who had coronary artery bypas s grafting (presenting with two or more of the following criteria: left ven tricular ejection fraction less than 0.30, unstable angina, reoperation, or left main stenosis greater than 70%) entered the study. Thirty patients di d not receive preoperative IABP (controls), 30 patients had preoperative IA BP therapy starting 2 hours (T2), 12 hours (T12), or 24 hours (T24), by ran dom 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 o ne death in the IABP group and six in the control group. The complication r ate for IABP was 8.3% (n = 5) without group differences. Cardiac index was significantly higher postoperatively (p < 0.001) in patients with preoperat ive IABP treatment compared with controls. There were no significant differ ences between the three IABP subgroups at any time. The incidence of postop erative 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 = 0.00 2, respectively). There were no differences between the IABP subgroups in a ny of the studied variables. Conclusions. The beneficial effect of preoperative IABP in high-risk patien ts who have coronary artery bypass grafting was confirmed. There were no di fferences in outcome between the subgroups; therefore, at 2 hours preoperat ively, IABF therapy tan be started. (Ann Thorac Surg 1999;68:934-9) (C) 199 9 by The Society of Thoracic Surgeons.