Mortality in patients supported by intra-aortic balloon pump in the course of cardiac surgery was related to perioperative myocardial infarction

Objective. To search for predictors of mortality for patients in need of intra-aortic balloon pump (LABP) support in the course of cardiac surgery. Methods. A retrospective study of possible pre- and perioperative risk factors in 110 patients with mean age of 62 years (35-79). The IABP was inserted preoperatively in 19 (17%) and preoperatively in 91 (83%). Results. Well known risk factors as advanced age (63.2/61.0; P = 0.25), NYHA functional class (OR = 1.59; 95% CI 0.23 to 13.31), female sex (OR = 2.40; 95% CI 0.81 to 6.73), emergency surgery (OR = 0.63; 95% CI 0.21 to 1.80), low left ventricular ejection fraction (62.9/60.7; P = 0.53), or elevated end diastolic pressure (19.4/21.0; P = 0.48), were not prognostic of death, Perioperative insertion of the balloon pump (OR = 3.83; 95% CI 1.07 to 14.95), perioperative myocardial infarction (OR = 23.3; 95% CI 7.62 to 81.8), low cardiac output (OR = 7.53; 95% CI 2.43 to 24.11), and renal failure (OR = 20.00; 95% CI 3.63 to 145), were strong predictors of death. Conclusions. Outcome seemed to be determined by perioperative events rather than preoperative risk factors. This could possibly explain the favourable mortality rates seen in patients on IABP support prior to surgery compared to patients who had IABP installed perioperatively.