BackgroundPatients requiring an intra-aortic balloon pump (IABP) after cardiac surgery are critically ill and need a prolonged ICU stay. Considering limited health care resources, the early identification of patients with an extremely poor prognosis is important as a solid base for the decision whether further aggressive continuation or cessation of the therapy is recommendable.MethodsFrom 2001 to 2007, 552 patients with low-output syndrome after open-heart surgery and IABP implantation in OR or within 24 h thereafter on ICU were retrospectively analyzed.ResultsThe overall mortality at 30 and 180-day were 31 and 40 %, respectively. According to multivariate analyses, following factors were used to generate an IABP score: female gender, age ≥70 years, simultaneous coronary and valve surgery, aortic cross-clamp time >120 min., need of norepinephrin more than 0.4 µg kg−1 min−1, postoperative dialysis, and maximal serum creatinine kinase >3000 mg mL−1. The 30-day mortality continuously increased along the score (10.1 % for score = 0, n = 98; 11.8 % for score = 1, n = 144; 27.5 % for score = 2, n = 153; 40.4 % score = 3, n = 89; 65.2 % for score = 4, n = 46; 77.8 % for score = 5, n = 27) and reached 100 % for all patients with a score of 6 (n = 4).ConclusionsPrediction of 30 days mortality was possible with our scoring system based on multivariate analysis, and patients with scores of 4 or greater had remarkably worse early and late survival.