Risk factors and outcome in European cardiac surgery: analysis of the EuroSCORE multinational database of 19030 patients

Objective: To assess risk factors for mortality in cardiac surgical adult p atients as part of a study to develop a European System for Cardiac Operati ve Risk Evaluation (EuroSCORE). Methods: From September to November 1995, i nformation on risk factors and mortality was collected for 19030 consecutiv e adult patients undergoing cardiac surgery under cardiopulmonary bypass in 128 surgical centres in eight European states. Data were collected for 68 preoperative and 29 operative risk factors proven or believed to influence hospital mortality. The relationship between risk factors and outcome was a ssessed by univariate and logistic regression analysis. Results: Mean age ( +/- standard deviation) was 62.5 +/- 10.7 (range 17-94 years) and 28% were female. Mean body mass index was 26.3 +/- 3.9. The incidence of common risk factors was as follows: hypertension 43.6%, diabetes 16.7%, extracardiac a rteriopathy 2.9%, chronic renal failure 3.5%, chronic pulmonary disease 3.9 %, previous cardiac surgery 7.3% and impaired left ventricular function 31. 4%. Isolated coronary surgery accounted for 63.6% of all procedures, and 29 .8% of patients had valve operations. Overall hospital mortality was 4.8%. Coronary surgery mortality was 3.4% In the absence of any identifiable risk factors, mortality was 0.4% for coronary surgery, 1% for mitral valve surg ery, 1.1% for aortic valve surgery and 0% for atrial septal defect repair. The following risk factors were associated with increased mortality: age (P = 0.001), female gender (P = 0.001), serum creatinine (P = 0.001), extraca rdiac arteriopathy (P = 0.001), chronic airway disease (P = 0.006), severe neurological dysfunction (P = 0.001), previous cardiac surgery (P = 0.001), recent myocardial infarction (P = 0.001), left ventricular ejection fracti on (P = 0.001), chronic congestive cardiac failure (P = 0.001), pulmonary h ypertension (P = 0.001), active endocarditis (P = 0.001), unstable angina ( P = 0.001), procedure urgency (P = 0.001), critical preoperative condition (P = 0.001) ventricular septal rupture (P = 0.002), noncoronary surgery (P = 0.001), thoracic aortic surgery (P = 0.001). Conclusion: A number of risk factors contribute to cardiac surgical mortality in Europe. This informati on can be used to develop a risk stratification system for the prediction o f hospital mortality and the assessment of quality of care. (C) 1999 Elsevi er Science B.V. All rights reserved.